Kodak Color Compensating Filters Specifications & Spectral Data

Kodak color compensating filters are frequently used to fine-tune the color balance of tungsten-halogen microscope light sources for photomicrography with color films. These gelatin filters control color by absorbing different amounts of the red, green and blue parts of the visible light spectrum. Use the links below to navigate to pages containing specifications and spectral data for color compensating filter sets.

• Red CC Filters

  Red color compensating filters have principal absorption maxima at 360 (ultraviolet), 450 (blue) and 550 (green) nanometers, and display minimum absorption in the red (620 to 700 nanometers) visible light region.

• Green CC Filters

  Green color compensating filters have principal absorption maxima at 340 (ultraviolet), 430 (blue) and 700 (red) nanometers, and display minimum absorption in the green (500-570 nanometers) visible light region.

• Blue CC Filters

  Blue color compensating filters have principal absorption maxima at 350 (ultraviolet), 550 (green) and 700 (red) nanometers, and display minimum absorption in the blue (390 to 470 nanometers) visible light region.

• Cyan CC Filters

  Cyan color compensating filters have principal absorption maxima at 340 (ultraviolet), 630 (yellow-red) and 680 (red) nanometers, and display minimum absorption in the blue-green (380 to 560 nanometers) visible light region.

• Magenta CC Filters

  Magenta color compensating filters have principal absorption maxima at 375 (ultraviolet) and 550 (green) nanometers, and display minimum absorption in the blue and red (620 to 700 nanometers) visible light region.

• Yellow CC Filters

  Yellow color compensating filters have principal absorption maxima at 420 (blue) nanometers, and display minimum absorption in the blue-green-red (500 to 700 nanometers) visible light region.

Color compensating filters are labeled with a number to indicate their ability to absorb light. The most common densities are 05, 10, 20, 30, 40, and 50, in which larger numbers denote denser (darker) filters. A typical filter designation code is given as:

CC50Y

where

CC = color compensating filter
50 = filter nominal peak density
Y = filter color (Yellow)

The blue region of the spectrum is between 400 and 500nm. The green region is between 500 and 600nm, and the red region is between 600 and 700nm.

Determining the density of a color compensating filter first requires measuring the filter's density with respect to its complimentary color. For example, a red color compensating filter has a low density to red light but a higher density to blue and green light (which combine to form cyan, the complimentary color of red). To determine the density, measure the density of the filter to its own color of light (red light to a CC Red filter). In this example let us assume that red = 0.02. Next, measure the filter density to blue and green light (again, in this example assume green = 0.07 and blue = 0.08). The average of the green and blue readings is:

(0.7 + 0.8)/2 = 0.75

After the neutral density (filter's density to color of its own light) has been subtracted:

0.75 - 0.02 = 0.55

The remainder is 0.055, which is very close to the 0.05 value indicated for the CC05R filter.