Color Correction Gels for Cheap LEDs

ACTSTech

Well-Known Member
Joined
Nov 13, 2019
Location
USA
Since I have time on my hands, I've been fooling around trying to get the cheap LED pars to not look like really cheap LEDs. I've tried all kinds of Rosco Color correction, but they still look sickly blue-green. Anyone have ideas besides placing them in the dumpster (which I've thought about) and drinking heavily (which I've done). I'm not asking for miracles, just wondering if anyone had creative solutions.
 

sk8rsdad

Well-Known Member
Premium Member
Fight Leukemia
Joined
Aug 15, 2008
Location
Ottawa
It would help to know a little more about the fixtures in question. Are they a white LED, RGB, RBGA, or something else.

If they are white then you're likely stuck. White LEDs use a blue emitter and a phosphor to create white light. There isn't any way to add some red by putting a subtractive gel on it. All you can do is reduce the blue and the lumens along with it.

If they are RGB(AWUL?) then there may be a way to blend to get a different colour. It may never give you a good enough full spectrum white though.
 

ACTSTech

Well-Known Member
Joined
Nov 13, 2019
Location
USA
It would help to know a little more about the fixtures in question. Are they a white LED, RGB, RBGA, or something else.

If they are white then you're likely stuck. White LEDs use a blue emitter and a phosphor to create white light. There isn't any way to add some red by putting a subtractive gel on it. All you can do is reduce the blue and the lumens along with it.

If they are RGB(AWUL?) then there may be a way to blend to get a different colour. It may never give you a good enough full spectrum white though.
The fixtures in question, as I said, are junk :)

They're Stage Ape Wide 64s. At last check, the company is gone, no information available other than a few random sources. The lights are RGB, no white or amber or lager or porter :cool: Surprisingly, ETC already had a profile of them in the EOS software, so Stage Ape must have flooded the market at one point with enough cheap Chinese junk that ETC felt the need to accomodate them.

Like I said I was just wondering if someone knew a trick. I've tried looking at gels that cut the 400-500 nm range, color correction, drinking heavily, you know, things to do to pass the pandemic lock-in. So far the only thing that works is the drinking...
 

derekleffew

Resident Curmudgeon
Senior Team
Premium Member
Joined
Aug 21, 2007
Location
Las Vegas, NV, USA
IMO, the LED conversion kits for Mini-Mag flashlights looked most "natural" with the equivalent of 3/4 CTO. I wouldn't vouch for CRI or anything, but that's what worked for me.

I've tried all kinds of Rosco Color correction, but they still look sickly blue-green.
In that case, I recommend my default Xenon Super Trouper combo: 1/2 CTO + 1/4 Minus Green.

I've never looked into the "Specifically for LED" filters from LEE Filters (Has anyone?), but you might try those. I think they are more for white variants. Probably nothing one can do to "fix" RGB units.
 
  • Like
Reactions: RonHebbard

ACTSTech

Well-Known Member
Joined
Nov 13, 2019
Location
USA
IMO, the LED conversion kits for Mini-Mag flashlights looked most "natural" with the equivalent of 3/4 CTO. I wouldn't vouch for CRI or anything, but that's what worked for me.

In that case, I recommend my default Xenon Super Trouper combo: 1/2 CTO + 1/4 Minus Green.

I've never looked into the "Specifically for LED" filters from LEE Filters (Has anyone?), but you might try those. I think they are more for white variants. Probably nothing one can do to "fix" RGB units.
I've got Lee 205 1/2 CTO on it and if I run them with an R 02 Bastard Amber setting they're sort of iffy but still not great. I'll see what the 1/4 minus green added looks like sometime.

As I've suggested, the best fix is to put them in the dumpster where they belong, but it's not like I have other lighting projects at the moment...
 

sk8rsdad

Well-Known Member
Premium Member
Fight Leukemia
Joined
Aug 15, 2008
Location
Ottawa
The trouble with using a gel is that it can't add a colour that is missing from the spectrum. There's nothing it can do other than remove a little of the colour that is produced by the LED, which is pretty narrow spectrum around its nominal red, green, or blue. Adding an amber is pretty much the same as dialing down the blue a little bit, but less efficient.

Rather than a dumpster, buy something else that gives you a broader spectrum white light and add it to the rig. There's nothing wrong with the RGB fixture. It's just being asked to do the wrong job.
 

jtweigandt

Well-Known Member
Joined
Aug 2, 2013
Location
Moline Il
The trouble with using a gel is that it can't add a colour that is missing from the spectrum. There's nothing it can do other than remove a little of the colour that is produced by the LED, which is pretty narrow spectrum around its nominal red, green, or blue. Adding an amber is pretty much the same as dialing down the blue a little bit, but less efficient.

Rather than a dumpster, buy something else that gives you a broader spectrum white light and add it to the rig. There's nothing wrong with the RGB fixture. It's just being asked to do the wrong job.
Bingo There are times you may want a single color wash for effect, and they will still be good to have
 

ACTSTech

Well-Known Member
Joined
Nov 13, 2019
Location
USA
The trouble with using a gel is that it can't add a colour that is missing from the spectrum. There's nothing it can do other than remove a little of the colour that is produced by the LED, which is pretty narrow spectrum around its nominal red, green, or blue. Adding an amber is pretty much the same as dialing down the blue a little bit, but less efficient.

Rather than a dumpster, buy something else that gives you a broader spectrum white light and add it to the rig. There's nothing wrong with the RGB fixture. It's just being asked to do the wrong job.
I understand the issue with the output and color temperature issues. It's like when I first started playing with the old Coemar LED washes. They were okay, but just never "looked" normal, but as I've said before, when you grow up on 1000w PAR 64s, you get used to that look. Then they added a white, which didn't help. Then they added amber, which helped a little, but it still looked blue/green to me, so I spent way too much time trying to get it to look like my PAR cans. I still haven't seen too many instruments that look like the old cans, they lack the punch and the saturation that I'm used to, but it's an evolution, because I know tours have adapted and evolved, I have to as well.

These cans, however, are not worth adapting to. Maybe for a little bar stage, but over 10' trim they disappear. Thanks for the thoughts though. I agree that maybe just a single color wash could work. I'm just lamenting the fact that I have a lot of time on my hands with nothing to light...
 

Ancient Engineer

Well-Known Member
Joined
Sep 21, 2017
Location
Sandusky, Ohio
What you can try: https://www.leefilters.com/lighting/zircon.html

I have had satisfactory results with these. Hopefully your sources have enough spectrum to be useful.

LEE offered a sample pack at LDI when they introduced these... maybe you could get one?

Some simple sentences guaranteed to start a fight:
"Jazz is just an excuse to play wrong notes."
"PAR cans are awful light sources."
"I only use (insert name of filter company here) filtering because its the best."

Your mileage may vary...
 

Calc

Well-Known Member
Joined
Jan 26, 2004
Location
Mid-Michigan
They're Stage Ape Wide 64s. At last check, the company is gone, no information available other than a few random sources. The lights are RGB, no white or amber or lager or porter :cool: Surprisingly, ETC already had a profile of them in the EOS software, so Stage Ape must have flooded the market at one point with enough cheap Chinese junk that ETC felt the need to accommodate them.
A co-worker bought a bunch of these for us years back to use in our dinner space. Can confirm, they're garbage at mixing anything close to white light. We use them for accent uplights so I've hung on to them for that use, but they're just chinese mass-produced first-gen LEDs. These fixtures could be the definition of "Generic RGB."

If yours are even a couple years old, open them up to check the PSU inside- the tail that plugs into the driver board is absurdly brittle. Not a part that needs to move often, but if it does the plastic strain relief/casing on the connector will crumble into pieces. A couple of ours got jostled around by a loose AC tail and crumbled on their own.
 

ACTSTech

Well-Known Member
Joined
Nov 13, 2019
Location
USA
A co-worker bought a bunch of these for us years back to use in our dinner space. Can confirm, they're garbage at mixing anything close to white light. We use them for accent uplights so I've hung on to them for that use, but they're just chinese mass-produced first-gen LEDs. These fixtures could be the definition of "Generic RGB."

If yours are even a couple years old, open them up to check the PSU inside- the tail that plugs into the driver board is absurdly brittle. Not a part that needs to move often, but if it does the plastic strain relief/casing on the connector will crumble into pieces. A couple of ours got jostled around by a loose AC tail and crumbled on their own.
When we got ours, a few were dead on arrival. I opened them up and like you said, the connectors were already broken. I replaced a few with some compatible old laptop computer supplies and they seem to be alive and kicking still. The XLR jacks are touchy, the DMX dip switches don't always work and the electrical out plugs are pretty much garbage. They look like a nice PAR can from a distance though!

Used ours for the first time as a test run in the new venue this weekend. No way I'd be satisfied with just them, but I dropped in some Altman 360Qs and it's close to acceptable.
 

TimMc

Well-Known Member
Premium Member
Joined
Feb 15, 2017
For those interested in the science of color and human perception thereof: the 2nd hour of Alex Lindsay's Office Hours zoom conference from 1/29/21, link URL takes you to Ray Maxwell's excellent intro to color.
 

macsound

Well-Known Member
Joined
Jun 15, 2018
Location
San Francisco, CA
For those interested in the science of color and human perception thereof: the 2nd hour of Alex Lindsay's Office Hours zoom conference from 1/29/21, link URL takes you to Ray Maxwell's excellent intro to color.
I'm glad to see there are others watching Alex's office hours. I've always wanted to participate but waking up at 6am to be in another zoom meeting is way outside of what I want to commit to.
 

jtweigandt

Well-Known Member
Joined
Aug 2, 2013
Location
Moline Il
Just for laughs, I bought a 90% CRI 120 watt equivalent dimmable LED flood light "daylight" color temp. and put it in next to all the regular 150 watt floods in our footlight fixtures. (they tend to be a warmer white) They have some pretty saturated Gel in them.. and YOWSA the LED punched through the dark amber like it wasn't there. Similar with the pink.. The deep blue fared slightly better. Wish I had the Rosco numbers.. So yes cheap LED has some frequency deficiencies, but Looks like gel has some frequency holes as well at the upper color temp range. And dimming was very steppy on the LED.. But hey.. what's life without the occasional experiment?
 

aeh20s

Active Member
Joined
Oct 15, 2013
Location
Northern Virgina
I realize this might not be exactly what you're looking for, but I just bought these for my photography LED panels to see what they can do. I haven't used them yet, but they're made by Lee so they've gotta be pretty good.

 

Users who are viewing this thread