The 81 Series of filters controls the bluish coloration that can affect daylight film. They warm scenes shot on cloudy days. They can also remove excessive blue from the effects of electronic flash. These filters are also good for general scenics when the photographer wishes to remove the bluish cast from open shade or just add warmth to the photograph. The 81 series is available in grades from 81 through 81EF, with 81EF having the warmest effect.
The 82 series are light balancing filters used to increase the color temperature slightly for a cooler tone. This light blue filter absorbs the excessive yellow-red light from daylight in the morning and evening hours and keeps skin tones close to natural.
The filters in this kit measure 4 x 4" (100 x 100mm).
This kit includes the following filters:
81A decreases color temperature 200 degrees Kelvin
81D decreases color temperature 500 degrees Kelvin
82A increases color temperature 200 degrees Kelvin
82C increases color temperature 400 degrees Kelvin