If you choose not to use a flash, high-speed film is recommended to help eliminate the depth-of-field problem; however, you will have clearer detail with slower film. Select high-speed film, such as ASA 400 or ASA 1000, for color slides, and Tri-X pan for black-and-white prints. With flash photography, use slower, moderate speed film (ASA 25, 64, or 100) for color slides and Panatomic-X (ASA 32) or another fine-grained film for black- and-white prints.
How you adjust the lens opening and shutter speed to the available light determines whether your photograph will be dark and muddy or clear and beautiful. For close-up flash photography of most butterflies, set the lens at f/ 16 and the exposure time at 1/60th of a second, or the setting on your camera that indicates flash synchronization. When photographing white or very light-colored butterflies or blossoms, use 622. For shooting in natural light without a flash, take an exposure reading before each set of pictures. Set the lens opening as small as possible, with the exposure time fast enough to prevent blurring (usually no slower than 1/30th of a second). When photographing without flash in a deep forest with dense shade, try taking pictures with your high-speed film 11 pushed' to ASA 800 or even ASA 1000. Be sure to instruct the photo lab to develop these rolls accordingly.