Originally posted by mecrox The difference between crop and full formats looks pretty real to me. One is distinctly larger than the other. Artificial, you say ....
You're being obtuse - we were talking about the lenses and their mounts, not the size of the sensor. I shoot both formats, you - well, I don't know about.
On other platforms, you can find for instance that older Nikon F lenses can mount but not be autofocused by a Nikon APS-C camera - only the top models have screwdrives in their bodies. This is not a Pentax problem. I don't think you can put Canon EF-S lenses on Canon FF bodies, either. Again, this is not a Pentax problem.
The new Pentax zooms are not DA or FA, they are D FA.
Originally posted by mecrox
You keep forgetting that this started with a consideration of the question of modern lenses in the context of steadily improving AF on APS-C. Something tells me that most APS-C customers are unlikely to buy the DFA 70-200mm as their go-to telephoto on crop format.
Why not? Its performance, weight and price is completely typical of a professional f2.8 70-200 lens.
If you want a cheapie, the upcoming 55-300 is APS-C, has internal motor and a new aperture mechanism. I thought you said Pentax were doing nothing new in APS-C? It can pair up with the 18-50 collapsible, yet another new Pentax APS-C lens, for a standard two lens kit.
You might not think much of the DA*60-250 or DA* 50-135, but I do ... I've bought the latter.
And read the D FA 28-105 review here. It's sharp across the frame, internal motor, affordable, and a great size - practically an update of the beloved 18-135mm.
Originally posted by mecrox The DA* 55mm was designed as a portrait lens. It has a high price, a long focus throw and by modern standards an out-of-date motor. My guess is that it would not be many people's first choice of walkaround lens on a crop-format Pentax with AF to the standard of a D500. What they'd be more likely to prefer would be around 35mm f1.8 on FF (50mm on APS-C) with a fast motor. But there isn't one. Looking forward to its release over here.
I find it to be a sensational portrait lens on APS-C. You talk about a walkaround, but remember I use it as that on my K-1. On my K-S2 I resort to the FA31. Poor me! :-D The beauty of the K-mount is that for that FoV there's a great lens for everyone - it can be the DA35 Macro or the Sigma 35mm Art or the old K28 f3.5. Note that two of those three are actually full frame.
It sounds like you have not read about the Pentax D FA roadmap. Let me quote:
"The D FA roadmap above hints at five new D FA lenses expected in 2017 or later: wide-aperture ultra-wide, standard, and short telephoto primes, a wide-angle prime, and a fish-eye zoom. The exact specs of these lenses remain unknown, but it would make sense for them to cover popular focal lengths such as 24mm, 35mm, 50mm, 85mm, etc."
Are you still wringing your hands with worry?
As for the D500 comparison, shame on you! You're asking Pentax owners to pony up $2000 for a cropped sensor camera? I suspect that's a very small percentage of a very small percentage who are willing to do that.