Hi all! I have a Canon 550D (well mines branded kiss x4, since i got it out of the country but anyway) and i want to attempt one of those photos where you take a really long exposure of stars and they go around in little circles...
My question(s) are:
1. Can you attatch a external powersource to the 550D so it doesnt run out of juice?
2. Is there any special way of taking photos like that?
3. Would the internal battery last long enough to take a photo like that?

Thankyou!