ISO-Choosing the Right Film
With several hundred different types of film on the market, which is the right one for you. Actually, that depends on why-and where-you'll be using it.
While film varies from brand to brand and type to type, one of the greatest misunderstandings about selecting the right film involves its ISO (formerly ASA)-a rating of a particular film's sensitivity to light. The higher the rating, the greater the film's sensitivity. Why worry about it? For one thing, taking good photographs in low light without flash requires more sensitive film. Taking photographs in bright light requires less sensitive film.
Also, the lower a film's ISO rating, the less "grainy" (or fuzzy) it generally appears, especially in enlargements. The higher a film's ISO rating, the more grainy it appears. As a good rule of thumb, use the lowest ISO rating suitable to your particular need. For example:
ISO 25-100. A good film for highly reflective bright-light situations such as at the beach, on a ski hill, or near water. Shooting a film with too high an ISO rating in exceptionally bright light (like 400 ISO or higher) may cause your shots to be overexposed.
A good general-purpose film for outdoors under relatively bright light, like in the back yard or at a ball game. If you're restricted to carrying only one type of film for a wide range of daylight photo situations, this is it.
ISO 400-1600. A good film for low-light indoor situations, outdoors at dawn or dusk, or anywhere in deep shadows. Also excellent from freezing fast action-from joggers to baseball players and from race cars to gymnasts.
So for the best photographic results you can get, start by using the right film for the job. The means selecting a film with the right ISO rating. The rest will be as easy as "Ready, aim, fire!"
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