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 filters in this kit measure 4 x 4" (100 x 100mm).
This kit includes the following filters:
81 decreases color temperature 100 degrees Kelvin
81B decreases color temperature 300 degrees Kelvin
81D decreases color temperature 500 degrees Kelvin
85C decreases the color temperature from 5500-3800 degrees Kelvin