For available light photography, there are no limits to what type of films or their speeds that you can use. Again, it is up to the type of equipment you have. For example, if you have a combination of fast lenses like the EF 28mm f/1.8 USM, EF 50mm f/1.4 USM and the EF 85mm f/1.8 USM, you can shoot with any colour negative or slides film having ISO 100 or lower. Of course, should you decided to shoot with ISO 200 or 400 films with the same fast lenses, the benefit is you can shoot available light pictures with greater depth-of-field rather than shooting at the lensesí maximum apertures. For nature photography, it depends on the situation. If it is about photographing birds using fast telephoto lenses like the EF 400mm f/2.8L II USM or the EF 600mm f/4L USM, you donít need to shoot with ISO 400 or higher speed films. The use of a monopod or tripod is recommended when using such lenses for bird photography. If you are photographing flowers or insects using macro lenses like the EF 100mm f/2.8 Macro, ISO 400 colour negative film is recommended if you need greater depth-of-field or shooting them without using strobes. If greater depth-of-field is not a concern, an ISO 100 film works just as fine. Film technology has improved tremendously over the years and today you can use ISO 400 film as your main film for all occasion even though the film manufacturers may recommend that the ISO 200 version is good for such purpose. With an ISO 400 film, you can shoot travel, people, sports, weddings, still life or available light with just one film. But that doesn't mean that you canít experiment with various other films to find the right colour balance or preferences to suit your taste. Over the next few pages EOS users can see photo galleries of subjects shot using ISO 100, 400 and 800 films. << Back to Main . 1 . 2 . 3 . 4 . 5 . 6 . 7 . 8 . 9 . 10 . 11 . 12 .