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Simon_5087
24-Jan-2005, 06:22
Hello,

Does anybody know of a site where you can correlate camera film with light source to find out what filter needs to be used to give an accurate portrayal of the colours recorded, such as photographing indoors under fluorescent light. Thank you.

Simon

Bob Salomon
24-Jan-2005, 07:50
It sounds like you need a Macbeth Color Checker and some film to test under the lighting conditions you plan to use. Any good camera store will have both.

Ralph Barker
24-Jan-2005, 07:56
The B+W filter section on the Schneider site (http://www.schneideroptics.com/filters/) provides information on individual filters, and you find retailer sites like B and H Photo (http://www.bhphotovideo.com/bnh/controller/home) also provide a fair amount of information. For really accurate color rendition, however, you'll probably need a color meter to check the actual color temperature of the lighting, along with a range of color correction (CC) filters.

Bob Salomon
24-Jan-2005, 10:40
"correlate camera film with light source to find out what filter needs to be used to give an accurate portrayal of the colours recorded"

Sorry for my earlier answer. I misread your question.

If you check with a source like http://www.digigo.com/color_temperature.htm (http://www.digigo.com/color_temperature.htm) you will find the mired value of many different light sources.
Film types also have a mired value which the film manufacturers will give you.

For color correction companies like Heliopan make decamired filters. The KR series are warming and the KB series are cooling filters. The sereis are additive. A KR 1.5 (skylight) and a KR 3 make a KR 4.5 filter. A KB 6 and a KB 1.5 make a KB 7.5.

As both light and film have mired values if you subtract one from the other and divide the difference by 10 you will know the decamired filter necessary to balance the light to the film.

Otherwise you would use a 3-color color temperature meter.

Tim Hettinger
24-Jan-2005, 14:44
There was another great source that listed suggestions for different brands of bulbs, both fluorescent and amny other types, but I couldn't find it. maybe another google search will help you out. but here's a start for you. These are suggestions and you should test with your films and filters before critical work. and a color temperature meter would be nice.
good luck


http://www.geocities.com/thombell/nontrad.html (http://www.geocities.com/thombell/nontrad.html)

Kirk Gittings
25-Jan-2005, 00:05
Unfortunately as an architectural photographer I have tried allot of such filter recommendations for flourescents and transparencies over the years and found them all way off the mark. There are too many variables, cool white, warm white, daylight, super savers etc etc. ,plastic coverings etc etc, colored carpets the lights bounce off of etc. etc. . If you are serious about shooting chromes under flourescents you have to have a color temp. meter and a ton of gelatin or polyester filters because you always need two and sometimes three. There is no way around the meter and lots of filters except trial and error. Except.....

Having said that most arch photographers use a forgiving film like Velvia 100f and strobe fill. This works especially well in mixed light situations. With this you can virtually forget about the need for filters. Some modern films are very forgiving with strobe fill and flourescent ambient at a ratio that gives you about 1/2 second at f22 with strobe fill the flourescents usually go nuetral. EPN and Velvia 100F are two of the best.

But.....again the easiest solution is to shoot NPS or NPL negs forget about the filters and adjust color in the print or scan. When I am dealing with a room that is completely lit by flourescents, that is what I do. It works incredibly well.

What are you shooting?