Web Analytics RiceHigh's Pentax Blog: 2006

Tuesday, December 26, 2006

Reports of Non-Working K10D Internal Flash Continue

Further to my last two reports on this problem with the K10D:-


Here is yet again a thread in which two K10D users write the same:-


I *hope* Pentax could seriously look into the problem and take necessary remedial action promptly, e.g., product recall, revise the design, improve quality control, and/or etc., whatever is/are applicable and appropriate.

Well, I was the very first one to bet that this is not an isolated case but of course many brand loyalists disagreed, just see my first report one month ago:-


Anyway, now that this problem has been widely regarded as a commonly known problem for quite some K10D units.

Saturday, December 23, 2006

Just for Some Funs - HOTAX!

Further to the recent news of Hoya Swallows Pentax, it is revealed that there has been clue quite some times ago and a new camera manufacturing company named "Hotax" ( not "Hoax"! pls beware of the spelling! ;-D ) was found silently and secretly! ;-)

A quick glance at the company's profile will give you an idea how bright the future (and now actually) the HOTAX will be / is:-

"Hotax Manufacturing Company Ltd is a factory to produce various ranges of cameras and monthly capacity is 500,000 pcs. The operations are carried out in the owned factories in Shenzhen (of China)."

Well, the current production capacity and demand of the HOTAX cameras, of *just* for *one month*, is in the amount of 500,000 units, which is the double of the total number of Pentax DSLRs sold in (the late) *one year*, at only 250,000 units for one year! So, it can be regarded that the new company is far more successful than what Pentax have ever achieved and managed/been able to achieve!

Nonetheless, I *had* my very early foresight and grew together with HOTAX back to early last year in 2005, when I got one of the excellent HOTAX waterproof cameras to complement my PENTAX *ist D when I had a vacation trip to the Eastern Australia. Here are a few of the photos from the trip:-


Enjoy! LOL! =^o^=

Friday, December 22, 2006

Season's Greetings!

The Christmas is coming very near! After "nitpicking" and "bashing" (for what certain Pentaxians always say (about me).. ;-)) for nearly one month, since this Blog was started, this time I just wish to convey all the best wishes for the Season's Greetings to all of you folks here!

Wish you all a Very Merry Christmas and a Prosperous and Very Happy New Year of 2007! And, most importantly, wish you happy Pentax shooting and always get great results!!

( Picture Info: K100D + DA 16-45mm @ 16mm; 1/45s, f/4 @ ISO 400 @ IFC Shopping Mall, Hong Kong )

Thursday, December 21, 2006


The shocking news pop up today, HOYA is TO MERGE PENTAX very soon! See the Hoya Press Release below (officially translated in English):-


Here are some facts, quoted from the Press Release above:-

1. The "Merging Company" is HOYA and the "Company to be Merged" is PENTAX;

2. The "Merger of the Two Companies" is expected to be completed by October 1, 2007;

3. "HOYA will be the surviving company", which means that PENTAX is the company which will not survive after the Merger;

4. New Merged Company will be called "HOYA PENTAX HD Corporation", that is, something similar to Konica Minolta when Konica bought Minolta and formed the KM company;

5. Current President & CEO of Pentax Corporation, Fumio Urano, will be downgraded to the Chairman of the Board of Directors and current President & CEO of Hoya Corporation will remain as the President & CEO of the new Merged Company;

6. "Each shareholder of PENTAX common stock will be allotted 0.158 shares of HOYA common stock per PENTAX share", which means that there will be no more PENTAX share/stock as substituted;

Actually, Pentax has also made her own annoucement at Pentax's Japanese website and here is the Press Release (in Japanese):- http://www.pentax.co.jp/japan/news/announce/20061221-02.pdf

To me, this is really a true bad news, as it is fully agreed that Pentax will be "eaten" and "swallowed" very soon by Hoya and the historical old company, Pentax / Asahi, will no longer exist very soon. This would formally mark a full stop for the Asahi Optical Co Ltd, which had its name changed to "Pentax Corporation" just a few years ago.

As an long-time Pentax end-user and a supporter of the company, I found that their optics are far superior to those of Hoya's even just for the protective filters - glass, coatings, workmanship made by Pentax are all far better than those Hoya's offerings, although Hoya's are cheaper. So, I am really upset to see this has happened.

But, anyway, that's the *reality*, no matter anyone feels sad or not.

Update (Dec. 22):
Reuters also have this news reported on the ZDNet, the article link is as follows:-


Below are a few key quotes from the Reuters' report:-

"Hoya, a Japanese maker of optical glass, plans to buy Pentax for about 91 billion yen ($770 million) in shares" - quite a large figure for the capital amount;

"It will be one of the biggest deals in Japan's precision equipment industry since a merger between Konica and Minolta in 2003";

""The most attractive part about Pentax was its medical business," Hoya's Suzuki said during a press conference", which implies that HOYA's major / top concern will still be on the medical optics business, but not on (Pentax's) photographic equipment. In fact, neither Hoya nor Pentax's Press Releases have much to mention about the business on cameras and lenses, too.

Whilst the future of "Pentax" is still unknown, let's wait and see if the future is brighter, or just the reverse. What I am sure now is that there will be a lot of *changes*, for "Pentax".

K10D Hyper Program Defeats Auto ISO

Here is a recent report by a K10D user about how the Hyper Program defeats the Auto ISO:-


The user desribes clearly in details about this bug found in his K10D, and actually he has checked and re-checked the problem again (previously I was wrong in the same thread by replying too early that it is "not a bug"! Just because I thought that it could not happen!):-

"I rechecked again. Definately there's a problem in Hyper program. In my eyes it is definately bug in firmware." - by a K10D user.

Regarding the final question he asks at the end of his post, "How do you report problems to Pentax?" I shall tell him that he can always try to email any user feedback to Pentax. However, my prolonged experience with Pentax tells me clearly that they *won't* reply - they simply ignored all my enquiries and reports, no matter how simple I typed my questions and how polite the tone was. In contrast, if marketing related questions were asked, they responsed within just several days! Funny but sad..

The more sad thing is that even Pentax did receive repeated numerous reports of a simple, obvious and undoubtedly annoying problem, like the (in)famous "EV compensation defeats Auto ISO" symptom in all their DSLRs except the K10D, they had never rectified the problem in any firmware update so far nor they could rectify the problem even in all their coming (once) new products throughout a mercyful lengthy period of more than 3 years, i.e., for all DSLRs marketed from Sept 03 (the *ist D) to Nov 06 (until the K10D). This is very unreasonable afterall.

Pentax's stubbornness and insistency for not having a significant (but simple) reported problem got resolved (not even to mention about the speed), is something that I can never understand.

Yesterday, Pentax have updated their firmware for most of their older DSLRs for SDHC support (but this is a second time firmware udpate on the SDHC compatibility issue). However, after downloaded and installed the latest firmware in my K100D myself, I found that the EV Compensation-Auto ISO EVIL is still there. So, this illustrate how Pentax is, as usual and again, being very unhelpful to all of their old customers, especially considering that the K100D is still a currently marketed product and more importantly, they have known the problem for so long but have come up with a solution, already, in the K10D.

Nonetheless, for those who use SDHC cards in your Pentax DSLRs (except the K10D), you can download the latest firmware here:-

Sunday, December 17, 2006

Where are the Pentax DSLRs and Lenses Made?

This is a frequently asked question which appears from time to time.

Actually, the answers are not difficult to find, just search those popular forum databases or go to major “review” sites to have a look at the photos which show the bottom of the DSLRs (but for lenses, pictures showing the product labels, are rare).

Okay, I tell here for the answers again, for this FAQ: Pentax DSLRs are "Assembled in Philippines" and *current* Pentax digital lenses are “Assembled in Vietnam”, as shown on SOME of the product labels.

It is interesting to note about the word "Assembled" used instead of "Made". People often wonder about the actual difference about this. However, I myself cannot figure out what the actual difference is and why a different word needed to be used, in terms of both the meanings of the two words as well as in practical terms.

Nevertheless, the fact is that Pentax do NOT stick a label showing the place of manufacturing for ALL their DSLR or lens products of the SAME model made by them. Depending on the place and the country where Pentax would ship to, they would particularly have a different version of the labels where the place of made will be omitted totally, or, there is even no trade description label on the products at all, e.g., for lenses. In fact, the recession position for accommodating the labels are omitted all together, on those lens barrels, which means that the production line(s) at the Pentax factory must be tailored to cater for those individual differences.

Since quite some times ago when Pentax marketed the *ist D (which were made in Philippines) and the "kit" lens FAJ 18-35 (which were made in Vietnam) in fall 2003, I have never seen any Pentax products sold in China have any labels which tell where they were made. Below is a shot of the base of my K100D, which was bought earlier this year:-

(My K100D)

For quick comparison, you can see the obvious difference for the following picture of the K100D base, which was reviewed by Phil Askey of Dpreview (and supplied by Pentax):-


By comparing the above two images, it is not difficult to see that it is not only the place of manufacturing is missing, actually four other marks including the common CE mark are "deleted" altogether and only blank spaces are left (for the HK-China version). So, can we understand that all the K100D sold in China do not comply with the CE standard? (as long as the labels are the same as the one on my K100D, and, it is very clear that the marks are intentionally removed)

Additionally, below are a number of shots showing the labels of various generations of Pentax products, for what the places of manufacturing were shown in the past, against those newer digital lenses made (in Vietnam) since 2003 and up till now (again, not applicable for products sold at Japan home market, US, UK and EU countries of which the labels DO show the place of made):-

(Optio 330) (BG-10) (MZ-S) (F 17-28 Fisheye Zoom) (DA 16-45/4) (D FA 100/2.8 Macro)

Okay, at this point, some people may again ask me that "what's the fuss about?". Well, I just wish to ask a few questions arouse from this issue, based on the facts I've pointed out above:-

1. Why the place of manufacturing needed to be omitted and "hidden"? What is the rationale/purpose/intention of Pentax of doing so?

2. Why the omission is limited to Pentax products shipped to particular countries and places, e.g., China and Hong Kong (Well, this would include all e-Bay HK gray market Pentax products sold in Europe, etc.)? Whereas countries like Japan, US, UK and EU countries will have the information “disclosed” and printed?

3. Would it be illegal to omit the information? I know that in the local HK laws, there are legal requirements on the trade description of imported goods for showing the correct country of manufacturing/origin and that the country for which a product is made cannot be mis-quoted. Otherwise, it is illegal. The following are two relevant Chapters of the HK laws about the requirements of the trade descriptions for imported goods:-



In addition, do note that China and Hong Kong are World Trade Organisation Members which the Trade Description requirements are in principle in line with all other member countries, i.e., including Japan, US, UK and all EU countries, according to the WTO Paris Convention Signed.

4. Apart from legal concerns, (what) do you think if this act is ethical or not?

Well, I welcome any inputs and comments on any of my above questions, any further *sensible* discussions with reference to some grounds are encouraged!

On the other hand, as a "counter" example (actually, it is something that should be done, IMHO), I notice that all Canon and Nikon goods sold in HK and China have never had this simple and basic trade information omitted. For example, there were 300D that “Made in Taiwan” as well as some others that were “Made in Japan” on the market, sold at the streets at the same time. Indeed, the labels tell the consumers clearly for a basic piece of information that they might concern with. In the end, the market will have all the outcomes determined, e.g., selling prices, demand volume, and so on.

Another relevant example is that Nikon DSLRs (and some cheaper lenses) are mostly “Made in Thailand”, including D200, D100, D80, D70/70s, D50 and D40. Nikon do show clearly “Made in Thailand” on all their labels on their DSLRs, like this:-


But then the *fact* is that those Nikon DSLRs and lenses are selling much much better than Pentax DSLRs and lenses. So, I just wonder what are the concern(s) (by Pentax) here. Why they need to spend extra efforts and costs at the factory to do something which might be illegal, may be considered as inhonest/unethical, but, probably will have no real commercial benefit of any kind at all, in the end!

From the consumer rights' perspective, it is clear that every buyer has the basic rights to know. Also, haven't Pentax ever thought about the lack of this basic and common (all the competitors have this) information on the labels, would actually de-promote their products, in the other way around? E.g., I know someone in China bought a DA 12-24 lens, he told that he felt not so good for seeing there was no product label/printing for such an expensive lens.

Whilst I do agree that product quality, reliability and performance are the final things which should count for a product, I don't think that the basic trade information, especially considering that it would be a common legal requirement, for most of the countries, should be omitted, especially by intention, and selectively, e.g., why China??

Saturday, December 16, 2006

AF Errors/Problems of the K10D

In my last post, I mentioned about the Front Focusing problem of the K10D as reported by different new K10D users over the Net. I originally expected that for anyone with more interests could search the reports by themselves. However, here is yet a comment to my last post for asking the links (of those reports):-

(See the fourth comment)

Well, in view of this, I think a new separate Blog entry containing a few of those links would be convenient and handy for those who are really interested. Here they are (still just a few of those reports):-

1. http://forums.dpreview.com/forums/read.asp?forum=1036&message=21115135

The above user has both the K10D and K100D and found that the FF symptoms are similar for both units. This post is quite useful as pictures are posted in his post. The user also said, "The FF is slight enough with both cameras that apertures smaller than f/4 or so tend to mask it." So, this just implies the FF errors will easily show up for apertures larger than f/4! (provided that the lens attached is fast enough)

2. http://forums.dpreview.com/forums/readflat.asp?forum=1036&thread=21265823

The above case is even worse, repeatable FF problems were found with the (slow) Kit Lens! See the test shot links included in the post.

3. http://forums.dpreview.com/forums/read.asp?forum=1036&message=20995715

4. http://www.pentaxforums.com/forums/pentax-dslr-discussion/1377-k10d-front-focus-body-lens.html

5. http://www.mail-archive.com/pdml@pdml.net/msg362005.html

Well, if you really wish to see more user reports, just do a simple internet search and/or search the posts forum by forum, using their own search function. It will not be so difficult afterall! :-)

Do note that the chief engineer of the K10D development team previously disclosed in an interview with him that the AF accuracy of the K10D is the same level as the K100D. For more read on the implication of AF accuracy on a high pixel count DSLR as well as the quoted part and the source of the interview, you can read back my previous blog entry below:-


Dpreview puts Low Rating on the Image Quality of K10D

Phil Askey' Full Review on the K10D has been out (it is the first time I have seen Phil Askey has completed a Pentax review so "quickly" and I'm surprised! Congrats, Pentax!):-


Just read the conclusion by Phil Askey and it is clear and self-explanatory for the (obvious) problem / shortcoming found. Indeed, the Rating on Image Quality is marked to be *Very Low*.

Actually, I had found something very close to what Phil has just told more than one month ago, when the production K10D was out and people started to post the production sample pics. After I had inspected quite some of those production sample pics at different websites, I had made some short remarks about my disappointment on the image quality of the K10D, at the Steve's Pentax/Samsung DSLR Forum and here is the thread:-


Anyway, since Steve's site administrator/owner accused me of bashing Pentax over time and my above post for such direct opinions (based on some simple evidence) became one of my "criminal evidence" which contributed to my ban at their premises, it looks really funny to me again when the case is recalled and when I point again to those concerned posts. But, now that Phil Askey reinforces my observations and findings!

However, the more interesting thing is that despite Phil Askey is wise enough to observe and find "negative" thing(s) about the K10D (and even more wise enough to post those particular findings by his own discretion and judgement, which is true for any other DSLRs reviewed by him as well), he did put an iron hand on me by banning me, probably also for just stopping my "negativity", because he banned me also at his forums for my simple opinions and posts made (which I was talking about my true experience in all my replies and I know that they can accuse me of breaking their forum rules by their own intrepretations, anyway..).

Last but not least, whilst Phil Askey comments in his new review that the AF system of the K10D is fast and accurate, I strongly recommend that any potential K10D buyers should do more researches of your own before you are decided as there have been consistently numerous reports at major Pentax forums by quite some new K10D users that obvious and significant focusing errors (most reports are about Front Focusing, especially with large aperture primes like the FA50/1.4 etc.), as well as at low light, the AF system becomes rather sluggish and hunts a lot. Well, the (end of the) stories are that many of the reporting users have their new K10D returned (within the return period).

Again and furthermore, Phil Askey have exactly the same view in his review, as mine, that K100D has a (much) better image engine of which this fact I have being reported from time to time over months, since the K10D beta sample photos were out!

Now, can we regard this: P-R-I-M-E = Phil Rated Inferior iMage Engine? ;->

Finally, I would emphasize here again that Image Quality is the (up)most important thing for any camera. Without good image quality, anything else of any auxiliary features and functions will become not so meaningful, then. Nonetheless, I just wonder why Phil Askey could *still* put a "Highly Recommended" overall rating for the K10D, despite that he tried to add a "(Just)" after the "Highly Recommended", which has again never been seen before. But, to me, this contradicting final rating (against the presentation in his Conclusion) doesn't look to be making any sense at all.

Monday, December 11, 2006

Does the Number of Bits (in Digitization) Matter?

When Pentax always talk about the Analog to Digital Convertor of K10D has 1024 times more tonal levels recorded when compared against conventional/typical DSLRs, what does this actually mean? And, what're the benefits? Practically, how significant this would be and does this really useful, or not?

First of all, as I have included in the Introduction part of my Homepage the following links, these two (great, clear and useful) articles are something that must be read for anyone who are interested in the topic of digital tonality (and anything related to this topic):-



With a few of the basic concepts in mind, assuming the CCD and ADC combo is calibrated for a full (dynamic) range of 4 EVs for all the digitized tonal levels, i.e., from Zone III to Zone VII (-2EV to +2EV respectively, with 0EV at Zone V, which is the middle of the range), I summarize the relationship between the Number of Bits in Digitization and the Distribution of Recordable Tonal Levels along the Brightness Histogram, as follows (linear response curve within the ADC is also assumed):-


Now that just like what Mr. Norman Koren and Mr. Michael Reichmann have illustrated in their respective articles, it should be noted again most of the recorded/recordable tonal levels are "condensed" at the brighter side or the "right" side (of a histogram). It can be noted also when the brightness levels is doubled, the (sub-)total number of tonal levels within the brightness range is doubled and ditto when halved.

Do note that if the ADC with the CCD is to be calibrated for more Zones, then the distribution of recorded tonal levels will be even drifted more to the right side of the histogram (while the total number remains the same). Nonetheless, the assumption of -2EV to +2EV is fair and practical enough for a traditional light recording media like slide film which has more or less the same (narrow) latitude in exposure as digital imagers.

So, with reference to the figures in my above table, the total number of tonal levels is calculated by 2 to the power of (the number of bits). It can be seen that the total number of tonal levels for a 22-bit digitization device is a tremendous figure. By dividing the 4,194,304 (which is the theoretical figure for a 22-bit device) with 4,096 (which is the figure for a 12-bit device), the difference is 1024 times. This is what Pentax emphasize on and here is how it comes.

However, as explained in my last article about the ADC of the K10D, the highly oversampled bit rate (which I would say it is overkilled) will be downsampled to 12-bit *shortly* after the digital data are passing out of the DBE (Digital Back End) of the ADC. This number of bit is what a RAW file of the K10D can give. And again, as what Pentax have also told, at the same time, but not explicitly, it is only 1/1024th of the original data of the 22-bit ADC! (just because the K10D RAW files are *also* in 12-bit, as against 22-bit).

The good thing here (about the K10D) is that a linear curve is not mandatory for the ADC of the K10D (again, see my last article, remember the "knee" points function?) so oversampling can provide more data for adjustment and correction. For the bad thing(s), I shall talk in the following paragraphs.

So, how important is this "number of bits" figure on the image quality and the tonal response (smoothness in transition, etc.)? It is very trivial that the more levels it records, the smoother the tonal quality and response it would be. However, it is the main weakness of *any* digital camera that the number of tonal levels at the shadow areas are much less than those counted at the brighter parts, i.e. the highlights, owing to the primitive nature of CCD/CMOS imager, which is a linear square law detector.

As such, assuming *perfectly* ideal exposure which means that an evenly spread histogram is obtained, *at* the time of picture taking, then most of the tonal levels are recorded as *useful image data*. In contrast, if underexposure happened or just that the highlights part of the picture are out of interest by the photographer, then the limited number of tonal levels at the shadow, say, only 273 nos. for a 12-bit RAW, at the darkest quarter of 0-63, then this limited number of tonal level steps, as recorded in the RAW file, will be "stretched" to re-build the whole picture, resulting in visible noise and lack of smoothness of tone transition.

So, in short, the number of bits from the DBE (actually it is also what the RAW file could contain) is very crucial for what later on the user can tweak a picture or how the IPU (Image Processing Unit) of the DSLR can process the image, for a better looking one.

Well, at this point, what I must emphasize (again, as always) is that an accurate metering and exposure system of the DSLR is of prime importance than anything else, given that the number of bits of the RAW file is the identical. In contrast, if the RAW file has more bits, then this will open up significant more room for post processing of the RAW, just see the 14-bit example of the Fuji S3 Pro in the above summary table. It has four times more tonal levels even at the darkest quad of the histogram.

Nonetheless, for a properly exposed digital image which requires little adjustment of the levels, the number of bits will then become insignificant. The fact is that most output format and devices have only 8-bit per channel (24 bits for all colors), these include JPEG files (which Fuji Frontier Laser Photo Printing Machines accept as standard format for printing) as well as the latest PC DVI interface (which is 24-bit only for its TMDS transmission protocol):-


In fact, most cheaper LCD panels/monitors are of 6-bit per pixel only and by dithering tricks of four pixels to form one, they can yield a maximum of 16.2M colors in the published specifications (instead of 16.77 million colors for true 8-bit panels). My current LCD monitor used at my home is an EIZO / FlexScan S1961 which has a true 8-bit per pixel panel and an internal 10-bit signal processor which is already very good in tonal and color reproduction.

Indeed, I always find that EIZO products are designed and built *very* accurately, for my experience with their various models over years. To compare, previously I also bought a Samsung 770P top-of-the-line (also) true 8-bit LCD monitor but which IMHO by no means can match with the EIZO, in terms of color and tonal accuracy, despite the published specs are quite similar. This story strongly reminds me again that sometimes specifications don't tell much but only the actual performance as well as the level of accuracy of a product are the true important things that really count.

So, in the end, you need a high bit *output* device to output your high bit pictures, if any. Actually, DVI cannot give more than 8-bit (the transmitted data are in 10-bit, but the remaining two bits is for the transmission protocol, but not contain any picture data). HDMI can have more bits in 12 numbers, but currently very few PC display cards as well as monitors support this. Of course, one would argue that why not use CRT displays which has more colors? My humble opinion is simply that to set up an accurate analog color output system is not for non-professionals nor most home users! Even more, to maintain and calibrate such a carefully set up system is again not an trivial job!

Last but not least, if you still have some unresolved puzzles about the basic concept(s) in your mind after reading all these here and even after reading the above two provided (important) articles written by Norman Koren and Michael Reichmann, you may wish to read also my article, "How Lights are Mapped into Levels" (contained also in the "Links" section of this Blog), which I hope I have written in an "easier" way.

Thursday, December 07, 2006

Report of Burnt K10D RTF (Built-in Flash) Continues

Further to my previous Blog entry with an analysis on the previous reported K10D RTF burnt case, by a new K10D user, here is another (unfortunate, again) user who have just reported the death of the RTF of his new K10D of two week old:-


So, as the replying poster comments, "I am surprised Pentax haven't nailed this (QC?) problem yet." and it is "Rather Typical for Pentax DSLRs".

The most worrying thing is that the victim writes that it has been confirmed that currently there is no spare parts for the broken part and that even there is one, he will worry again about the reliability of the replaced part, just because it might be the same in nature.

The Maker of the "ADC" and "IPU" Chips used in K10D

After I posted my last article of “The K10D Secrets (Part 2) - The Bridge: ADC” yesterday, various people have responded that they had the doubt if Pentax really used the NuCore devices in the K10D, or not.

As I have mentioned in my last article, this is an *officially unconfirmed* *rumour*. By the most primitive definition, a rumour is something that you can’t get it confirmed by formal means. However, I really can’t understand why while most people can accept for the also a *rumour* (by definition) that a Sony 10MP CCD is being used in the K10D, some particular people cannot accept for the possibility that the ADC and IPU chips are actually come from NuCore.. Just because the company are not as famous and large?

Actually, this topic has being discussed repeatedly for so many times since late August, at various Pentax forums on the net. To sum up those numerous discussions, the following are some relevant factual findings for digest, for anyone who are interested:-

1. Appearances of the Chips

First of all, you can have a look on the chip appearances for the photos posted at the Dpreview K10D link below:-

Well, considering the close relationship between Dpreview.com and any camera manufacturer, I consider the photos and the associate descriptions published on the page to be at least semi-official, frankly speaking.

Now that first look at the “ADC” shot posted at Dpreview:-

.. and then compare it against the photo of the NuCore NDX-2240 chips in their technical catalogue:-

Next, look at the “PRME” engine photo posted at Dpreview:-

.. and then compare it against the photo of the chip in the NuCore SiP-2290 catelogue:-

It should be noted that there are no silk-printed marks on all the chips in the Dpreview photos. As such, all the readers will have no idea on the codes and the types of the chips used as well as the make. Anyway, it is very unusual for those chips used in a product do not have any marks and numbers on them, unless just in case those are intentionally left out or wiped out for some reasons.

Just for your further reference, here is a photo showing what a “normal” electronic chip should look like on its package:-

At this point, I bet that you should at least have some brief ideas after comparing the pairs of the different photos. So, simply merely judge by yourself!

2. Information about the Chips, as described by Dpreview:-

22 bit Analog to Digital converter
If accurate this could potentially deliver a very fine number of gradations, especially useful in shadow areas. However don't forget that this will always then be downsampled to eight bits per channel for JPEG conversion or stored as 12 bits in RAW. How relevant this '22 bit ADC' is to the final image quality is yet to be proven. ” – Phil Askey (owner of Dpreview.com)

Well, this is exactly the same design and features as the NuCore NDX-2240 12-bit model. Furthermore, as what the official K10D manual tells, the ADC of K10D is in 22-bit but RAW image data is only in 12 bits. But the crucial point is that it should be noted that a 22-bit ADC is not an ordinary thing. So, it may not be a coincidence.

'PRIME' Image Processor
Pentax has followed Canon and Sony in giving a name (a branding) to their image processor. For the K10D this unit is called 'PRIME', that said they aren't giving much away other than to state that it is built on 90nm production process and supports DDR2 (800 MB/sec) RAM which the K10D utilizes (and according to Pentax is the only SLR to do so). ” – Phil Askey

Again, in the NuCore technical catalogue (in the above provided link), it can be seen that their SiP-2290 particularly uses DDR2 RAM. The utilisation of DDR2 RAM is an unique feature of the K10D, as claimed by Pentax, according to the what Dpreview report, as quoted in the above.

3. BTW, here is another quote on "the official “take” on the 22-bit A/D Convertor":-


It would be very interesting to note the used terms of “analog signal re-conditioning” and “oversampling” by Pentax Japan (for what the post says) are actually two of the key features highlighted by NuCore in their (technical) marketing information at their website and in their catalogues! What a coincidence!

BTW, here is some food for thought:- Does the original device maker really matter? I think in the end, only the end results and the actual performance of the camera do really matter!

So, if good chips, which have all those powerful features (I mean the NuCore ones), are actually used in the K10D, it should be a very good news afterall. However, sometimes I still wonder why there are still some people (whom are usually those die-hard blind brand loyalists, as usual) “bashed” me over and over again at the net for the simple facts and technical knowledge which I intended to share, here is a latest example.

My humble opinion is that even though currently there are many "outside" evidences show that the K10D is quite likely having the NuCore chips in it, the OEM brand indeed doesn't really matter in the end! However, it would be always interesting to know more about the NuCore devices, under this scenario, at least for me or probably for everyone who are interested about the K10.

All in all, if the K10D really performs, I would regard Pentax’s engineers have done a great job and they have successfully completed a beautiful system integration, for all those different hardware devices from various manufacturers to software (firmware) programming (Well, Pentax do market the SilkyPix which is an OEM software, in contrast).

Wednesday, December 06, 2006

The Secrets of the K10D (Part 2 of 3) - The Bridge: A to D Convertor

One of the most impressive things of the Pentax K10D, as marketed by Pentax, is the 22-bit Analog to Digital Convertor (ADC). My own first impression was even that it was *impossible*, by considering that the competition only offers 12-bit or 14-bit at most, even for the RAW format files.

Right before the official announcement of the K10D in September, some people around the net had already started to guess about the make/model of this special ADC (of course these people already got known to the K10D specifications, by some "insider" channels), a few of them had been able to spot out that it could be a device designed and made by NuCore. Here is one of the very first posts made:-


Of course, the use of the NuCore device has never been verified by any official means, nor there is any clue in any official documents. However, the rumours continued and still continue on and off. From time to time, the only device, which contains a 22-bit ADC, which people can find and talk about up till now is only the NuCore NDX-2240. Here is a brief technical catalogue:-


Well, if NuCore is compared with Sony, the maker of the CCD used in the K10D, NuCore is indeed a much smaller company which is not quite well known by the public. A quick glance on the company's background will find that it is actually a very high-tech one with joint venture of different vendors, with strong R&D in specific signal processing devices. You can find a list of the joint venture companies in NuCore's company background information page, as follows:-


Despite that Pentax is not one of the listed joint venture vendors, probably engineers of Pentax were wise enough to source and purchase the device "off-the-shelf" as an OEM product from NuCore and use it in the K10D.

Now, let's go into more depth about the NDX-2240 and you can look at the above technical catalogue again. The fact is that it is not just an ADC, but actually it is an "Analog Image Processor", which means that the NDX-2240 does have the ability to handle analog image signals as well as to carry out certain image processing jobs. As you will see following this article, the NDX-2240 is actually an analog *and* digital *hybrid* device.

Referring to the device architecture block diagram on page two of the catalogue, the 22-bit ADC is only part of the NDX-2240 and it is located at the AFE (Analog Front End) of the device (the light pink purple block in the diagram). With the ADC are some built-in analog correction/adjustment circuits/function units, including a primitive "Analog White Balance" which adjust the signal level gains of the R, G and B input analog signals. And then, the preliminarily re-conditioned signals are passed into the digital processing block (the yellow one) for "prevention" of various artifacts (and again, those are actually corrections and adjustments) and then a *low-level* digital "gamma" correction is performed.

The "gamma" correction is actually not a gamma function (which is an exponential function). I think NuCore call this to be the "gamma" just by convention as the term has been widely adopted and is easily understood. Instead of a true gamma function, it is a simple "knee points" correction with linked linear lines. To make it more clearly about how comes the term of "knee", which is actually self-explanatory, just look at the knees of our legs, where a change in angle and direction occurs and the knee joints two linear fixed parts (bones) of the leg.

Afterall, the knee adjustment curve or the so-called "gamma" correction is just a tone curve which relates the input and output signals and define the gain at different levels of the input for the output. According to the information provided by NuCore, there are a maximum of 16 numbers of knee points that can be inserted to define the curve, when all colors are processed "altogether". If individual colors are processed (which practically should be the case, as each individual R, G and B waveforms are being passed out from the CCD and then input into the ADC of the AFE of the NDX-2240), only 4 knee points can be inserted for each individual color channel. (But I have no idea on why it is 4 instead of 5. Where have the remaining 3 points gone?)

Well, for the remaining 3 blocks in the diagram are those supporting functions like timing and sychronisation (the light brown block) or just the bus(es) for internal data transfer and control (the light green block) and the Input/Output (I/O) interface of the Digital Back End (DBE) of the device (the last block), of which data will be the finally output from the serial port of the device, in a serial manner.

Indeed, there have been a lot of "massage" to be applied to the original CCD signals received at the AFE until finally the data are output at the port of the DBE of the device, of which the key functions I have briefed in the above. Actually, there are even more to do by this *processor*.

To name a few about those additional signal processing, which are mentioned in the catalogue, include also smart/adaptive "true black level" detection, "automatic smear detection and suppression" (for charge overthrown case across line(s) of pixels for very high contrast scenes) and so on.

Finally, it would be interesting to note that the NDX-2240 is available in 12, 14 or 16-bit versions, despite that all variants will have a 22-bit ADC, which is used for *internal processing* and adjustment ONLY. Just say if the K10D is using the 12-bit version of the NDX-2240, the RAW file cannot store more than 12-bit as all the extra bits of data have already been truncated once the data are output from the port of the DBE of the device.

In order to verify if the K10D RAW file can contain more bits of data and to sensibly guess which version of the NDX-2240 chip it uses, I have checked the latest version (dated 2006-10) of downloadable K10D manual at the Japanese digital site of Pentax, as follows:-


What I can find relevant is on page 227 of the manual, it states: "RAW data is 12-bit data" and also that on page 51 of the manual it also shows that the K10D RAW file, no matter they are in PEF or DNG, are both same in size, which simply implies both format are in same bits.

Furthermore, it states that a 512MB SD card can host 29 RAW images of both types. So, each image is approximately 17.66MB. A simple calculation can verify if it really contains 12-bit data, the size of the RAW data alone will be: 12 bit x 3872 x 2592 / 8 bit = 14.36 MBytes. And, the extra 3.3 MB room is for the embedded full-size jpeg image and other data like the EXIF. Therefore, unless the RAW file is compressed (which has never been mentioned and confirmed by Pentax in any of their documentation. So, at this moment it should be the case that the K10D RAW files are uncompressed (and there is no option of compression of RAW data neither), the chance for K10D RAW file contains more than 12 bits of data is very unlikely (do note again that the manual have already said that it is "12-bit").

At this point, I hope that I have explained one of the FAQs about why whilst the K10D has a 22-bit ADC, as marketed widely, it cannot have a higher than 12-bit RAW. In short, it is just because the hardware device of the K10D uses probably does NOT support this.

Okay, in the coming last part of this series of articles, I shall brief about the digital Image Processing Unit (IPU) of the K10D. And that I shall reveal what actually the Pentax "PRIME" image engine is.

Update on Dec. 11: To discuss about the significance of the number of bits but as well as the insignificance of the number of bits of a DSLR and its RAW format, I opt to write another article on this topic, in more details.

>> See also: The maker of the ADC and IPU of the K10D

>> Back to Part 1

Monday, December 04, 2006

How AF Errors Can Decrease *Effective* Resolution?

Whilst the Mega Pixel (MP) race have never yet stopped for both the camera manufacturers and the users (whom actually are somehow driven by the camera manufacturers, frankly speaking – consumers tend to follow "trend"), not all the users will notice that the pixel count is indeed not the only factor which will affect the final obtainable resolution (in whatever measurement units). Actually, there are quite some other factors come into play.

Amongst those, I would say the most prevailing factor which affects the final resolution would be the AF accuracy (I will explain following this article why this is so). However, AF accuracy is not something that could have ever been publicized to the end-users by any camera manufacturers. In short, this part of the performance specifications is only known by the manufacturers themselves and those “secret” performance parameters are generally referred to “hidden specifications” of a camera.

As we know, now that the “standard” number of MPs for the current (and the next?) year is undoubtedly 10MPs, whilst 6MP pixel DSLR models are now regarded as “entry-level”. However, before we are going to “chase” after the MP race, there is something more that we should consider. In the following, I shall discuss how meaningful those MP figures would be or not, and how the AF accuracy factor would prevail, as I have said.

Okay, an unarguable fact is that there have been so numerous DSLR users who owned a 6M or 8M DSLR model have already reported that they found AF errors in their shots. Those problems are commonly reported as Front Focusing (FF) or Back Focusing (BF). To me, they are essentially indifferent. Just because both error types simply create out-focused photos. But then, we should be aware that there is simply no perfectly accurate AF system or even MF system on this planet. So, the question is: How accurate should an AF system be made, in order to *match* with the number of MPs or at least with the human eyes?

Before going on, what you need to know about the basic is on the concept about the Circle of Confusion (CoC), see:- http://en.wikipedia.org/wiki/Circle_of_confusion). Well, according to the Wikipedia explanations, we can see that for a 8”x10” printed photo, which is normally viewed at a distance of 25cm, the CoC is 0.2mm. As such, for such a 6MP DSLR picture, the long side of the photo would have 3008 pixels and hence the maximum allowed print density of picture at the longer 10” side *without interpolation* is approximately 300 dpi. Do note that this figure is a *very* realistic one as a very good quality print from the Fuji Frontier Lab Laser Printer is also at around 300 dpi. Still remember the fact of 0.2mm (i.e., 5 lines per mm) which is the approximate maximum limit for human eyes to distinguish an out-focusing blur, i.e., the confusion? Hence, in this maximum allowed CoC diameter, if converted to a number in pixels, for a 6MP DSLR, is equal to: 3008 / (10” x 25.4mm/inch) / 5 = 2.37 pixels;

So, again, what does this imply? It simply means that the AF error can be at most produce an out-focusing blur in 2.37 pixels, that is, the theoretical diameter of the CoC. Otherwise, the taken photo can be seen as out-focused when it is viewed in *full screen*. Do note that this calculated figure generally holds regardless of the size of the screen display or the print. It is because if the picture size is bigger, it is *supposed* to be viewed *as a whole* farther away, and ditto for smaller sizes of the output.

In fact, different DSLR users who complain about the inaccuracy of DSLR AF system, from time to time, must have been able to spot out some problems by themselves (putting aside those minority user errors by beginners). Those spotted errors were either found when they viewed in full screen or during pixel peeping, i.e., by viewing in 100% magnification or go even further, or even both! Well, assuming that those people are pixel peepers first and they actually tried to find problems by pixel peeping, the CoC should be at least in more than 1.5 pixels of diameter so as to for them to find out something wrong. Practically, 2 pixels along a line are affected so that they could see the blur. As a result, 4 neighbouring pixels have virtually become one owing to the CoC blur overlay project on them, on a particular *area*.

Well, here finally comes the most interesting but terrible thing! If one finds out-focusing problems with a 6MP DSLR, that can simply mean that his DSLR has its effective resolution been decreased by *at least* a significant figure of 1/4th, that is, an original 6MP DSLR will become just a 1.5MP one in terms of the effective resolution, a 8MP becomes a 2MP one, a 10MP becomes a 2.5MP one and so on. In short, most of the potential resolving power are wasted. Amongst those, what do think about the differences between an effective 1.5MP, 2MP or a 2.5MP model? :-)

Do note that the required accuracy or tolerance for viewing full screen or for prints for a 6MP DSLR is actually not significantly much less than that when one pixel peeps, i.e., < 2.37 Vs < 1.5 pixels. Thus, if I was the designer of the AF system of a DSLR, I would choose an error of 2 pixels for the CoC as the border line figure, which would be a best compromise between accuracy and for practical use, as well as for the manufacturing cost. Just say for such a DSLR with that intended AF accuracy, typical users will not detect any out-focusing problem for normal use, whereas pixel peepers will have acceptable results of which the errors will not be too obvious. I use the word “compromise” as increasing the AF system precision by too much would be an overkill and the system would be very difficult and costly to make too. It should be noted that with the more pixel count of a DSLR, non-pixel peeping users will not benefit anything much if the AF system is not on a par with (the pixel count). In contrast, pixel peepers will find even be more disappointed as it will be more easy for them to see all those artifacts and errors when they “peep”. So, let’s discuss back for a little bit more specific about the Pentax K DSLR cameras (Well, I nearly forget about my Blog is on Pentax gear :-)). Actually, what I can confirm is that my K100D has a far more accurate AF system than any of my previous *ist D, DS and DL bodies which I owned or used. Anyway, it has actually been confirmed that the K10D does have the same AF system as used in the K100D, according to the previous recent inteview with the K10D design and development team leader, by a Japanese local online media. Here is the source link of a translated version, in English (by a Japanese PDML member):-


Here, I quote again the dialogues which I have just mentioned above:-

Q: As the resolution becomes higher, the focus accuracy and camera shake reduction become even more critical. Does K10D have different approach to to ASF and SR?

A: "Regarding the focus accuracy, the criteria hasn't changed much from K100D. We consider the AF accuracy for K100D being excellent in the first place. Furthermore, at the time of transition from film to digital, the AF accuracy is now determined by the standard of pixel peeping on a monitor, rather than the focus depth based on the allowable circle of confusion as in the case of film camera. We heard from some quarters that the AF speed for the models prior to K100D was slow, but we have reevaluated the AF mechanism and controls etc for K100D, and realized the increased response speed while keeping the focus accuracy." - Mr. Hisashi Tatamiya (Chief Engineer of the K10D Development Team).

It should be noted that when K10D has the same AF accuracy as the K100D is not necessary meant a bad thing. It is because to put it in the other way around, the K100D’s AF system (actually the K10D’s one) can be overkill. Anyway, I have no more information in hands to confirm or verify further about the case.

So, whereas you folks may see daily, particular some K10D users at various Pentax user forums do have complaints on the AF accuracy of their K10D (there is some K100D reports too, but I notice that there are more K10D reports – but then do note that the K10D is a very new camera and it’s also normal to have more users to talk about them), I think my this article can quickly give you some ideas about the case and why AF accuracy is of prime importance, for *any* DSLR.

To be fair, as for a more balanced view, I must also point out that there exist also many Canon and Nikon DSLR users who also complained and complain about FF and BF problems, yet more or less with particular DSLR model(s) or lens(es) or some particular combinations of lens and body which are more prone to errors.

As a final humble comment of mine, I just wish to say that when people are just asking for more mega-pixels for a DSLR, why not urge for a more accurate and reliable AF system in the first place??

Friday, December 01, 2006

The Secrets of the K10D (Part 1 of 3) - The Heart: CCD Imager

In my this new series of technical articles, I am going to write some of the inside "secrets" of the K10D. Well, I would call those inside things the "heart", the "brain", and also the "bridge" connecting the two, i.e., from the CCD, to the Analog to Digital Convert (ADC), and then to the Image Processor Unit (IPU).

As the first Part of this series of articles, I shall brief about the CCD used in the K10D. As you may know, it is a Sony CCD imager/sensor. First of all, here is the simple (marketing) datasheet, in Japanese:-


Well, the model name of the CCD used is called "ICX493AQA". The ICX493AQA is a newer generation of the 10 MegaPixel APS-C sized CCD imager from Sony, which its predecessor is the Sony ICX483AQA that used in the Nikon D200. Do note that the K10D is not the only nor the first DSLR model that uses the ICX493AQA, actually the Sony A100 is the first one used this new model, for Sony themselves.

Okay, let's go through a bit about the information provided in the above factual datasheet. Firstly, the new ICX493 has 2-channels in two pipelines which allow *analogue* pixel data to be "clocked out" by shifting the signal (voltage) levels in each recorded pixel and then propagated in the two analogue chains of electrical waveform, at a clock frequency of 25MHz.

For the (analogue) addressing and sequencing of the waveform chain, diagram 1 on the page two of the datasheet is referred (note the numbered pixels of R1, R2, R3 ... to R8, ditto for B and G). In short, Red and Blue pixels are "queued" and put together in the same channel (which is actually the same "chain", I will have it explained in more details later in the next paragraph) for output and then the Green pixels, denoted Gr (along the Red pixel lines, horizontally), and the Green pixels, denoted Gb (along the Blue pixel lines, horizontally) are grouped together and output at the other second channel.

In more details, The Red pixels are clocked horizontally in the sequence and pattern as shown in the diagram 1, for two adjacent horizontal lines of pixels, from left to right. The first cycle is for the Red lines of two and then the second cycle is repeated similarly to the first cycle, but for the Blue pixels this time (again of two adjacent horizontal lines). The same applies for the green channels for the two type of green pixels. Recursively, the whole frame is hence "clocked" out of the whole CCD arrays from bottom to top with repeating processes, then the data from the two channels is re-composed again, to form a complete composite picture data of the whole frame.

To compare against the older ICX483AQA, which has 4 individual channels of R, B, Gr and Gb respectively, the ICX493 undoubtedly will have a lower output data rate and hence a lower frame per second rate (3.3 frame/s Vs 5.57 frame/s) just because the ICX483 has double the channels but both models run at the same clock frequency of 25MHz. In this connection, it is interesting to note that the maximum number of continuous shooting frame rate of the K10D is by itself limited by the specifications of the Sony CCD sensor, but not the peripheral components within the K10D. But there is a small mystery on the K10D specifications: I actually had got a copy of the Pentax Press Release file well before the embargo released date of 14 September, the K10D specifications contained in it stated that the continous frame rate is 3.3 fps but now that all the published specifications have been updated to 3 fps only. Interestingly, the Sony A100 has also a 3 fps rating but not 3.3 fps, which is again lower than the theoretical maximum allowed rate for the Sony sensor.

Although more channels will lead to a faster frame rate, for the same clock speed, the more channels a CCD has, the more vulnerable the CCD would be for producing artifacts by itself, for the composite picture frame. Just say if the ICX493 which has two channels for the picture data, the whole picture will be re-built by using the two channel data streams. Similarly but in contrast, the ICX483 will require four data streams to build up the whole picture frame. Just in case one or any of the data streams does have some inconsistency than the others, owing to the fact that no two circuitries or (micro-)electronic components like amplifiers, etc. are built and could be built *totally* identical practically, some inconsistency within the frame might be seen for the final composite picture. A good example for this problem/technical limitation is the famous banding issue of the D200. As a remedy, the subsequent ADC and/or the IPU can take up the adjustment and preset calibration (at the factory) jobs, so as to eliminate the undesirable effect(s).

Regarding the "banding" issue, there are actually many causes for the generally called "banding" phenomemons (which are more than one type). I opt to write more about "banding" in a coming article, after I finish this series of the 3 "K10D inside" articles.

Afterall, a two-channel versus four-channel design is just a case of give and take. Whilst the continuous frame rate has been decreased (almost by half), a more consistent the picture quality would be better guaranteed, comparatively. Well, I would prefer the former as still picture quality should be of no doubt more important than continuous shooting, at least for me. Also, 3 fps is not a very slow frame rate already, it should be adequate for typical use.

Secondly, another major advantage/improvement of the ICX493 over the ICX483 is about the power consumption. Now that the 493 requires only 6 Volts to drive and the previous 483 requires 7V. As a result of a lower voltage and an overall simplified circuit(ry), the power consumption has been dramatically reduced by 37%, as claimed by Sony. So, what's the implication of this? Beside it consumes less power which means a longer battery life, more importantly is that there is less heat generated which simply means less electrical noise (and hence picture noise in the final image) will be introduced as a result of a higher temperature within the CCD during operation. As a final result, the Signal-to-Noise ratio of the 493 CCD could be improved.

Thirdly, another advantage of a simplified circuit design is the package size of the CCD component is minimised. The new QIP (Quad In-line Package) has only 64 pins, versus the 80 pins QIP of the 483, which means fewer connection points to save manufacturing cost and increase the reliability (very marginally), too. Thus, the outer flat area size of the 493 package boundary is only 81.8% of the 483 (there is a typo in the page 2 of the datasheet which mentions "91%", as I calculate it to be only 81.8%, according to the actual dimensions provided in the datasheet) and that the weight of the new CCD is only 75% of the old model.

But do note that the gross total light sensitive image area of the 493 is actually smaller for the vertical height (18.42mm Vs 20.3mm) whilst the horizontal length is the same (26.1mm). However, since not all the area of the CCD light sensitive area is used for imaging, as some areas must be masked out for calculating the dark current (to rule out the background noise for the true image signal), the actually "sensible" area and number of pixels remain the same (3872h x 2592v for K10D, ditto D200), which results in a recommended diagonal length of 28.328mm by Sony and thus the multiplying factor is 43.2666mm / 28.328 mm = 1.5273. Just for your further information, the 43.2666mm is the diagional length of 135 film frame which is in 36 x 24mm.

Okay, in the next Part of this series of articles, I shall talk in-depth about the "Bridge", that is, the AD Converter used in the K10D! Please come back later! (Of course, I have done my research already for something to be shared with you folks! :-))

>> Go to Part 2

Updating of my Blog Editing Direction

Recently, I have started for a new poll at the PentaxForums, which I have newly joined, for collecting initial opinions and impressions about my this new Blog page of only a few days in age. I have allowed the entries of "Too negative", "Negative", "Neutral" and "Useful" for voting in the poll.

So far, the dominant voted entry is the "Too negative". In view of the opinions collected, I have decided that I shall include some more "positive" elements (actually, it should be even "more informative") into my Blogs so as to make a good balance within my Blog site.

In view of there are already excellent Pentax Blog pages such as PentaxLife.com and OK1000 which do report promptly the most updated Pentax gear related news from time to time, I think that I shall contribute for elements of a somehow different kind and in a somehow different way. You may notice now that my Blog page themes in the title of the Blog have just been updated. I have added also for the "Technical Articles on Pentax DSLR Bodies and Lenses", in addition to the original "News about User Feedback on Pentax Photo Gear, Potential Issues and Possible Areas for Improvements"

In short, for the new direction of my Blog editing, there will be two main elements. I shall first try to share and discuss the technical aspects on the topics related to Pentax DSLRs and the technologies used by Pentax. But yet, I shall still continue to try my best to report all the significant user feedbacks about issues they found with their new Pentax gear, mainly (but if there are also significant issues for the old stuff, I shall also report). For the latter, as you can see for my posted articles, I shall try to discuss some of the technical stuff behind in the light of trying to make an analysis on the possible reasons for such issues, so as to suggest some possible feasible solution(s) for those reported problems, and most importantly, to suggest for those areas which needed improvements by Pentax in the coming future products and firmware updates.

Okay, I shall publish the first of my first series of technical articles about the inside of the K10D shortly, of which the contents and information that will be shared are not yet widely known by most Pentaxians or other interested watchers. Just keep an eye on my page and watch out! I guarantee that you will not be disappointed or even be surprised! I have the confidence that you will find the published information interesting and useful and will not be regarded as "negative" (again) at all!

P.S. So far, I've found that the place of PentaxForums a very friendly one. The site owner did reply my first post in a very nice and friendly tone very shortly after I made my first post the day before as well as I found that the first replies from other members to my initial three posts are very friendly and I can feel that the people are *very nice* over there. In contrast to what I experienced when I made my first (very simple) post at the Steve's Forum earlier this year, one of the site moderators had "popped up" and sent me a private message which I did feel that had a sense of "warning" to me. (but I just wondered why he needed to tell me that and why he said so..)

At the PentaxForums, I note that there are quite some old Dpreview.com forum pals there, though, However, up to this moment, they have not yet "jumped" on me as they (usually) did in the past at Dpreview.com everytime when I made an opinions. So, a different place really makes a (big) difference!

What a nice place of the PentaxForums.com! At this moment, I would have no reservation of any kind and would highly recommend any existing Pentaxian friends or all potential Pentaxians to join the place for knowledge and discussions. Finally, do note that PentaxForums is basically a non-commercial site which makes me feel at least comfortable and safe to speak and to "contribute". See the following message quoted from the site owner on the front page of their site:-

"As you can see, our site has no ads, and we're not here to make money. PentaxForums.com has a single goal: to create the ultimate forum for Pentax users accross the world! Enjoy the site, and we're looking forward to seeing you around!" -

Wednesday, November 29, 2006

K10D Auto ISO finally works with EV Compensation?

Here is a good news about the K10D. A new user states that the EV (Exposure (Value)) Compensation function does not defeat the Auto ISO function, finally:-


I think in order to firmly confirm the case, this is to be verified by more than one user, though. Moreover, as all Pentax user manuals of their DSLRs have *never* mentioned anything about this long-lasting significant "limitation" (strictly speaking, it can be regarded as a "bug"), we are actually having no idea from official source if this time it really works or not.

The more interesting thing is that I did report this problem on the Net back to early 2004, about my *ist D. However, I did receive numerous surprising responses like: "DSLR users should learn and know how to choose ISO manually", or "it is of no big deal" or "Auto ISO is for P&S shooters only", or alike and etc. Of course, there were even some more vigorous responses to my (just simple) statement of such a trivial design "limitation" which is indeed causing much inconvenience and is simply annoying.

While this problem has now been widely recognised by many Pentax DSLR users since it has been with us for years, and also with the growth of Pentax DSLR user base, I deeply feel sorry for Pentax that they have not improved their firmware for such a minor unthoughtful design for such an unreasonably prolonged period, even after their *ist Dx series of cameras have been discontinued. And still, the inability still holds true for my K100D.

Hopefully, this "improvement" is true. BTW, anyone can verify the case and re-confirm here?

K10D Bulb mode cannot hold longer than 32 seconds?

3 different users reported that their K10D cameras could not hold "long" exposure more than 30 or 32 seconds in the Bulb mode, despite that the battery indicator did show full power as well as the battery power was actually not depleted:-




If what they said are true, then it is undoubtedly that there exists some kinds of hardware problem and/or software/firmware bug with their units. If Bulb mode can just only be up to 30 seconds, why "Bulb"? In the Manual mode, there is also a 30-second (actually ideally should be for 32 seconds of exposure) setting!

My humble advice is for anyone who plans to use the K10D for real long exposure shooting applications (typically for night scene shootings, not even to mention astrophotography), one must be aware of this potential problem reported. Do try and test fully, hands-on, to confirm if the mentioned problem exists or not before you buy! My final advice is do *never* try to *wait* for a fix for a camera which has some existing problems which cause you troubles which don't satisfy your current need(s), and cannot work for your *current* application(s).

Update (Nov. 30):
Yet another user at PDML reported that the problem was appearing intermittently:-


Actually, the problem of the 30s limit in Bulb mode did appear sometimes in Continuous shooting mode and sometimes with just a quick press of the shutter release button. The user also mentions in his above post that with a longer time of half-press until the SR symbol appeared in the viewfinder, he experienced no problem. (but how come any Pentax K10D or K100D user should turn on the SR function in Bulb mode? It is not recommended by Pentax afterall, i.e., SR should be turned off when the camera is mounted on a tripod!)

Tuesday, November 28, 2006

DA 21 Limited Front Focusing or Back Focusing?

This user experienced an obvious FF issue with his DA 21 Limited lens and conducted a series of simple but yet effective test to confirm the problem:-


In contrast, another two different users experienced BF issue with their each own copy of the DA 21 Limited lens:-


But the common point of all the three reports is that the users are all believing that the problem is mainly associated with the DA21 lens model.

So, does the DA21 Limited itself have some inherited problem by itself? Or, simply all those are just poorly calibrated units from the factory?

Nevertheless, one thing is of no doubt, for a nearly $500 priced prime, if I was the purchaser or even just the user, this would be a big joke to me.

A Case of Burnt K10D RTF (Built-in Flash)

A new K10D user complained about his K10D refused to work with RTF popped up after he had fired a few strobes of AF assistance flashes:-


Actually, his K10D RTF was found burnt and he was upset.

On the other hand, it has never been heard about reports of burnt RTFs with previous Pentax *ist D series DSLRs before, except that the users who reported a burnt and broken RTF as a result of using non-regulated Rechargeable CR-V3 batteries which are of excessive higher voltage than the *ist Dx design that could tolerate. Those RCR-V3 batteries are actually made of Li-ion materials and if they are not regulated, their voltage would be at 3.7V each. So, a pair of which will add up to an excessive voltage of 7.4V, which is 23% more than the intended allowed level, i.e., 6V nominal.

Indeed, Pentax "banned" the use of any RCR-V3 battery because of the above and they recommend no user should use any RCR-V3 in their DSLRs:-


Unfortunately, they "ban" all types of RCR-V3 batteries including some of those regulated types which are indeed performing very well in their cameras.

Okay, let's compare the two different "burnt RTF" incidents, the symptoms are indeed quite similar..

Now that the K10D is the first Pentax DSLR (and SLR as well) which adopts a Li-ion battery, at 7.4V. If the cause of the burnt K10D RTF is to be explained. It should be either one of the following two possibilities:-

1. His K10D has some in-born defects and his unit is just "fortunate" enough to get through Pentax factory's QA system and the QC process, and utlimately arrived in the hands of that unfortunate user; Or,

2. The K10D RTF and/or associate circuitry are not fully proven enough to handle the considerable higher voltage and current from the new (more powerful) battery source. Do note that all electronics components do have a certain degree of errors in values when they are manufactured (which should be within the tolerance of their design specifications). Of course, if more reliable and more accurate (with lower % of errors) electronic components are used, the costs required will be of higher. Nevertheless, just in case if the margin of a circuit design is set too low and marginal, evils might happen.

Anyway, time will tell.. Let's see if there will be more similar happenings (provided that the victims will report and I do think they should report too if encountered) OR this is just an isolated case, that is, there is in general no significant QC loophole as per Case 1.

P.S. Now that I have re-posted all my three messages which the site owner of the Steve's Forum is accusing me of "always" "stirring up troubles" (troubles? what "troubles"??) and must "put me to death" at their premises. What do you think about my these *reports* and *opinions*?
What're wrong with them? And, how about the "Freedom of Speech" (FoS)? Which place(s) on Earth we should have the FoS? (But there is virtually none at these private and commercial sites if they wish to apply *their* "control", frankly speaking.)

Just another very similar but yet unfortunate case, I was banned by Phil Askey at Dpreview.com's Pentax SLR Forum just a few days after I shared about my letter to the Pentax CEO, of which the full letter can be found in the "Links" section of this Blog.

Monday, November 27, 2006

Pentax (K10D) also reproduces Canon-type "Plastic Skin"?

Japanese website IT+Plus of the Nikkei Net posted some photos taken with the production K10D. One of these is a cutie baby portrait photo taken, below is the downsized picture:-


To inspect the full size original image, here is the direct link:-


With the new PRIME image engine created by Pentax for the K10D, it is obvious that Pentax has being tried very hard to catch up with their competitors in image processing hardware and technology. or at least their marketing guys are smart enough to create a new name for their image processor/engine. Nonetheless, the most representative and renowned image engine is undoubtedly the DIGIC image processors by Canon.

However, quite some photographers, including myself, found that whilst Canon DSLRs do often (re)produce excellent resolution, exciting colours with very low noise levels, comparatively at all ISO speeds (and hence some types of photos will look very impressive), some portrait photos looked fake and it is called "plastic skin" in general on the net for these unnatural looking skin representation.

Well, here is a funny joke for mentioning the coming Nikon D90 (which is an imagined model and the article is a hoax, or just for humour), will have a new "plastic skin mode" available! Funny! LOL :=D


BTW, what do you think about this sample picture? Judge yourself..

Effectiveness of Pentax Dust Removal System (in K10D)

The Japanese review site DC Impress have recently tested the production K10D:-


When I inspected the series of the boat photos for the ISO sensitivity test, it was found that there is an obvious dust speck above the top left corner of the hotel building, in the blue sky. I was actually rather surprised when I first found that, especially the shots were taken at only moderate small aperture of f/11.

And then, below is a new K10D user commented that his new K10D already had dust specks seen in his taken images even though he had turned on the Dust Removal (DR) function, whereas another user in the same thread responded and pointed out that his old Olympus E-1 DSLR have never had any dust problem even he regularly changed lenses:-


In view of the above facts, the effectiveness of the Dust Removal (DR) function of the Pentax K10D is actually in question, although on paper it seems to be quite ideal.

Do note that all the production K10D units are quite newly shipped from the factory and thus they should not have been contaminated. Even though just in case some of them are, the DR system should be able to remove them *before* the photos are taken. It is not even to mention about the users will be required to clean their sensors *after* they discovered that there are dust specks in the images taken.

Sunday, November 26, 2006

Why This Blog?

Some Backgrounds

On the Net, there are various places for finding information about photo gear. If an interested user or a potential buyer wishes to gather some information he wants, there are typically two major types of (commercial) websites and then is the minority of non-commercial personal website which he can visit:-

1. Commercial Websites run by "Experts"

Typically, there are numerous "review" sites and some of these are also come with ("user") forums. These sites are mostly run commercially and attract the public to visit so that they can earn their income indirectly from advertisement paid by the camera manufacturers and purchases from "recommended" (associated) shops by their readers.

On the other hand, the camera manufacturers will (e)specially supply test units to these websites for their "reviewing" and thus actually they rely heavily on the camera makers or sales agents for the availability of their test gear. Just say if the test gear comes late or there is no gear supplied, they will have their review put late or no review to come up at all.

The business rule here is indeed very simple: the more visitors or more traffic at the website, i.e., the more increased popularity, the website will have more value and bargaining power to the manufacturers, the shops or any related commercial parties and that they will become influential.

That's just a simple indirect merchandising rule we all know, but sometimes we might have forgotten, just like those traditional "free" TV stations. However, the analogy between "free" TV stations and these "free" internet photo gear review sites is not totally exact. For example, TV stations are regulated strictly by government authorities locally under specific laws for broadcast and media. However, those internet review websites are mostly autonomous and self-governored for their contents, as long as they don’t break the local laws.

Afterall, running this type of websites is indeed not very easy. As there must be a compromise point to be taken carefully between the readers and the parties who pay directly. Actually, those websites must try to provide some information that *considered* to be "useful" by the readers. Otherwise, the visiting hits to the websites will drop and if this situation continues, they can't survive in the end.

A few typical examples of this type of websites for photo gear are the Dpreview.com (currently the most successful one, I think) and Steve's Digicams.com (one of the oldest but I think they are now declining in popularity when compared with their old days).

2. Commercial Websites for User Reviews

Those websites run commercially and the reviews are written by end-users or the consumers. They earn their incomes by selling the user comments and written reports to internet shops, as some kind of more "trustable" advertisement, and also sell to the manufacturers who are collecting user feedbacks.

In contrast to the "experts" in commercial sites, the authors, who are actually invited end-users, are free to write anything up to their own opinions, without any commercial constraints and concerns of their own.

Whilst the comments and opinions contained in those review articles are mostly trustable primitively in nature, i.e., the users will try to tell the public truly for what they think (just because the only reason for them to write is that they want to share their experience), the problem of these written articles by various different persons is on the (in)consistency of comments amongst them.

It is just because these reporting users vary much in their backgrounds such as user level, technical knowledge about gear, photographic skills, as well as their (again different) requirements and expectations. As such, one user thinks that a piece of superior gear may be regarded as ordinary or even inferior by another user(s) or vice versa.

So, at the end, the readers have not much ideas on how to trace the standards and bases which the authors based on, unless they can give more objective presentation such as scientific evidence, instead of subjective comments by words without more supporting grounds.

It should be noted that the site owners for these websites do encourage speeches of both "positive" and "negative" comments as these are truly valuable to both the manufacturers and the readers and these "negative" comments will have no conflict of any kind for them to earn their income.

A typical successful example of this type of websites is the Epinions.com.

3. Non-commercial Websites or Blogs maintained by Enthusiasts (usually those people are the true "experts")

This type of websites are created and run by enthusiastic people who have a good knowledge about photography and gear. They built their own website upon their own drive without any commercial intention and interest involved, at their own money and time, but just for their own sake of interest and hobby.

A good example of this type of websites is the PhotoZone (http://www.photozone.de/), which in recently two years the site owner, Mr. Klaus Schroiff, conducted his own professional reviews using his own resources and by borrowing gear from the site community or on his own gear. However, owing to the limited resources he has, the progress of his reviews are indeed slow to very slow, honestly speaking. And the number of gear tested is also very limited. And that his site have not ever been increased significantly in scale and popularity like those commercial websites could have been, honestly speaking again.

Actually, Klaus has told previously a few times that he would try his best to keep his site non-commercial as far as possible. I fully agree with and support his belief as independency and creditiability are really very important as practically this is somehow closely related to whether the website is intended to make profits or not.

People like Klaus who has a belief on testing his own or his friends' equipment which are purchased off the street is not alone. Another example of these kind of respectable persons is Mr. Thom Hogan, just see his honest "Disclosure" in the beginning of his latest Nikon D80 Review (by Thom Hogan).

So, Why This Blog?

I have been a Pentax SLR and DSLR user for nearly twenty years and actually my first photo was taken in the 70s with a roll of B&W film. For years, I am truely impressed with the unique optical characteristics, excellent optical performance as well as the build quality of those better Pentax glass and all of their SLR bodies I own.

In the digital era, my experiences with Pentax DSLRs and digital lenses are in a mixed bag. Whilst those Pentax products are still having some of their unique characteristics in design and produced results, I have being encountered various (in)accuracy, performance and quality control issues from time to time over the recent 3 years, since I first got my *ist D, the first Pentax DSLR body marketed in 2003.

Recently, I am quite interested in the Pentax DSLR body K10D which I think is the most important and significant Pentax product of the recent many years for Pentax. I have done quite some researches on the net daily and also posted my findings and comments on different net forums as well, such as the Steve's Pentax/Samsung DSLR Forum.

A few days ago, I have made three posts at the Steve's Forum for three different subjects/topics, just for the first time, about the Pentax K10D, for my latest findings on other website articles or forum discussions. However, the site "administrator" or the owner deleted those messages within two days, including a re-posted one.

One of the site "administrators" called "JimC" was "kind" enough to inform and "warn" me that the reason for the deleting action was because they regarded my posts were too negative to appear in their forums and they thought that I did consistently posted "negative" contents which was not allowed and strictly prohibited. So, I know that they are doing their "moderation" jobs in a strict but very biased way so as to filter out any unwanted messages, which someone do not want to see (as Mr. Jim C also told me that he undoubtedly considered that I was a "trouble maker"). IMHO, this is simply called *censorship*.

Whilst Mr. Jim C did say clearly he (just) wanted to send a warning message to me, someone else of the Steve's Forum banned me shortly so that I could not even to make a reply to his "warning".

Previously, I have very similar experience at the Dpreview forum. So, my these (maybe unpleasant) experience let me clearly learn that if I want to share my findings and express my opinions freely and faithfully, I must set up my own website or blog page.

Actually, I have done this already and my homepage was set up last year (URL: http://www.geocities.com/ricehigh). However, I find that to replace the role of those discussion forums which the more popular ones are mostly run commercially (Type 1 case above), it would be better to set up a blog, as those news and user reports come up daily or weekly which means that timing is critical when those news are happened, especial for nowadays fast changing world of photo gear.

Okay, let's go on with my this blog. In the first three news, I shall publish again the contents of my 3 deleted posts for sharing and open discussions are mostly welcomed.

Whenever I have the spare time in the future, I promise that I shall update my this blog from time to time. However, do note that I shall concentrate mostly on user reported concerns, potential problems etc. which are mainly found around the net. It is because there are actually so many and too many "positive" tones all over the net (by the brand fans) and advertisement (manufacturers' marketing) and it is surely more healthy to make a balance, although I know that my effort to make a balance might be in vain, as I'm just so "little" in the huge net community. The only purpose of reporting and sharing those is just for an aspiration of letting Pentax know which areas/problems they should improve/rectify in the future/current products, including their camera and lenses as well as the firmware used in those hardware.

I think I have been rather late to learn that posting and "contributing" to those *commercial* internet websites is actually a waste of my valuable time as they would let you speak as long as they like what you say and will select what they want to be appeared at *their* own sites. Well, I must send my deep thanks to Mr. Phil Askey and Mr. Jim C (and most probably should be to Steve) for that I *finally* learnt an indeed trivial but actually important thing so that I can now save my valuable time to truly contribute to the gear users. Hence, I think it is totally meaningless for me to use my time to "contribute" to their commercial websites anymore to help them make their own money.

Instead, I hope that I can help directly to all the true users and all the potential buyers of a certain (Pentax) product which must be a wiser act for myself. And I am sure that for the coming days, my efforts must be more contributive than those ever in the past.

>> See also: Updating of Blog Editing Direction