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Getting even cool white out of existing fluorescent fixtures


Tyler Clark

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So I have a job coming up and want to utilize the existing overhead flourescents.

 

I've always had problems with color cast making my skintones look gross no matter what I color balanced too and how much I pulled in the grade.

 

Whats the best way to utilize these fixtures and get a nice cool white look and not mess up my skintones.

Edited by Tyler Clark
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The other option would be to use +green on all your own lamps to bring them in the same range as the overheads (assuming they're all similar in correction needed) and then use an FLB filter on the camera. Apparently, such things are shamanistic knowledge these days, but were quite common in the film era.

You'll need a color meter, or someone with a color meter to look at the location and let you know the degree you need.

The other option is to use minus green on the exiting fixtures-- however that may not be possible depending on the fixture.

You can also buy the higher CRI Phillips tubes (Chroma or something like that?) and swap them out.

Any tube with a CRI over 90 would be ok.

 

Kinda all depends on the budgets of money and time you're working with.

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Let me preface my reply by mentioning that I am not an end user I am a manufacturer so all my information is based on theory not real world practice.

 

Your problem is not colour balance - it is the amount of the visible spectrum that is present in the light from the fluorescents referred to as CRI (Colour Rendering Index) or TLCI )Television Lighting Consistency Index). Lighting for image capture needs a CRI of 90 or above and/or a TLCI of 85 and above. This means that you should not need to do anything in post.

 

Retail and domestic lighting can have as little 70% of the visible spectrum (CRI 70) and this is why it is not suitable for image capture. The human eye is very sensitive to green and so lamp manufacturers often increase the green spectrum as that makes the light source appear brighter.

However the camera simply records what it sees and will notice the higher green content of the light.

This is what causes skin tones to look bad - no one likes to be slightly green.

 

In my opinion adding +green to your other fixtures will simply make this worse.

You could add -Green to the fluorescents but if you want them in shot this is not an option.

 

Swapping them out for broadcast quality tubes is the answer - not only Kino but GE Cinema+ or Osram Lumilux Deluxe would be suitable.

 

Regards

 

Pete

 

 

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In my opinion adding +green to your other fixtures will simply make this worse.

 

 

I think you missed the bit about using a correction filter on the camera.

The idea is to make all the fixtures match and then correct for this with the FLB filter.

Replacing the nasty flo's with high CRI tubes would be ideal but this isn't always an option.

 

Freya

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Exactly, you +green everything then remove it with a singular filter on the camera. This is best for, say, if you're shooting in a supermarket and just bringing in a few of your own lights-- such as Kinos-- which can be quickly +'d -v- swapping out every visible tube which really is only an option on the larger budgeted things which can afford the time/manpower.

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I'm confused by the question -- you want a cool white look (i.e. cyan-ish light on faces) but you want nice, normal skin tones? Isn't it one or the other?

 

Normal skintones is what Im looking for. Not coolish blue light. My bad.

 

It seems that skin tone quality though cant get much better without re-bulbing existing fixtures.

 

From what I gather from all the answers here it seems to be the best option to role with...

 

...Color Meter

...balance to the meter

...+green on production lights to match the meter

...pull green in post

 

Yeah?

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Depends on the camera and the recording codec -- if you are recording in an 8-bit Rec.709 codec, you may want to consider some degree of CC Magenta filter or a FL-B over the lens to pull some of the green out in the original, then finish to taste in post color-correction. But in theory, yes, match the amount of green on everything then either white-balance in camera, if possible, or pull green in post.

 

It gets harder to fix in post with blonde haired actors I've found because the amount of green in their skin looks different than the amount of green in their hair, so usually you settle on getting the skin to look correct.

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