Originally posted by christiandre according to you, is the use of K1 is relevant for this kind of practice ? with or without crop mode....
Definitely. You can use crop mode if you want, but other features are the viewfinder (so you can see when the bird will enter the frame and get ready to take the shot), more photo data (so you can push the PP on photo without losing quality), the tilting screen so you can use tripods more comfortably, shoot without facing the animal (which can scare them).. probably the AF will be really great, as well. Burst mode speed seems decent, too.
Originally posted by christiandre Does the loss of focus would be offset by other advantages, compared with an APS-C ?
"loss of focus"? I don't know what you mean by that. Depth of field? Sure, on FF mode the DoF will appear more shallow, but if you shoot around f8 that probably won't be an issue. And you can still select APSC mode to get everything that APSC offers. The main advantage of APSC is that it is a smaller, lighter camera - which can be a big factor on hikes - and that FF cropped to APSC has lower resolution than native APSC cameras (so you get full resolution at the APSC magnification). And of course price, as APSC is more affordable. But looking at image quality, the FF should be at least as good as the K-3II, but most likely it will be better. Less digital noise, more dynamic range. These might not be significant in everyday low-ISO photos, but it might become significant if you do a lot of PP or if you shoot in poor light conditions.
Originally posted by christiandre maybe with a 150-450mm i could expect similar shots (~400/450mm) with a gain in terms of quality : light transitions ISO etc... ?
I think the 300mm should be fine on the FF camera. And that 150-450mm lens looks really great, as well. If the K-1 sells really well, other brands like Tamron and Sigma might put K-mount on more of their lenses (they make a couple telephoto zooms that don't come in K-mount right now).
Originally posted by Dr_who The camera will be available for some time, no need to rush and buy it on day one.
Yeah, I think we can wait for a review or two. Of course, many people have already pre-ordered it, and some will buy it quickly. I doubt it will be disappointing to anyone. The specs seem good, the sample photos look good, the camera itself looks pretty good..
Edit: I wasn't planning on getting the K-1, but looking at the specifications now.. it is very, very tempting.