There is always a good reason for people who need a DSLR, it is because the lenses of a DSLR system are interchangeable and that the lens lineup of a DSLR constitutes the most important part of such a system.
Now, we can have a look at the current lens lineup as offered by Pentax:-
http://www.pentaxslr.com/lenses
In fact, one will not be difficult to spot that Pentax's current lens lineup has no prime lens which is longer than 100mm and actually that "longest" prime is not a tele-lens neither and it is just a standard 100mm/2.8 macro lens. So, what're the remaining offerings at the tele-side? Well, there are two lenses which the Pentax user can still choose from, but both are just slow consumer zooms, namely, the DA 50-200/4-5.6 or the recent DA 18-250/3.5-6.3, which is widely believed to be a Tamron OEM variant anyway. So, if one don't mind to have such a slow and low-grade zoom (well, again, not even talking about primes), the longest focal one can get is just 250mm, but at f/6.3, with the inferior image quality which can be expected for a 13.9X "super zoom" used at the extreme end focals.
Of course, particular people (usually those brand defenders/blinded brand loyalists/brand fans, or whatever you could find a term to best describe them) would start arguing that *they* do not need to buy new or current lenses, they could just choose to use old lenses. But my opinions are simply that: 1. It is not an excuse for inadequate choice of lenses under the current lens lineup which are in production; 2. Old lenses are not fully supported by the current Pentax DSLR bodies as they were designed to work and function nor these lenses can enable all the latest features as contained in the current DSLR bodies, say, for the AF and AE or even Flash Exposure departments.
Actually, if one looks back Pentax's history and their offerings on those SLR system lens lineup, one would easily discover one sad fact: There has never been a while in Pentax's past history that they lack a complete lens lineup with such a limited focal range and the lack of useful primes (which *were* what Pentax truly excelled in themselves) than the present situation.
Just look at again the Pentax's great stuff for the past generations of the lens lineup, since the late 50s when they made their first SLR:- http://kmp.bdimitrov.de/lenses/index.html#data, then one will know immediately for how weak the current Pentax lens lineup really is.
The funny thing is that if you also look at my own Pentax AF lenses collection, then you will see that actually I have a more complete (or at least more balanced) lens lineup than what Pentax is offering now, especially at the tele-side and/or if those lenses are used with a Full Frame body. Nevertheless, most of the excellent FA film lenses in my own lineup have been discontinued by Pentax in recent years, since they launched their new DA lens production line in Vietnam.
Well, again, those particular people will start to mention about that Pentax has a lens roadmap and they will add new lenses in the future. Yes, I think we all know that. Below is the latest revised lens roadmap by Pentax:-
http://www.digital.pentax.co.jp/en/lens/roadmap.pdf
Now, there are new DA* tele primes to come. But if one have been reading the past lens roadmap updates with a more careful mind, one should have also discovered that now that the latest Pentax lens roadmap for those "future" lenses are now have no "tentative dates" for their targeted release times, if any.
Furthermore, there is yet one big problem with the planned Pentax's system if one bothers to compare it against what Canon, Nikon and Sony has been planning and are offering for their lens systems, that is, no one will make the telephoto side of their lens systems to be in APS-C format, at least not with the same nomenclature as what Pentax has planned for the "DA*" tele lenses. With a DA name, no one can guarantee that those new lenses, even if they are really to come (but when?), are actually Full Frame compatible, or not. BTW, has anyone ever been able to see an EF-S Canon tele lens or a DX formated Nikon tele?? (which doesn't make any sense at all IMHO..)
Well and well, people would ask why "Full Frame compatible" is so important? In fact, Canon, Nikon and Sony are surely having better foresight in planning a system to cope with future Full Frame bodies which they have been planning or simply have already implemented. In fact, the Full Frame trend (or the "Full Frame Train") seem to be the ultimate way to go in the foreseeable future. The C, N and S are at least mind corrected marketing wise, or even technically wise, unlike Pentax, who seems just know to insist on an APS-C development even though even those of their previously promised APS-C lenses are now just paperware which has nowhere to come.
Last but not least and in addition, what I feel indeed rather disappointed (again) for Pentax's lens lineup is that in the past I was always felt proud of being a Pentax user for having the choice or even owning quite some of the best valued and optically excellent and uniquely characterised lenses of Pentax which other systems lacked. But now if one with a more careful mind and without any stance who judges and compares different systems, he/she will not be difficult to learn that Pentax lenses, even DA* zooms, can be purchased as Tokina variants in C and N mounts at much cheaper prices but with similar optical performances and characteristics for all those "co-developed" (as verified in various published reviews and tests), and even the latest Pentax's offer can be found as a Tamron 18-250 super zoom in C or N mount, too. (But Tokina and Tamron just haven't offered those lens models in Pentax mount!)
So, after all and all in all, the big question is my mind is: Why Pentax NOW? And how could and should the Pentax DSLR system be chosen and be considered as a complete system?
You may think that I might be saying too many things that are considered "negative" about the *current* Pentax system in the above. But anyway whether you like the above or not, all these are *facts*. Nonetheless, I would still try to be contributive for my own insight and comment for how Pentax can be alive out of the current difficult situation. I can think out of a possible way or even maybe the only way for them to compete again with others *again* in the future: That is, to re-build/re-setup the old FA film Full Frame lens lineup for lens models as needed (especially for the primes and the tele-side lenses they are lacking, which I think they are theoretically capable of and the re-design works would be minimal, technically) *and* try ALL of their best efforts to make a Full Frame DSLR body - even though it shall not come eariler than the Sony, but should not be (much) later than them. Otherwise, when Canon, Nikon and Sony all have affordable FF DSLR models in the foreseeable future, Pentax would probably die in the end. Note again that C, N and S all have a complete lens lineup for *both* APS-C and FF but Pentax has actually not yet completed even their APS-C lineup (but they were however too "roughly" to decide to discontinue all those old film lenses, especially at the tele-side). My humble opinions and my two cents..
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