Originally posted by pingflood Now go grab a D300 and a K20D and go do some actual shooting and see which one performs better.
Honestly, I find it hard to believe that people claiming the K20D is as fast as or faster than the current prosumer cameras from the competition have ever shot with them. You can keep picking tests or setups that'll show an advantage, but in the end photography is done in the real world and that's where the true performance shows. The K20D is a very good, no a GREAT camera, but it doesn't smoke the competition in every area. You can keep trying to prove it does, or keep deluding yourself into believing so, but from somebody who's shot and handled a multitude of bodies going from ancient Leicas to viewcameras to current pro gear, IT AIN'T SO. Believe me, I didn't want to spend thousands more to get what I really wanted in a camera, but the difference was significant enough that I couldn't ignore it.
Funny thing about the AF speed comparison between Pentax and the other brands. It seems to me to be largely lens dependent as I can take Pentax's D FA100mm f/2.8 macro and measure it's AF speed with a calendar when compared with the 100mm f/2.8 Macro from Canon and Sony. Oddly the Nikon 105VR seems a bit slower than Canon and Sony, but still much faster than the Pentax. However if you take the DA* 55mm f/1.4 and compare it to the Nikon 50mm f/1.4G, the Canon EF 50mm f/1.4USM and the Sony 50mm f/1.4, there is not a person on the planet who can prove to me that one of these lenses focuses appreciably faster than another.
To me, the lenses that make the AF shine in the other brands mostly shows up in the lens types where Pentax does not participate. The Sony 70-400G, Nikon 80-400VR and Canon EF 100-400L just don't have a Pentax equivalent. I rather quickly condede the focusing speed advantage on these and a number of other lenses where Pentax is slower (above mentioned macro, DA 18-250 and the DA 17-70). However I have convinced many folks, many more than have subsequently jumped on the Pentax bandwagon but convinced nonetheless, that Pentax stacks up very nicely against the other brands as we walk around the grounds of the mall where the store sits.
The long and the short of things is some folks will be disappointed with Pentax's AF, but ironically it is the real world shooting where the difference between Pentax and the others becomes rather small. Think also of the other benefits inherent to the Pentax system. How much do Canon and Nikon charge for their IS or VR 50mm lenses? How much do they charge for their glorious rendering 50-135 lenses?