I enrolled in the "Understanding Exposure" online class offered by the Perfect Picture School of Photography. The course ran for 8 weeks starting 9/21/2007. Each week, we were allowed to submit 3 photos for critique by Bryan F. Petersen, author of the book this course is named for. Another professional photographer, Chris Hurtt, ran the Q&A forum to answer the many questions posed by the 45 students. The course ended on 11/20; I submitted 25 photos in all.