KODAK Safelight Filters are available in sizes to fit the KODAK Safelight Lamps. Their transmission characteristics make them suitable for use with a number of photographic materials (see the Safelight Recommendations table).
Blue-Sensitive and Orthochromatic Black-and-White Films
You can handle these types of films under red safelights. The spectral sensitivity and the speed of the particular film determine the safelight filter that you need. See the Safelight Recommendations table.
Black-and-White papers are developed in processors or by inspection trays. Safelight illumination is generally brighter near the trays than it is anywhere else in the darkroom. Be sure that this illumination is safe for the total development time. Excessive exposure to proper safelight illumination, or normal exposure to unsafe illumination, will degrade the highlights and lower print contrast. This occurs before actual fogging is visible in areas that receive no white-light exposure, such as print borders. As a result, a questionable safelight condition might not be detected for some time. (See Test for Black-and-White Papers.)
Safelight exposure can occur before and after the printing exposure. A low-level overall exposure either before or after the printing exposure is technically referred to as a "super-additive exposure." "Safe time" for safelight exposure is defined as any exposure time less than or equal to one-half the time required for a safelight to produce a detectable change in a particular sensitized product. Virtually all exposures are cumulative and can cause contrast and density changes. Test for Black-and-White Papers and Test for Other Photographic Materials will help you determine a safe time for your application.
Panchromatic papers are more sensitive to the safelight illumination normally used with black-and-white papers. To help protect these papers against image-quality change and safelight fog, use them with special filters or small-wattage bulbs (see the Safelight Recommendations table). Safelight specifications are printed on the package. Recommendations for safelight filters for specific Kodak photographic materials are based on test procedures similar to those described in ANSI Standard PH2.22-1998.
Handle color camera films, duplicating films, internegative films, slide and print films (for making transparencies from color negatives), and KODAK PROFESSIONAL and KODAK EKTACHROME Papers and Materials (for making prints directly from slides and tranparencies) in total darkness.
Also handle papers and materials for Process RA-4 in total darkness. These materials include KODAK PROFESSIONAL Papers and KODAK EKTACOLOR Papers, as well as KODAK PROFESSIONAL DURAFLEX Print Material, KODAK PROFESSIONAL DURATRANS Display Material, and KODAK PROFESSIONAL DURACLEAR Display Material.
However, if absolutely necessary, you can use a safelight equipped with a KODAK 13 Safelight Filter (amber) and a 7½-watt bulb. Keep the safelight at least 4 feet (1.2 metres) from the paper. Run test to determine that safelight use gives acceptable results for your application. Using a safelight will affect your results.
2Data in this column refer only to use of the KODAK Utility Safelight Lamp, Model D.
3Requires reduced bulb wattage.
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