OT

jkerry wrote on 6/12/2010, 3:54 PM
We built a small studio using 250 watt floresant lights with a 5600K rating.

The problem we are having is that the subjects have a green tint to them. There is no green in the studio. Black Background,

We have 2 lights on the fron of the subjects, one on each side and one from the back. Each of them have a sotl-light boxes.

Can sanyone offer some suggestions? I an at a lost now as to how to correct this problem.

Thanks,
Jeff

Comments

JJKizak wrote on 6/12/2010, 4:03 PM
Are you using video? film? what kind of cameras?
JJK
CClub wrote on 6/12/2010, 4:06 PM
Can you attach photo(s) to your reply?
PerroneFord wrote on 6/12/2010, 4:23 PM
More than likely a green spike from non color balanced fluorescent tubes. Replace them with some Kinos or something else meant for this kind of work. Or put some minus-green gel on them.

Common problem, easy solution.
musicvid10 wrote on 6/12/2010, 5:26 PM
You need full spectrum tubes with a CRI (Color Rendition Index) of 85 or better.
Color temperature alone doesn't tell the story with fluorescent tubes for photography.
Osram Studioline and GE Cinema are kind of the go-to products in this area (one or the other; don't mix the two on one set), and there are others including CF bulbs.
Gel filters and post correction are a last resort where you don't have control over the tubes. You do.
farss wrote on 6/12/2010, 6:11 PM
I'd also add that as the tubes age the green spike does diminish. Even the Osram Studioline tubes have a bit of a green spike out of the box.
If you want to get serious about matching all your light sources then you need a 3 sensor CT meter such as the Kenko KCM-3100. Cheaper units with only two sensors will give you the correct CT which as noted above is not enough data for you to compensate for the oddities of modern light sources with gells.

Bob.
musicvid10 wrote on 6/12/2010, 9:55 PM
Even the Osram Studioline tubes have a bit of a green spike out of the box.

That (along with the slight color temp difference) is why I cautioned not to mix with GE. The GE's were visibly pinker alongside, iirc.

That being said, every CC pro I have worked with prefers Osram for longevity, stability, and faithfulness to daylight conditions both with reflected and transparency media. Mind you this was all film, not digital experience on my part.

If this slight preference translates to digital still and video work, I don't know. Certainly seeing how well big-sensor camcorders white balance to them would give an indication. I guess it would be worth finding out which one Hollywood is buying these days.
farss wrote on 6/12/2010, 10:15 PM
We have heaps of lights that use the Osram 55W Studioline tubes. Really no problem with them and video at all. Kind of makes sense as they are designed specifically for video and TV studios down here are full of them.

The only time we've had some negative comment about them was a few years back from a stills guy shooting film, he did notice the green spike but he could grade it out.
Even HMIs drop CT with use. I believe on a big budget film shoot one task is to match all light sources using a good meter and gells.

Personally I've kind of given up loosing too much sleep over all this. If it's got color and it moves and it's in focus I and my clients are happy. If they want to pay enough to cover a few guys and a couple of grips trucks I'll rethink my position :)

Bob.