Matching lights to existing light sources without a color meter

D

DDirector

Veteran
This was running through my head.

I was shooting in an office type of space and I needed to match my lighting fixture to the existing lights.
Typically it would be best to use a colour meter and use the light fixture to dial in the appropriate white balance and hue shift.

But, what if you have a light that's a fixed colour balance (5600K) and you do not have a light meter?


The only thought that is running through my head is preparing and planning this in advance, but not sure if this is the best method nor if it will work:
Using a white balance card get the reading for the white balance and the hue shift.

Knowing your light is 5600K, use the appropriate CTO or CTB gels to match or get as close as possible to the Kelvin the camera is telling you from the white balance.
Then as needed, apply green or magenta gels on top of that to balance the hue.

Not really something that I would try and figure out the day of, but I would have this written in a logbook so if I come across a situation where I need to match to a certain colour temperature & hue, I just check to see which gel(s) I need on the day.

It would be nice to have a variable colour light but it's not always possible - like if using the aperture lights
Do you think this would be the best idea and would it work?

__________
And what if the light has independent R, G, B channels?
How does one know how much of each value to use?
 
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DDirector said:
This was running through my head.

I was shooting in an office type of space and I needed to match my lighting fixture to the existing lights.
Typically it would be best to use a colour meter and use the light fixture to dial in the appropriate white balance and hue shift.

But, what if you have a light that's a fixed colour balance (5600K) and you do not have a light meter?


The only thought that is running through my head is preparing and planning this in advance, but not sure if this is the best method nor if it will work:
Using a white balance card get the reading for the white balance and the hue shift.

Knowing your light is 5600K, use the appropriate CTO or CTB gels to match or get as close as possible to the Kelvin the camera is telling you from the white balance.
Then as needed, apply green or magenta gels on top of that to balance the hue.

Not really something that I would try and figure out the day of, but I would have this written in a logbook so if I come across a situation where I need to match to a certain colour temperature & hue, I just check to see which gel(s) I need on the day.

It would be nice to have a variable colour light but it's not always possible - like if using the aperture lights
Do you think this would be the best idea and would it work?

__________
And what if the light has independent R, G, B channels?
How does one know how much of each value to use?
Click to expand...

Your method sounds fine. With +/- green, often small strengths like 1/8 make a significant difference. For example, you'll probably struggle to use 1/2 full plus green in most settings. In fact I've seen requests for a 1/16th strength which doesn't exist from LEE so a few strips of 1/8 were cut and placed over the light instead of the full filter. It should be easy enough to tweak on the day if you can't checking out the location ahead of time, particularly if your'e organised with the gels or better yet someone else is doing it.

You can also use a camera that lets you make hue adjustments, which won't match lights but should help if there are no other options.

I think most RGB lights now have separate colour correction functions. E.g. with the luxli timpani you can adjust tint (green/magenta) or apply a gel from the library, though I'm not 100% sure if there are +/- green gels because I've always done it in the tint screen.

If the RGB light doesn't have these other features I'd just dial it in by what looks good on camera.
 
I've always color balanced lights by eye. Also, I have a few single color temperature LED lights and I have precut gels ready to go in the kit. Like Rob said, 1/8 +/- green goes a long way. Usually too far.

My question is whether a color temp meter is an efficient way to set lights. I had the Sekonic C-700, but it seemed more like a fun hobby than a tool. The C-800 seems to have the ability to tell you if a light will match, but can it significantly speed up matching lights on set? I've found that most RBG panels don't actually match the exact color temperature they are reading on the settings, especially once they are diffused at all.
 
Welcome to the good ‘ole days! Even though it’s not really necessary now with a lot of LED’s I own, I still have my gel roll in the back of the truck and among other things, it contains CTO, CTB, +Green and -Green from 1/8 to Full. And I still keep a gel roll of color correction with my HMI’s.
 
Interesting. Thank you :)

In most situations, I dont think it would be necessary to match the lights so perfectly.
This isnt a feature or any big production. Usually some type of corporate work
So if the light is off by 1/16 of a +green, I'm sure that's not even noticeable.

Would having a light that has the RGB feature help with matching lights to ambient sources?
 
Honestly, in most places it's usually enough just with bi-color lights. My Gemini's and Hive's (and I believe my Astera's) can do +/- green as an individual adjustment and as a "gel", but I don't think I've ever used that function, yet. But it is very nice to have it there.
 
DDirector said:
Interesting. Thank you :)

In most situations, I dont think it would be necessary to match the lights so perfectly.
This isnt a feature or any big production. Usually some type of corporate work
So if the light is off by 1/16 of a +green, I'm sure that's not even noticeable.

Would having a light that has the RGB feature help with matching lights to ambient sources?
Click to expand...

The answer is yes and you'll find all sorts of ways to use RGB lights. At the same time I'd only buy an expensive light if:

- clients will see value in the purchase
- you can use it to add production value to your own shooting, which may get you more work or
- you think its features are worth it - no more gels, use an app for control while standing next to camera, be seen as a guy with expensive video equipment, can make money through rentals etc.

I don't know about softbox options but I think this would be a pretty solid corporate one man band set up - Luxli's latest light, the Taiko 2x1 - https://www.bhphotovideo.com/c/product/1479458-REG/luxli_orc_taiko_2x1_taiko_2x1_rgb_aw.html.

Another approach is to cut light e.g. office fluros around the immediate local area where the talent is being lit. You won't have matching colour across the board but depending on the existing ambient light, a difference in colour can make a bland office location more interesting. I'm sure many times back in the day people tried to disguise a completely blue exterior when using tungsten lights as a stylistic choice vs. constraints of a budget.

I should clear up a detail about the homemade 1/16th gel - I was doing lighting for someone and it was to "correct" an LED, not to match existing lights. Correct in parentheses because it was for an Area 48 and there is nothing wrong with that panel! Funnily enough I read a comment on one of the DP's other short films saying they thought the skin was too red/pink. Maybe he just prefers pink/sees more green than me!?
 
rob norton said:
The answer is yes and you'll find all sorts of ways to use RGB lights. At the same time I'd only buy an expensive light if:

- clients will see value in the purchase
- you can use it to add production value to your own shooting, which may get you more work or
- you think its features are worth it - no more gels, use an app for control while standing next to camera, be seen as a guy with expensive video equipment, can make money through rentals etc.

I don't know about softbox options but I think this would be a pretty solid corporate one man band set up - Luxli's latest light, the Taiko 2x1 - https://www.bhphotovideo.com/c/product/1479458-REG/luxli_orc_taiko_2x1_taiko_2x1_rgb_aw.html.

Another approach is to cut light e.g. office fluros around the immediate local area where the talent is being lit. You won't have matching colour across the board but depending on the existing ambient light, a difference in colour can make a bland office location more interesting. I'm sure many times back in the day people tried to disguise a completely blue exterior when using tungsten lights as a stylistic choice vs. constraints of a budget.

I should clear up a detail about the homemade 1/16th gel - I was doing lighting for someone and it was to "correct" an LED, not to match existing lights. Correct in parentheses because it was for an Area 48 and there is nothing wrong with that panel! Funnily enough I read a comment on one of the DP's other short films saying they thought the skin was too red/pink. Maybe he just prefers pink/sees more green than me!?
Click to expand...

My go-to "kit" for single person interviews now is a set of Gemini 1x1's(with one ~2'x3' Chimera and egg crate) and a set of Astera LightDrop's(8 light "briefcase" kit). The Gemini's are RGBWW and the Astera's are RGBW. You can do a lot with this. Probably at least as much as I could with two 1650's full of tungsten 10 years ago. And definitely a lot quicker and easier.
 
Run&Gun said:
My go-to "kit" for single person interviews now is a set of Gemini 1x1's(with one ~2'x3' Chimera and egg crate) and a set of Astera LightDrop's(8 light "briefcase" kit). The Gemini's are RGBWW and the Astera's are RGBW. You can do a lot with this. Probably at least as much as I could with two 1650's full of tungsten 10 years ago. And definitely a lot quicker and easier.
Click to expand...

That's a pretty awesome kit. The geminis look great but litepanels aren't popular at all here for whatever reason. I'd really like to pick up a pair of DMG Lumiere SL1s but they're still pretty far down the list.
 
no one has mentioned RGB scopes or histogram depending what camera you have.

You should be able to look at the practials (maybe boucing off a grey card) and see a channel sitting high (or not)

you then gel you film lights until they have the same hump - typically adding a bit of green or CTO

beter than doing by eye which self compensates

you may choose to cb off that grey card or shooting log film the grey card and do a colour balance in post.
 
agreed with Sam, although I'd generally rely on a vectorscope to do the same. Small/low resolution versions of scopes as one typically finds in a camera or onboard monitor tend to be a bit coarse for this type of thing. I use Scopebox software which allows you to scale up a given scope in size for more detail for applications such as this.
 
Liam Hall said:
I’ve got a bunch of them. The one I usually fire up is Pocket Light Meter. The other good one is Cine Meter.
Click to expand...

Cine meter made a “ii” version right? I liked that one. Seemed to have a lot of potential. What features make you reach for that app first these days?
 
James0b57 said:
Cine meter made a “ii” version right? I liked that one. Seemed to have a lot of potential. What features make you reach for that app first these days?
Click to expand...

Yes, they made a paid update. The original is free. I mainly use the Pocket Light Meter to get a ballpark on the colour temperature.
 
I use a little device called Lumu which is similar to the phone apps but with a small lightmeter style cone that plugs into the phone/ipad socket. At first it was just a toy but it has become super handy, especially in rushed setups. I guess I use it similar to how one would use a proper colour meter but at a much much lower cost. Also works great when you have those pesky lights that don't give you a temp, just unknown notches between 2000 something and 6000 something. Take a reading of the light and it will give the temp and the +/- gel you need to get it to match. Also saves the dance of turning the dial, walking back to the camera/monitor and checking and then going and turning it again and so on..

Since using it regularly I have become less agitated about which monitor to believe (if any!) and making constant small adjustments to the lights hoping they match.
 
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