Painting FOH Bulbs

[crippit]

Firstly I work in a school, and while there might be plenty of smart solutions here, there is so much red tape and talking in circles I just need to solve my current issue.

We have 60 5000k LED bulbs for FOH which were purchased without consulting with us, we need around 120 for all our fixtures. Obviously 5000k is pretty cold for a theater space, and we'd like to get something a lot warmer. We now need to buy the remaining bulbs, but replacing the existing ones (still in their boxes 3 years later) is apparently not possible.

Is there something which we can paint the bulbs we already have with in order to reduce the colour temperature? Is there another solution?

 

[microstar]

Do you have a photo of the fixture the LED's fit into?

 

[crippit]

I don't, but I'll snap one tomorrow!

 

[almorton]

If you can gel the fixtures maybe the correction pack listed here would be worth a look - once you work out which gel works best you can order up a sheet or two.

 

[JAC]

No, I don't know of any kind of coating you can apply to the lamp to accomplish this. But as almorton says there are gels specifically for this, called CTO (color temperature orange). They come in a range; 1/4 CTO, 1/2 CTO, and full CTO. Gel is cheap, I would get one of each and experiment, although to go from 5000k to tungsten I would guess you want 3/4. The problem you're going to run into is figuring out some way to mount them. I assume these are LED, so at least heat will be negligible. By FOH, it sounds like you mean house lights. Theatrical fixtures have a way built in to mount gel, but houselight fixtures (mostly) don't. If you're lucky your fixture has some kind of lens and you can mount gel inside of that.

 

[almorton]

Note to add - there's almost certainly an equivalent set of Rosco gels, but I'm not familiar with Rosco colours. Rarely used them, except in a colour scroller, which will give you an idea of how long ago that was likely to have been.

Edit to add: it's worth noting that the Lee Zircon gels I linked to are specially designed for use with WW and CW LED fixtures. They are different to the gels for tungsten, as the spectrum produced by LED fixtures is different to tungsten, being somewhat discontinuous.

 

[microstar]

Rosco 3/4 CTO has a transmission percentage of only 58%, so a lot of intensity would be lost in the process. Something to consider as well.

 

[RickR]

Almost anything paint, dip, pen, wrap can change the lights color. But several issues will come up.

I'm sure you've thought of most of these, but here is what comes to mind. Safety first of course. Even just flakes pealing off the lamp will trigger nasty audience reactions. LEDs are cool-ish, they can get too hot to touch. Longevity of your treatment should be considered. These lamps could be in place for 10-20 years! Lastly I'd think about consistency. Paint type stuff doesn't have the control you might want.

 

[macsound]

Gel is your best option.
Not sure what the fixture looks like or if there's any sort of accessory slot to insert the gel into, but I've had good luck in retail spaces before gluing a gel to the front of a LED bulb. I would always glue as close to the edge of the lamp face as possible, assuming the majority of the focused beam, and therefore heat, radiates from the center.
Best to have a test unit on your bench first to ensure the glue doesn't melt. E6000 is usually my go to for light bonding.

 

[RickR]

Oh yes,
There used to be accessory holders for bare PAR lamps. I mostly used the MR16 ones but they were made up to PAR38. Front and back halves screwed together to trap a lens or louver. They would be ideal with Roscos dicroics. A pricy but permanent option, but maybe plastic discs and gel?

 

[Apmccandless]

You should try Rosco Colorine. The golden amber would maybe be too yellow but maybe not. Since it is designed to dip incandescent bulbs the heat shouldn't be an issue since it would be lower temp than the incandescent version.

 

[cbrandt]

It is worth considering and comparing the cost of mitigating/fixing the wrong lamps compared to just re-sourcing the right lamps. A LOT of effort can go into a "fixit" solution that ends up costing more and looking worse.

 

[crippit]

Here's a link to some photos. They're a long way up! https://photos.app.goo.gl/6VZftGrwwViPgVy38

I'm in agreement that doing it right the first time is the best way, but unfortunately school budgets are super tight.

 

[ship]

"Firstly I work in a school, and while there might be plenty of smart solutions here, there is so much red tape and talking in circles I just need to solve my current issue.
On
We have 60 5000k LED bulbs for FOH which were purchased without consulting with us, we need around 120 for all our fixtures. Obviously 5000k is pretty cold for a theater space, and we'd like to get something a lot warmer. We now need to buy the remaining bulbs, but replacing the existing ones (still in their boxes 3 years later) is apparently not possible.

Is there something which we can paint the bulbs we already have with in order to reduce the colour temperature? Is there another solution?" - Crippit

You are in Canada so color dip if still available is probably not an option, much less how in presumed LED A-lamps how it would stick or perhaps bun into the normally plastic of a Plastic globe. Color dip is nasty and to avoid - sorry. Gel good and given the lack of heat could seem to work, but the LED lamp woks different than full spectrum incandescent lamps. Color correcting gels for a LED A-Lamp likely won't work much.

Important to know what fixtures you are using the lamps in to start in assuming a A-Lamp style LED being in contention to replace.

Next step, are they dimmable with assumed dimmable lamps to control a now LED source in dimming properly? This might be a better start to your fight. What's the color rendering index LED rated value of the LED lamps installed? That might be another point of contention...

On the other hand, while 5,0K is not quite daylight in gelling for it, it is a very happy color temperature for a work light or audience light as possible in what you above also might describe. If the case of warm white/Cool white for the audience, if dispersed in color temperature should be fine in other than audience noticing. The audience will in that case note it in forcing if audience lights... probably the warmer color temperature. If audience lighting you describe - more information needed.

 

[Vince]

Just a thought which maybe could work: embrace the difference and place the (c)old ones alternately with the new warmer ones. When done consistently chances are anyone thinks it's designed that way.

 

[Les]

Just a thought which maybe could work: embrace the difference and place the (c)old ones alternately with the new warmer ones. When done consistently chances are anyone thinks it's designed that way.

Years ago I visited a convention center with what appeared to be a 50/50 mixture of Metal Halide and HPS fixtures, laid out in a grid pattern in a seemingly deliberate way. The "orange" fixtures could have been color-corrected MH as well, but I've often wondered about the purpose of that install. The theory I came up with was maybe an effort to achieve three approximate color temp ranges: Warm White, Cool White, Daylight.

While maybe not preferable in a theatrical house light system, adopting a pattern or other "rhyme or reason" can at least make it look somewhat aesthetically pleasing, especially to the uninitiated. Many of the new professionally-designed 100% LED high school auditoriums in my area have adopted a ~4000K house light colortemp. Not my cup of tea personally, but they did at least avoid having the spaces appear too cavernous.

 

[crippit]

"Firstly I work in a school, and while there might be plenty of smart solutions here, there is so much red tape and talking in circles I just need to solve my current issue.
On
We have 60 5000k LED bulbs for FOH which were purchased without consulting with us, we need around 120 for all our fixtures. Obviously 5000k is pretty cold for a theater space, and we'd like to get something a lot warmer. We now need to buy the remaining bulbs, but replacing the existing ones (still in their boxes 3 years later) is apparently not possible.

Is there something which we can paint the bulbs we already have with in order to reduce the colour temperature? Is there another solution?" - Crippit

You are in Canada so color dip if still available is probably not an option, much less how in presumed LED A-lamps how it would stick or perhaps bun into the normally plastic of a Plastic globe. Color dip is nasty and to avoid - sorry. Gel good and given the lack of heat could seem to work, but the LED lamp woks different than full spectrum incandescent lamps. Color correcting gels for a LED A-Lamp likely won't work much.

Important to know what fixtures you are using the lamps in to start in assuming a A-Lamp style LED being in contention to replace.

Next step, are they dimmable with assumed dimmable lamps to control a now LED source in dimming properly? This might be a better start to your fight. What's the color rendering index LED rated value of the LED lamps installed? That might be another point of contention...

On the other hand, while 5,0K is not quite daylight in gelling for it, it is a very happy color temperature for a work light or audience light as possible in what you above also might describe. If the case of warm white/Cool white for the audience, if dispersed in color temperature should be fine in other than audience noticing. The audience will in that case note it in forcing if audience lights... probably the warmer color temperature. If audience lighting you describe - more information needed.

Thank you for your reply! They are the architectural lights for the house. They're indeed LED and they're going to be connected to 6 zones run by ETC Foundry Dimmers controlled by an ETC Mosaic system and via an ETC Element during shows. The bulbs that are currently installed are incandescent. I would guess in the range of 3000k.

I hope that this gives the information that you are looking for?

 

[almorton]

Just a heads up - LEDs on dimmers might not behave themselves very well anyway. It depends so much on a lot of factors; the LEDs themselves, of course, whether the dimmers are leading or trailing edge (or sinewave, and I'm not familiar with Foundry dimmers) and whether you've got enough load (some incandescent with the LEDs for example) to stop the triac snubber circuits from leaking enough current to make the LEDs flash when off. You're unlikely to get a nice smooth, linear fade like you do with incandescent.

 

[jtweigandt]

I would get a small amt of Gel and see what that does for you. As those look like can fixtures, if they are accessable from catwalk above, I would probably pull one to play with back on terra firma. You will do better with gel if your supply of bulbs has a high Color rendering index.. the more recent bulbs pay more attention to this meaning you have more broad spectrum light to work with besides the predominant color temp. The older ones tended to be very narrow around their specific color meaning there's not much orange to work with when you filter out the blue end. I personally would cut gel to size, (round) and use either a 3 d printed X in a circle frame that you could drive a sheet metal screw into, or less elegant, just a horizontal sheet metal X with L bent into the ends to interface with the can, and sheet metal screw. If you have an industrial arts program in the school, they could probably produce either for you. That way your gel just sits captive on top of the frame, and could be replaced simply by pulling it out and gently stuffing a new one in. And ditto on making sure there is an incandescent load in the lineup to smooth out the dimming. It worked wonders for me when I did an LED conversion in our space.

 

[crippit]

The foundry Dimmers are designed for an LED load. These are all interesting suggestions. Thank you !