My wife has a DSLR. My daughter has a non-SLR digital camera. When you press the shutter on the DSLR it behaves pretty much as a film SLR, that is, there's a click and the picture is taken immediately. When you press the shutter on the non-SLR there is a noticeable delay before you get any feedback that the picture has been taken. I've noticed this same behavior with other digital cameras. What's happening?