January 30, 2016 at 7:06PM


Non-flame Retardant Gels/Diffusion -- Will they melt/burn?

I just recently purchased the Diffusion Pack from Lee Filters that comes with six different kinds of diffusion in the form of 10x12" sheets.

I bought this pack in hopes to find the type of diffusion I like best and then in the future purchase a 48x48" frame and buy a larger portion of the that diffusion.

Here's my issue: These diffusion gels are non-flame retardant. This would be fine if the gels were in a frame on a c-stand away from the lighting instrument, but will these gels be fine attaching to the barn doors of an Arri Fresnel Clones from CAME-TV. The lights in question would be the 1K, 650 & 300.

I just want to use some diffusion for a while without buying expensive frames/c-stands.


I have had no problem clipping Lee color filters to the far edges of barn doors on 300W and 650W tungsten fixtures (6"-8" off the face). I have also seen the same filters melt when clipped only to the fixtures (about 1" away from the face). Since the top and bottom flags are usually larger than the side flags, you can clip to top and bottom and open wide the side flags for extra ventilation.

I think you should be OK, but I would certainly do a 10 minute test (outdoors in a fire-safe area) with the 1K before rigging it for real. In worst case, it will cost you one sheet of diffusion. If it doesn't burn after 10 minutes, you should be good. Do note that if you are aiming your lights down, you should do the test aiming down. If you are aiming your lights up, you should do the test aiming up.

Also, its never a bad idea to have a fire extinguisher on set when working with higher wattage lamps. (Our commercial building code requires that we have such fire extinguishers anyway.)

January 31, 2016 at 5:37AM


Thanks so much for your insight! I would always be clipping these onto the barn doors and never to the actual light, so I'm hoping that it will be a non-issue. I'll definitely run some tests outside once I get the diffusion in the mail. It also seems like my Arri knock off kit runs a little cooler to the touch than the real things. That could potentially be in my favor while using gels.

Adam Wright

January 31, 2016 at 2:54PM

I've had full CTB gels melt when attached to 250 watt Lowel Pro lights, but I wasn't using the Lowel gel-frame that holds the gel a few inches away from the front of the light. Fortunately nothing was damaged, and I just threw away the melted gel filter.

January 31, 2016 at 9:10AM

Guy McLoughlin
Video Producer

Dang. I'm happy to hear it didn't ruin anything. I'll be clipping these diffusion gels onto the barn doors of my lights, so hopefully they will be far enough of away from the actually light to keep relatively cool. I also know that most Lowel lights run extremely hot to the touch. My Arri knock off kit seems to run pretty cool. I'm hoping it all works out. Thanks for the response!

Adam Wright

January 31, 2016 at 2:57PM

I think you will be fine as long as they don't directly come into contact with the lights.

February 1, 2016 at 3:01PM

Michael Militscher
Director / Commercial Producer

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