Believe it or not - the same rules apply. Find out the "projector's" resolution and you have your answer - many top out at 1024x768.

A few more professional versions (usually meaning ovr $1000) will be 1280x1024 or higher. Spend a few grand and you'll find most top out at 1920x1080 which is full-blown HD video - yes, the highest res HD is really that small.

And no - they're pretty faithful to the digital image - nothing breaks up because it's being projected so they should look just fine when sized right.

Hope that helps-
-Lew ;-)