Colored filters are useful in controlling the contrast in an image, where various contrasting colors are present in the specimen. If, for example, a specimen has faint red and blue areas, a red filter will make the blue areas dark and the red areas light. Conversely, a blue filter will reverse this contrast pattern. A set of five 2" square Interference Filters, Cat. No. 42-47-55-01, is available for use in Microscopy. These glass filters give relatively narrow pass bands and are more resistant to light and heat than the traditional gelatin filters.
To reduce light intensity, neutral density filters are available. These come in various densities and sizes. The 2" square set, Cat. No. 31-34-88-01, contains 4 neutral density filters and a daylight blue filter. The High Intensity Base Illuminator and the Professional Optilume have provision for the use of 2" round or square filters. The High Intensity Base Illuminator is equipped with a Flip-In 1.0 N.D. Filter.
Two color-balancing filters are available for use in Photomicrography. Cat. No. 31-35-86 is for use when using Daylight Type Color Film. Cat. No. 31-35-87 is for use with Tungsten Type Film.