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Friday, October 08, 2010

A*50/1.2 Vs DA*55/1.4 - What Would You Choose?



Here is a new poll I think to raise. Both lenses are great optically (provided that you get a good copy nowadays for those units AIV (produced in Vietnam)!) and both are actually still in production.

The A50 is half-stop faster but it is just an old MF lens. And on APS-C, its f/1.2 aperture will provide shallower DoF that could be closer to that of a 85/1.4 on 135 Full Frame. The DA*55 is a bit slower but it has AF. It uses SDM, though, which is infamous in accuracy, speed and reliability. The DA*55's focusing throw is long and is no different from a MF lens actually. Furthermore, after the SDM is dead eventually or suddenly, the DA* will be no difference from a MF lens! ;-D

Do note that Pentax/Hoya has never officially suggested that the DA*55/1.4 is anything that is designed for Full Frame (against what I have been suggesting them that they *should* make it clear and then *everyone* will win, since years ago!). In fact, I suspected that the lens hood of the DA* is just incompatible on Full Frame, although as for the lens it seems to be working on FF cameras without any problem.

Both lenses could produce quite good Image Quality on APS-C when just stopped down to f/2 and the bokeh will not be bad (depending on your requirements or simply preference!). The DA* is easier to buy and the A50 maybe available only in US grey market or you need to order it directly from Japanese online shops, like at the Mapcamera. The prices are close enough for both, provided that you can find it!

So, here is the *tough* choice! If you just want to buy a better 50ish now in Pentaxland, what will you choose? I mean genuine Pentax! Not a Sigma or else. Btw, the Carl Zeiss ZK 50 has been discontinued.. Okay, let's go!

Would You Choose the A 50.2 or the DAStar 55.4?
A 50 F1.2
DAStar 55 F1.4
pollcode.com free polls


Last but not least, whilst all Pentaxians are encouraged to participate in the Poll, which each vote is made anonymously, I encourage even more that you could reply back and post a "Comment" for the rationale and reasons of yours behind for making your choice - There would be some good food for thought and it is always interesting to see for more opinions and viewpoints of what others think! :-)


Related:-

The Very Different Fates of Two ex-AOC Top Optical Engineers

50mm Lens Shootouts

Compatibility of DA Lenses on Full Frame

A50/1.2 is Now Made ("Assembled") In Vietnam

Where are the Pentax DSLRs and Lenses Made?

FA 31 Limited: Assembled in Vietnam Vs Made in Japan - Case Studies (Part 1)

FA Limiteds: Made in Japan Vs Assembled in Vietnam - Continued (Part 2)

Comments (24)

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The DA*, of course. With it's accurate AF, it would work much better than trying to manually approximate the focus on those small viewfinders.
this is a no brainer. I've seen that 55 1.4 in action and it truly an amazing lens. I have the k55 1.8 and love it.
I'll have both please...
1 reply · active less than 1 minute ago
So, if you have to choose one and leave with the other..
Without having to pay for it the DA*55,

I've got a smc 50 f1.7 and I on very very small occasions use it at 1.7. , almost always stop it down. So a 1.2 vs 1.4 doesn't make that much of a difference.

The only reason fot the DA*55 would be the AF as good or bad as it is, you can always MF if it doesn't do the trick.

Just My 5c
3 replies · active less than 1 minute ago
The DA*55 has far better sharpness from f/1.7 to f/4 than all the Pentax 50.4 and .7! But sometimes what's the point of corner sharpness for doing portraiture at larger apertures, anyway? :-)
When the corner is not sharp, there will people say a DA* is not sharp at corner...
But when the corners are sharp, measurbators like Me will be saying that the new DA* is sharp from corner to corner! ;->
Voted DA*, as I already have the A 50mm f/1.4, and M f/1.7 (+helioses), and that I do not have the DA* 55mm. But even if I hadn't those old lenses, I would still go for the DA* because of the smooth bokeh & the WS & the fast focusing / that's just more useful all in all :).
1 reply · active less than 1 minute ago
The DA*55 is not anything considered fast for its AF. But of course, it'd still be better than doing focusing manually.
Surely A* 50/1.2.

It has smoother bokeh, while DA* 55/1.4 gets sharper image but with MUCH more spherochomatism (and this ruins final image).

Also DA* is SDM - no way.
1 reply · active 753 weeks ago
:-) You read my mind !
There is some istakes here...
A50 f/1.2 is only 1/3 stop faster than 55mm f/1.4, not 1/2 stop. Also, a 50mm f/1.2 will be far from a 85mm f/1.4 on FF, it is the exact equivalent of a 75mm f/1.8, so let's say roughly a 85mm f/2!
Then, 55m is longer, and a quick calculation in DOF master say show that there will not be that much difference in the result of these both lenses (for a focus at 2m, near and far limit of focus is 4cm from focus point for each lenses).
By the way, even if you don't like SDM AF, at least it will be more accurate wide open than your eyes through the little viewfinder in manual focus.
So no brainer: DA* 55mm (even if I prefer the look of the A*50mm ;-) )
1 reply · active less than 1 minute ago
1.2 is the square root of "1.4" which is yet actually the square root of 2. So, the difference is just 0.5 stop. Alternatively, you can divide the two, i.e., 1.4 over 1.2 and then take log 2, then you will get 0.5 again.

As for the DoF, you will get the same effect with the same AoV (Angle of View) *and* the same effective lens diameter size. Well, we all know that 50 and 55 have a 5mm difference. But if you had to calculate and compare, only the 55 is close to a film 85 (which is actually just equivalent to a 84.4mm on APS-C for its actual AoV) with an effective diameter of 39.3mm which is f/2.15 (but not f/2.0) of a 84.4mm lens on Full Frame, strictly speaking and to be precise.

Furthermore, the 50mm lens on an APS-C crop camera is equivalent to a 77mm lens, not a 75, if everything is to be more accurate.
... if then...

I'd pick the A* 50/1.2 It's better build and probably will last longer than the DA*. Although I consider that to be an excellent lens too. In the end, I'd rather have a lens that stays in one piece than whatever advantage the DA* might have. There's no substitude for a full metal and glass construction...
Neither. I have the A 50mm 1.4 that I picked up cheap, and I have to say I would be concerned about the 1.2's depth of field wide open (and I shoot my 50mm wide open.

I have a focusing screen, and love the fact my K10d will tell me if I have it in focus.

Otherwise, I would buy the FA 50mm 1.4. The fact is whatever company you look at, their old film-derived 50mm are still the best, and have the best price point. Nikon added to their lens lineup with a G, and it was soft compared to their old lens. Oh, and talked with a Canonphile, and he said that their 1.2 50mm is crap.
Focusing w/ K10D @ f/1.4 is very tricky... Even with focus assist... I just sometimes miss my old Nikon FM, which was way more precise to focus manually, and in which blurred parts looked as blurred parts in the viewfinder !!!
Does anybody have an experience with a split image replacement focus screen ? I would like to buy one since long time now, but I'm not sure if it is really improving focusing over the in-camera focus confirmation... Especially shooting wide open !
5 replies · active 753 weeks ago
I do, this is what I have, and use a number of manual focus lenses on my K10. Its exactly like my old ME Super, except with the assist it gives me confirmation/////
So, when you align the two parts in the viewfinder @ f1.4 (nose / hair, or other detail used to focus), you get exactly the focus where you made the alignment ? I should then consider to buy such a screen...
K10D focus confirmation for me does make too much errors (in low-light portraiture especially), and I can't see the focus plane position and moving in K10D and K-x viewfinders (like it finely enough in Nikon FM or perfectly in Mamiya RB67)...
Like I said it works great. I bought it last year, itching to use my old mf lenses more, and utilize cheaper mf lenses compared to their AF equivalents. Also helps me use my AF lenses in those low light situations (or when the AF is just having issues..

So far the results have been great. I just wish the screen worked in a K7 or K5, but they have different screens. Like bundling the IR remote with the camera, I think Pentax would be wise to include this style screen with their cameras compared to the glass they now include. You take a Kx and some mf lenses, and you are as clsoe to the size of the old compact SLRs as you can get.
This is normal for the focusing screen design of modern DSLRs (brand regardless). See my previous case studies:-

http://ricehigh.blogspot.com/2007/04/when-focusin...

http://ricehigh.blogspot.com/2009/01/when-focusin...
Don't make it a hypothetical vote:

Because... ...I already went out and got one! a DA "star" 55 /1,4 SDM.

Yeah that's right! I inherited some really nice 50/1,7 smc-A lens from my father who "upgraded" to k200d plus kit-zoom 18-55.
I immediately began to love the low-light style of shooting and the extraordinary sharp and contrasty results I got from that cheapo old A-lens. It just had some odd flaw: the diaphragm wouldn't close beyond f/9, any longer!

So I made up my mind after the financial crisis dropped on Pentax-land resulting in a HUGE rise in the price-range of almost anything interesting they still sell when it comes to class. So I decided my next step would include learning about street/outdoor/people subjects which meant I needed something reasonably long and - ideally - wheather-resistend. Because "WR" was the very reason, I got my K20D in the first place (after I saw and liked what my father wrinched out of _his_ K200d).

No camera, regardless of sensor-technology progress, can yield better-than average results without some good glass. My DA55/1,4 thus became my first and only (till this day) all-weather capable lens.

It really was kind a "no-brainer" decision I made. I haven't used it as much, yet. But I am constantly thinking of places and try to visualize shots that will make this little baby shine. And for the rest of the time I simply swap it in front of my camera whenever there is a need for wheather-sealing and some good chance for the 55mm focal length to provide me with the right kind of image-angle at the moment.

Taking photographs with a prime lens really trains the eye! And being able to do that with the added peace of mind provided by WR in both: the body and lens; now this makes it a lot less paranoid for me, especially considering all that money I can shuffle out the window just to enjoy the tools _needed_ for all the shots I am willing to capture.

Maybe I'm a little late to the party. Those are my thoughts. Raw and Clear!
1 reply · active 750 weeks ago
Congrats! Enjoy your new toy!

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