Originally posted by SyncGuy I believe so.. But with that as the company's philosophy, that's why i think they are not too keen:
1) on producing many lenses with wide apertures - this would help in subject : background separation, which is not important in landscape
2) FF - which brings about the benefit of background : subject separation and also minimizes distortion/compression due to using a wider FL to obtain a similar and wider view when compared with larger format. (think 50mm vs 85mm with exact same composition or 28mm vs 50mm)
PS: Please don't mistake my post/points as bashing Pentax.. I'm just listing my own opinion for objective discussions which leads to my own decision in my photographic journey and discovery.
I do agree with you, but with a caveat. With digital cameras, Pentax has almost forgotten wide apertures, so it seems.
However, I see two major reasons for that, and I think they are quite valid. Not that I'm trying to defend their choices, but this is based on my experience during all this time of use of Pentax digital equipment.
1.
SR technology. Wide apertures make lenses big, and IS inside of them makes them even bigger and heavier. To have
a different value proposition than Canon and Nikon and clearly differentiate from them — from two major DSLR manufacturers — Pentax invested in the SR technology, to gain shutter speeds lost when using 1-2 stops slower glass. But, a camera + SR + smaller (albeit slower glass) = increased portability and reduced overall size of the system, shutter speeds retained. This is why Pentax is still in the game and makes DSLR photography interesting.
2.
Focusing. On an APS-C camera, available DoF is 50% thinner than on an FF camera using the lens of same aperture and focal length. That makes focusing, using wide aperture lenses, even harder than on an FF camera. By 'slowing down' APS-C lenses, the focusing game evens up and the DoF increases, which yields in better keepers score. So it is technically wise decision that, for starts, allows more people get more focused-in shots with a Pentax APS-C camera.
Isolation of a subject you talk about, however, is very dependable
on the quality of the background in the image, not the aperture per se. If a photographer knows how to compose a good photograph, Pentax APS-C lenses can isolate subject well and OoF area can look delicious. I base my experience on the use of DA40 and DA70 lenses, which may be described as 'slow' but which are of great optical quality. Isolating a subject is a special type of photography, not something every person should do every day and in every occasion, as it often yields in boring photographs with subjects totally isolated from any reality around them. A good quality photograph makes a connection between the subject and its background, as the narrative aspect of the photograph should always be first in mind and transcend any technical 'prerogative' or a visual stereotype.