Hi,
I want to sync a series of slides, which are projected by a projector with picture taking by a digital camera. Basically right now I am having a power point presentation with 12 slides and manually I load up each new slide, it is projected by the projector and than I take manually a picture of each projected slide. I am new to Arduino, but was wondering if there is a way? :-/ I saw that cameras get controlled by Arduino already.. Thank you very much in advance. 
If i understad you right, what you want is that Arduino should advance to the next PPT slide, then trigger a camera take a picture of the projected slide ?
Triggering the camera has been done by quite a few people, and i think you could use GoBetwino to send commands to the PC to simulate the keypress that advances to the next slide.
I havent tried this with GoBetwino, but i'm quite sure it is possible.
Wait - are these slides digital images, or are they photographic slides? If they are digital, they are already in a form in which it should be possible to get them as standalone images; if they are photographic, then why aren't you using a slide scanner (they aren't expensive like they were 10-15 years ago)...?
:-?
Thank you for your suggestions. I actually need to take pics of the projected slides, since I am projecting light patterns on an object. The taken pics will be utilized later by a software for a 3D scan. I think GoBetwino might be the way to go. Just found a motion detection software which might enable my camera to take pics once the light pattern changes....that would be an easy work around, since I have not done anything with Arduino before. :-?