Foil filter

Foil filters are made from various plastics or from gelatine . Usual dimensions are 75 × 75 mm and 100 × 100 mm.

Foil filters are offered in a wide variety, including color filters for black and white photography (red, orange, etc.), color correction filters (for fine-tuning the color temperature ) and infrared filters. They are comparatively inexpensive and, with good film filters, no effect on the image quality can be seen in practice.

To use them on the camera , you need a special filter film holder that should keep the film as flat as possible. In a compendium there is usually already a slot which is used to hold one or more foil filters.

The best (and most sensitive) are the Wratten filters from Kodak , which are made of gelatine with the appropriate colorants mixed in. The colorants do not always remain stable when exposed to light for a long time.