What is the ISO?

ISO refers to your film ‘speed’ or its sensitivity to light. One easy way to remember how ISO works is that the lower the rating, the less sensitive your film is. It may also be referred to as a ‘slow’ film. Higher ISO films are often used during low light conditions since they are more sensitive to light. They are also referred to as ‘fast’ films.

Left: Babylon Kino B&W 35 mm ISO 13 by @davidalexandre, Right: Lomography Color Negative 35 mm ISO 100 by @negus
Left: Lomography Color Negative ISO 400 by @larahacefotos, Right: Lomography Color Negative ISO 800 by @akio_nakai

Low ISO films are great for sunny days since you’ll have more room to play around with your exposure. The image won’t look too blown and with the right settings and enough practice, you’ll be able to get correct exposures. Low ISO film also produces fine grain. When using low ISO films in low light you will need to use a tripod in order to use a longer shutter speed and get enough light in your shots.

Higher ISO films on the other hand are ideal for shooting in low light like indoors or at night. Grain is much more visible in high ISO films. High ISO film is also recommended for shooting moving subjects in order to minimise motion blur.

Experimenting with different ISO films and settings on your camera will allow you to make different effects in your shots.

Fun fact: The International Standard Organization introduced the ISO rating system for color film in 1979.

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