rodmeister
Enlightened
Some ideas on fixing the greenish LS beam tint. These ideas came to me while responding to a thread on the LED CandlePower Forum.
CP FILTER: I attached a .05 density Magenta Color Printing (CP) filter by cutting it to diameter and using my Mini-Maglite Filter Holder. My filter set, a set of 3" square acetate filters in the subtractive primary colors: Cyan, Magenta and Yellow in varying densities, was manufactured by Ilford Cibachrome for color photographic printing, and other sets by other manufacturers are similar (about $40 per set.) I played around with different densities, colors and color combinations to find the best color which was .05 Magenta on my particular LS. The .05 Magenta cuts the output by about 5%. Since the corona is greenish and the central spot bluish, when I cancelled the green corona, the central spot became slightly magenta, a more pleasant color. A better solution might be cutting a hole in the center, leaving the magenta "donut" to cancel the green corona.
CC FILTERS: A more permanent solution would be to replace the flimsy and inherently scratchable CP filter with a glass CC (color compensating) filter in whatever color worked best on your LS using the CP filter set. The LS lens width appears to be about 18mm, which might be hard or impossible to find, so you'd need to buy the smallest CC filter you can find and have it cut to size by Lenscrafters. Glass CC filters cost about $35 to $100, manufactured by Tiffen, B+W, Hoya, and others - hard plastic filters are available from Cokin.
OPTICAL CEMENT: It might be possible to have Lenscrafter or other optical shop cement the glass CC filter directly onto the LS lens using transparent optical cement. Also try cutting a hole in the center.
ARC CC SOLUTION: ARC could buy the proper CC filters in bulk and correct the color problem at the factory. I'm not sure CC filters are durable enough to serve as the lens, though. ARC could sandwich a CC filter on the inside of their present lens. A donut shaped filter could be sandwiched if costs allow.
ARC REFLECTOR COATING: A factory, clear magenta coating sprayed on the reflector. The bluish white central beam would be unaffected but the green corona would be cancelled.
ARC LENS COATING: Factory coat the inside of the lens with magenta. A gradient spray pattern would only affect the green corona.
The factory solutions would add to the already high cost of the LS, and the owner enabled solutions are almost prohibitive...but maybe not for the hard-core flashaholic. And they all cut down light output.
P.S. "Mahoney" on the LED CandlePower Forum suggested using plastic gels designed for studio lights, which is much cheaper. Though gels and CP filters might create Newton Rings in the beam.
CP FILTER: I attached a .05 density Magenta Color Printing (CP) filter by cutting it to diameter and using my Mini-Maglite Filter Holder. My filter set, a set of 3" square acetate filters in the subtractive primary colors: Cyan, Magenta and Yellow in varying densities, was manufactured by Ilford Cibachrome for color photographic printing, and other sets by other manufacturers are similar (about $40 per set.) I played around with different densities, colors and color combinations to find the best color which was .05 Magenta on my particular LS. The .05 Magenta cuts the output by about 5%. Since the corona is greenish and the central spot bluish, when I cancelled the green corona, the central spot became slightly magenta, a more pleasant color. A better solution might be cutting a hole in the center, leaving the magenta "donut" to cancel the green corona.
CC FILTERS: A more permanent solution would be to replace the flimsy and inherently scratchable CP filter with a glass CC (color compensating) filter in whatever color worked best on your LS using the CP filter set. The LS lens width appears to be about 18mm, which might be hard or impossible to find, so you'd need to buy the smallest CC filter you can find and have it cut to size by Lenscrafters. Glass CC filters cost about $35 to $100, manufactured by Tiffen, B+W, Hoya, and others - hard plastic filters are available from Cokin.
OPTICAL CEMENT: It might be possible to have Lenscrafter or other optical shop cement the glass CC filter directly onto the LS lens using transparent optical cement. Also try cutting a hole in the center.
ARC CC SOLUTION: ARC could buy the proper CC filters in bulk and correct the color problem at the factory. I'm not sure CC filters are durable enough to serve as the lens, though. ARC could sandwich a CC filter on the inside of their present lens. A donut shaped filter could be sandwiched if costs allow.
ARC REFLECTOR COATING: A factory, clear magenta coating sprayed on the reflector. The bluish white central beam would be unaffected but the green corona would be cancelled.
ARC LENS COATING: Factory coat the inside of the lens with magenta. A gradient spray pattern would only affect the green corona.
The factory solutions would add to the already high cost of the LS, and the owner enabled solutions are almost prohibitive...but maybe not for the hard-core flashaholic. And they all cut down light output.
P.S. "Mahoney" on the LED CandlePower Forum suggested using plastic gels designed for studio lights, which is much cheaper. Though gels and CP filters might create Newton Rings in the beam.
