SLOW MEDIUM FAST
6, 25, 32, 50, 64 100, 125, 160, 200 400, 800, 1000, 1600, 3200 (less sensitive to light) (more sensitive to light)
Setting the ASA/ISO on your camera programs the sensitivity of your light meter.
Considerations when choosing film: AVAILIBLE LIGHT
SIZE OF FINAL PRINT
The amount of light usually dictates what film to use with low lighting requiring faster films. Abundance of light provides the opportunity to use fast or slow films.
To capture movement (freeze the action) faster films provide greater possibilities. To blur out the movement on purpose requires slower films and tripod, however, either option can be accomplished by both slow and fast films depending on the amount of light.
The amount of grain and visibility of detail is impacted by the speed of film selection. Faster or higher speed films create more grain, while slow film reduces grain.
Slower films enable one to show greater detail in their images, while faster films can hinder the ability to see detail. The size of the image dictates the amount of visible grain affecting images clarity.