what are the dimensions it should be to qualify?
What are these pics for? - a art competition, an agency, a spot in a uni program? From my experience, friends that have gone into photography usually have a 11x14 portfolio/folder/book then have pictures from 8x10 to 11x14 in them. But as Janice has stated, I'd look into the requirments just to be on the safe side.
You've got to look up the university/college requirements. Or if you are nice to me, you can run upstairs and I will look through my books and tell you. Anyways I've got the poster board you need.
