Aperture and Depth-Of-Field. In this fifth issue of The Art of Photography, EOS users and other photo enthusiasts alike can learn how to use one of the most important fundamentals in photography, the aperture, and its effects on pictures (Depth-of-Field) using their EOS AF 35mm SLR cameras. In the third issue of The Art of Photography, EOS users and other photo enthusiasts were shown how to use various focal lengths and angle-of-views of lenses in order to create better pictures using their EOS 35mm SLR cameras. In the fourth issue of The Art of Photography, they were shown how to make full use of shutter speeds to create better pictures with their 35mm SLR cameras. Understanding how to use shutter speeds effectively, is of course, just another part in the fundamentals of photography needed to create better pictures. One of the fundamentals of photography that is equally essential, after focal lengths and shutter speeds, is using the aperture to help you create better pictures. But just what is aperture? And why is it important in photography? Read on. << Back to Main . 1 . 2 . 3 . 4 . 5 . 6 . 7 . 8 . 9 . 10 . 11 .