One big reason to go FF is depth of field. DOF is a function of aperture, focus distance, and focal length. To get the same framing with an APS camerayou're always going to be using shorter focal lengths. So even if you're using the same aperture and the same focus distance to frame the same shot, the fact that the APS camera is using a shorter focal length means you're always going to have greater DOF, meaning less background blur, less subject "pop". So if you like isolating your subjects from busy backgrounds by using shallow DOF, a FF camera will always do a better job of it than an APS camera.I stand corrected. You are 110% correct. The 10-22 does have betterNo, it does not make sense. You can design a 3 mm lens for a P&S withMy next camera will be full frame. While you can get Ultra wide lens
for 1.6x crop, you end up with lots of distortion compared to a full
frame lens. It just makes sense that you can design a 17mm lens with
less distortion than a 10mm lens.
little distortion, too, as long as there is market for it.
In fact, the 10-22 distorts less at 10 mm that the 17-40 or the 16-35
at their widest ends (see photozone). The distortion at 10 mm is not
worse than that of a standard zoom.
The real difference is that with FF you can use UWA primes that Canon
would not make for a crop sensor.
distortion control. Wow, maybe there really isn't many reasons to go
full frame LOL
If you want to see the difference, look here and scroll down to the 5D MKII (FF) vs 500D (APS) side by side capture comparison of the street scene (image of the guy with glasses wearing a brown scarf). If you roll over the image with your mouse, you can compare the DOF from FF vs APS. You can see that the scene has much better background blur with the FF camera than the APS camera:
http://www.robgalbraith.com/bins/multi_page.asp?cid=7-9973-9976
As the article states: "A shallow focus effect can definitely be achieved with the Rebel T1i, but the 5D Mark II's larger sensor - and resulting longer focal length for a given field of view - allows for shallow focus that is, well, shallower. How apparent or significant this is depends on what you're trying to record, but in the one comparison we've done, the difference was dramatic."
It should also be noted that the FF shot was done at f/4, while the APS shot was done at f/2.8. And in spite of the FF shot being done at a slower aperture, it still produced better background blur than the APS shot.