I don't want to start/continue any lynching of StevenG's motivations or competancy here - I just have a fairly simple question in regards to his no-FF frustrations with Pentax...
Your stated complaint with Pentax and professional photography was that your assistant merrily shoots away while your Pentax' AF stutters, farts and falls down in "low light".
My curiosity is how, or why, do you expect simply having a 36x24 offering by Pentax will improve low light auto-focus performance?
I was going to let this go as it's really not my concern and I don't wish to gang up on you - but it's nagging my few remaining brain cells because I truly don't get it.
Full-frame to me means:
a) larger field of view (frame) at the same focal length and distance to subject.
b) increased depth of field at the same focal length, aperture and distance to subject.
c) wider angle of view (perspective) with the same focal length, and field of view (frame).
d) theoretically, better signal-to-noise ratio for the same megapixel count and sensor tech.
Full-frame by itself won't change the AF software algorithm or the number of AF sensor points. Switching to a D700, D3X, 1DMkII - sure you'll get faster AF but there's a ton of electronics independent of the imaging sensor size involved there, not to mention
serious money. I don't know what type of studio lighting you're using but most studio strobes have featherable (new word?) modeling lamps of 150W or 250W that I would
think should overcome any deficiency in ambient lighting conditions.
I think it would be quite fantastic if Pentax were to jump out this year with a direct competitor to the Canikon full-frame flagships along with a
complete line of DA and DA* primes and zooms from 12mm to 1200mm. But I don't understand how the K20D and the available DA/DA* lens lineup inhibits anyone's ability to make outstandingly good photographs in or out of the studio.
Again, I am not bagging on you. I'm just trying to better understand your issue(s) and maybe learn something in the process. And if I'm a colossal moron in my ignorance here then by all means direct the flaming projectiles my way.