Originally posted by pingflood Not picking on you in particular, but why is it that so often people blurt out "Well go buy a Canikon" rather than agree that some things could be improved, and maybe if enough people make an issue out of it Pentax will listen to them?
When there is a real problem, and I could perhaps quote lens QC and HSS flash exposure as being 2 current issues, then I think its worth doing something about it. Whether moaning on public forums works I would doubt. I prefer constructive dialogue personally. The engineers know exactly how their specs match the competition, and they have the means to test it.
When the OP is claiming that the D300 is "perfect" then the most obvious conclusion is that he bought the wrong camera or he is a Nikon troll or that he does not have a clue what he's on about.
I dont know any camera that can reach its maximum quoted frame rate in AFC mode. With a fast subject, the D300 manages about 4fps with a good lens, which is a very fair performance. Canons are a bit faster on the whole (fewer focus points) but only when tracking near the centre frame.
When you think about it the reason is fairly obvious. The mirror has to be down long enough for the AF sensor to re-acquire the moving target, then calculate the refocus distance, then move the lens before firing the shutter fire again.
At 5FPS you have precisely 0.2 of a second for all that to happen, minus the blackout time (time for the actual exposure + the mirror return speed).
Now the blackout time is what actually dictates the FPS rate in the first place, so you are expecting the camera to effectively do the whole refocus job instantaneously.
Even refocusing a DA* lens in less than 0.2 seconds is a BIG ask. Doing it in zero time is pretty much impossible. If nikon and canon are faster, its simply because some of their lenses move faster but I still dispute the fact they will achieve anything close to their maximum frame rate in AFC mode.
Like I said, I've nothing against real issues, only against ignorance leading the debate. Far too many people on camera forums start crusading against non-issues, often when they dont even have the camera, and often based on their own mistaken interpretation of numbers they dont understand, or testing that is flawed, or some rose tinted impression that the grass is several shades greener in Canikon land when its seldom clear cut.
Pentax AFC wont get much faster till they add ring motors. As it is, my FA* 300 F4.5 focuses faster than my 50-135. Do I care? If its accurate, no. Frankly nothing short of a D3 or 1D would do if you really needed that kind of performance.