The Konica-Minolta 62mm A12 Color Conversion Glass Filter is for using tungsten film in daylight. A #85 filter will decrease the color temperature from 5500K to 3400K and produce slightly cooler results than an 85B.
What do you do when you must take some photos outdoors and all you have left is tungsten film? Using tungsten film in daylight will produce a bluish cast in the photograph. The 85 series of filters will "bring back", i.e. color balance the tones in your images. These yellow filters are used to correct differences in color temperature between the recording medium (film/video) and the light source.
It should be noted that an 85 filter produces slightly cooler results than an 85B (with tungsten film in daylight) whereas an 85B converts tungsten film to daylight. The 85C produces the coolest results - more than either the 85 or 85B. However, it is interesting to remember that an 85C is also useful as a creative warming filter with daylight film in daylight.
Note: Whereas the 85 series is used for tungsten film under daylight conditions, use the 80 series of filters when using daylight film under tungsten lighting
85 Series Color Conversion Chart
- An 85 decreases the color temperature from 5500-3400 Kelvin
- An 85A decreases the color temperature from 5500-3100 Kelvin
- An 85B decreases the color temperature from 5500-3200 Kelvin
- An 85C decreases the color temperature from 5500-3800 Kelvin