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Old January 6th, 2011, 05:20 PM   #1
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Color Correction

I am getting ready to shoot an office scene. Two actors, no daylight present. Only flourescent lighting. I have a Pana HMC80 and Flolights 512 LED. The LEDs are daylight 5600 and I need them to light the actors. What gels (Lee filters) do I need to color correct the LEDs for flourescents? I don't have enough lighting to turn off the flourescents and use only daylight LED. So I need to match the LED to the fourescent. Thanks.
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Old January 6th, 2011, 07:40 PM   #2
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Originally Posted by Randy Lintecum View Post
I don't have enough lighting to turn off the flourescents and use only daylight LED. So I need to match the LED to the fourescent.
Impossible. There is no one fluorescent light spectrum -- what would you match to? And if you did manage to map your lights to the sickly green of cheap big-box store fluorescents, you probably wouldn't like the results.

Easiest way out is to relamp the fluorescent fixtures with lamps you know. For example, with the cinema lamps from Osram or GE. They make them in the "standard" bi-pin tubes used by most ceiling fixtures, and in most standard lengths. That way you bring the fluorescents up to 5600K or thereabouts, with a CRI of 90+ which should be a reasonable match to your LEDs. And should be a much nicer light to use for filming.
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Old January 7th, 2011, 04:12 AM   #3
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What you'd really depends on the florescent lamps. Most times I'm in that situation I've been working at the tungsten end of the spectrum and our UK fluorescents mostly tend to be warm white. Shooting film I've matched the tungsten lights using the appropriate grade CTB gel and plus green gel and used a magenta filter on the film camera.

Video cameras are more blind to the green (although some of the digital cinema cameras have a larger colour space), so you can usually get away without using the green gel. You really need to know the lamps in the room, but if you don't take a range of CTO grades to find the correct match on the day.
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Old January 7th, 2011, 05:34 AM   #4
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I'm with Bruce on this one, swap out the fluorescent tubes.
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Old January 7th, 2011, 11:33 PM   #5
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Swapping out the tubes may not be practical, depending upon how many there are. It certainly isn't the "easiest" solution, and it's probably the most expensive as well.

You do need to figure out the color of the existing tubes. You do this by finding the maintenance guy and looking at the box they came from, or just getting the make and model from the tube and Googling it.

If they're typical office fluoros, they're about 4100K, more or less. To balance your daylight LEDs to that you will need Rosco Cinegel #3408 CTO or better yet, Cinegel #3442 Straw to warm the LED light, and note that all fluorescent bulbs have a high amount of green in them too. In order to completely balance your Daylight LEDs to the fluorescents, you should also think about adding Cinegel #3304 Plusgreen as well. I'd buy one sheet of each and play with them on the set in various combinations.

This advice is taken directly from an email I received from Rosco when I asked them virtually the same question. To make your own combinations, check out

Rosco US : Filters : Cinegel

Really, this is neither Rocket Science nor a Black Art. It's simple math. The colors don't have to exactly match, just get close. And it matters not how nasty the eventual color may be; that's what White Balance is for.
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Old January 8th, 2011, 07:10 AM   #6
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The good news for me is, I'm not only into videography, but I also manage a mall and the staff that goes with it. We recently changed a lot of the flourescent light fixtures from the standard 4100k that Adam was talking about to a 6500k bulb that was listed as "Daylight". It actually changes the color. You may look into doing that. I'm sure they also make something closer to 5600k, if not exactly that.
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Old January 8th, 2011, 01:25 PM   #7
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Um, yeah, I think that's what posts #2 and #4 were talking about. But there are downsides, which I listed in my previous post. We can't possibly know if this is viable until Randy comes back and tells us how many tubes he'd be dealing with.

Plus, there are other considerations. Daylight Fluoros are anywhere from 3 to 20 times more expensive than regular garden variety tubes. Not a big deal if there are only a few tubes to swap out, but it can add up if you've got to do an entire office. And Daylights put out about a third less light than regular tubes, because they lack that nasty green spike that provides so much of the visible light spectrum (this is easy enough to test, and I have).

Of course, gelling his Flolights fixture will also reduce the light from that device by roughly the same amount.

I've got nothing against swapping out the tubes, and I've done so personally many times, but he asked about gels and I'm trying to answer the original question and keep things as simple and economical as possible. If it's only four tubes, then yes, $12 in tubes is cheaper and simpler than $20 in gel sheets.
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Old January 8th, 2011, 02:22 PM   #8
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Message deleted. I'll let Adam take it from here since he seems to have a handle on things.
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Old January 8th, 2011, 05:16 PM   #9
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Thanks to all of you! The dialogue and suggestions were exactly what I needed. I will check on how many tubes there are and see if I can find out what they are. Will look into swaping them out. I can also order the Rosco's as well. This is my first time with fluoror's and I don't want to have tell the actors that I botched the color so we have to go another day. I will try out these solutions ahead of time.

Thanks again.
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Old January 9th, 2011, 03:21 AM   #10
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They're more of a problem with film than video.
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