The Heliopan 37mm KB-18 Filter is a color conversion filter that helps to increase the color temperature from about 2600 to 5500K. This blue filter allows you to use daylight-balanced film in 40W tungsten lighting without any color casts due to the lighting.
There is a 4.5x filter factor with this filter, requiring an increase of 2.6 stops for normal exposure. It has a 37mm brass mounting ring that is painted a matte black to help reduce reflections. The SH-PMC multi-coated Schott glass provides greater contrast and reduced reflection compared to uncoated filters.
Color conversion filter brings color temperature from 2600 to 5500K for use with daylight film in tungsten lighting situations.
37mm brass mounting ring that is painted a matte black to help reduce reflections.
SH-PMC multi-coated Schott glass provides greater contrast and reduced reflection compared to uncoated filters.