filter color use colorless UV(0) none absorbs UV 0 clear thickness compensation 1 absorbs UV < 360nm 1A pale pnk skylight filter 1B lt. pink (skylight) cuts blue cast in shade and distance, absorbs UV yellows 2A pale yel UV 405 nm 2B pl yel absorbs UV 390 nm 2E pl yel absorbs UV 3 lt yel 4 lt yel CCC - corrects outdoor scenes for panchromatic film 6 lt yel (aka K1) partial correction for outdoors 8 yel (aka K2) full correction outdoors for Type B panchromatic film 9 dp yel 11 yl-grn (aka X1) corrects tungsten light for Type B film 12 dp yel minus blue - haze cutting for aerial photography 13 yel-grn (aka X2) corrects tungsten light for Type C panchromatic film 15 dp yel (aka G) contrast control in aerial IR photography 16 yel-org blue absorbtion 18A transmits UV and IR only oranges and reds 21 org blue and blue-green absorbtion 22 dp org yellow-orange (mercury yellow) increase contrast in blue preparations for microscopy 23A lt red contrast effects 24 red for two-color photography 25 red (aka A) for tri-color separation, high contrast effect, aerial IR haze two-color general viewing 26 red stereo red 29 dp red high contrast, tungsten projection of tri-color, red sep. in fluor. process magentas and violets 30 green absorbtion 31 green absorbtion 32 magen minus green 33 strong green absorbtion 34A violet blue separation in fluorescence process 35 contrast in microscopy 36 dk violet blues and blue-greens 38 red absorbtion 38A Blue red absorbtion, increasing contrast in visual microscopy 39 contrast control in printing motion pictures 40 green two-color photography 44 lt blu-grn minus red, two-color general viewing 44A lt blu-grn minus red 45 contrast in microscopy 46 blue projection 47 blue direct color separation, tungsten tri-color projection 47A lt blue 47B dp blu tri-color separation form transparencies 48 green and red absorbtion 48A green and red absorbtion 49 dark blue 50 very dark blue - mercury violet greens 52 lt grn 53 middle green 54 very dark green 55 stereo green 56 very light green 57 green for two-color photography 57A lt grn 58 grn tri-color green for separations, contrast in photog & microscopy 59 green for tri-color projection 59A very light green 60 green for tungsten two-color photography 61 dp grn grn tri-color sep, tungsten projection 64 red absorbtion 65 red absorbtion 66 contrast effects in microscopy & medical photography 67A red absorbtion Two-color projection narrow band 70 dk red IR photography 676 nm 72B dk or-yel 605 nm 73 dk yel-grn 575 nm 74 dk grn mercury green 539 nm 75 dk blu-grn 488 nm 76 dk vio (compound filter) 449 nm Hg line filters 77 transmits 546 nm mercury line. glass plus gelatin 580 nm 77A transmits 546 nm mercury line. glass plus gelatin 582 nm photometrics 78 bluish photometric filter (visual) 78AA bluish photometric filter (visual) 78A bluish photometric filter (visual) 78B bluish photometric filter (visual) 78C bluish photometric filter (visual) 86 amber photometric filter (visual) 86A amber photometric filter (visual) 86B amber photometric filter (visual) 86C amber photometric filter (visual) light balancing 80A blue color correction for daylight film (5500) under 3200K (studio) lamps 80B blue color correction for daylight film (5500) under 3400K (photo) lamps 80C blue color cor. for daylight film (5500) under 3800K (clear flash) lamps 81 amber warming -100K 81A amber color correction for Type B tungsten film under 3400K (photo) lamps warming -200K 81B amber to remove blue cast in shaded daylight warming -300K 81C amber to remove blue cast in cloudy/rainy weather; Kodachrome Type A with flash; warming -400K 81D amber Kodachrome Type A with flash; warming -500K 81EF amber Ektachrome Type B with flash; warming -650K 82 blue cooling +100K 82A blue color correction for Type A tungsten film under 3200K (studio) lamps cooling +200K 82B blue color correction for Type B tungsten film under 2900K (100w incand.) cooling +300K 82C blue to remove reddish cast in early morning or late afternoon cooling +400K 83 amber 16mm commercial Kodachrome in daylight 85 orange color correction for Type A tungsten film in daylight (5500K->3400K) 85B orange color correction for Type B tungsten film in daylight (5500K->3200K) 85C amber converts 5500K (daylight) to 3800K lighting miscellaneous 79 photographic sensistometry 87 for infrared photography; absorbs visual 770nm -> 87C absorbs visual, transmits IR 830nm -> 88A for infrared photography; absorbs visual 740nm -> 89B for infrared photography 700nm -> 90 monochrome viewing (narrow-band for viewing scene brightness); about 570->590 nm; 10% luminous transmittance 96 neutral filter for controlling luminance; 9% luminous transmittance 97 dichroic absorption 102 correction filter for Barrier-layer cell 106 correction filter for S-4 type photocell FL-day purple converts daylight fluorescent light for daylight film FL-W purple converts white fluorescent light for daylight film K2 yellow improves contrast in B&W; absorbs UV and part of violet G orange greatly improves contrast in B&W; absorbs UV and part of blue-green 25A red strongest B&W contrast; absorbs UV and part of yellow; "night filter" also used as a color separation filter with #47 blue and #58 green X0 yel-grn natural rendition of skin and lips of female models B&W? X1 green Absorbs more red than X0, good for green trees B&W? Data on a very few narrower band filters: Filter no. low l high l domin. l lum. transm. Color separation filters: 47 blu 400 475 464 2.8 58 grn 490 600 540 23.7 25A red 590 700 615 14 Narrow band filters: 76 400 470 449 0.046 75 460 530 488 1.3 74 510 570 539 4.0 73 560 600 575 1.3 72B 590 640 605 0.74 70 660 700 676 0.31 This data is from the CRC handbook. Much more data is available in the CRC.