My friend Sam Wang built a camera that uses 5X7 film to make circular negatives with the 50mm Mamiya Press lens and he did some beautiful work with it. His book that has just been published in China contains many circular images made with the 50m Mamiya lens and his home made camera. He has a show opening in a few days in Shanghai in conjunction with the publication of the book.
Originally Posted by 2F/2F
The 50mm Mamiya lens is a great lens, almost distortion free and sharp. But use a lens hood with it as flare can be a problem.