Originally posted by Ole The sole purpose of optical preview is to check depth of field at the shooting aperture. I.e. verify that those objects you want sharp actually are sharp.
It is, however, very difficult to judge the effect and the useability is limited.
yeah even on a film slr, I've found it to me a bit more of an interpretation than a tool telling you yeah or nay. Most of the time I've just ended up feeling like I wasted my time with it. However with digital if it is important to actually check I'd just as soon shoot a shot and check it, even if it writes to the card. I guess I'll have to open up my 10d box soon and start playing I got it 3 days ago but have been too busy to open it and do it justice. I have been debating about wrapping it and putting it under the tree, even though most of the savings used came from birthday money, and I pre-ordered round about my birthday.