Properties of Gel

Hey, quick question here:

Would regular gel be considered a plastic? I ask because I need to find a proper glue to adhere gel to a high temperature metal, in a situation that hot glue is not appropriate for.


Cheers!

James

 

Modern "gel" is plastic (except diachronics), however some gels have the pigment on the outside as a coating, others are impregnated. Because of this it may not react to glue the way you would hope.

 

Thank you kindly

 

Apollo and Lee gel are double coated polyester for color consistancy, while Rosco and GAM are dyed polyester. The Lee HT consists of polycarbonate material, which has a higher resistance to warping and color migration.


(Edit- Wow Footer, you know when I sit down and open the 'Booth, now don't you?!)

 

ok....I love Apollo gel (and most Apollo products - I use scrollers, rotators, gel, gobos, and more), but recently needed a few sheets that day and the only ones in town that were in stock were Rosco. I bought 8 sheets of this nice purple for use on S4 pars and put them in place. It was a conference at the convention center and the pars were used to uplight fabric columns. After about 2 hours, I got called from the interior decorator that had been hired to design the fabric, flowers, and decorative lighting. She said that the lights weren't purple anymore. I inspected the gels, and they had completely washed out. There was a hint of purple at the edges, but no color at all in the middle. It was not burned or melted, just no color.

Our theory is that this was old gel. The one shop in town that stocks gel has at least 20 of every color that Rosco makes, so it is possible it has been sitting there for years. Is this possible?

 

I noticed at Disney that they were using diachronic plates in most of the stationary indoor S4's. Guess they got tired of changing gels! Sounds interesting, but I am sure expensive to use in 6 inch frames, and many of their 64's (8 inch frame) were that way as well. I would suspect for the rest of us that they would be too fragile. Anybody else using them on here?

One funny effect, when you are off axis, the gel is of course a totally different color! Always a bit of a brain tease to see a light that looks to be gelled yellow throwing a deep violet beam! Kind of a neat effect...

 

As odd as it seams, the VNSP (and even ACL's) actually produce the most even output across the surface of the lamp. This is due to the fact that the lamp is working more like a beam projector, using mainly the reflector to direct light. (Of course beam projectors have the lamp front blocked and pars don't.) The wider floods use a lens much like a headlight. The high refraction ridges disperse the light, but also serve like magnifying lenses (at close range) and produce hot spots on the gel. Although there are some exceptions, I must admit that I observed the same lifespan issues when using the large par based shows popular back in the 80's.

 

I think the issues you are having are a combo of light and heat. If possible, be sure that you have ample space for the heat to escape especially if the fixture is point directly upwards. I see these types of issues with bigger fixtures (2K tung and HMI). You have got to have space for the heat to go. Also, if you are working with short arc / HMI / HID light sources, look into some UV blocking gel but again make sure that you put some space between the gels.
At one point, I had a local sheet metal shop make up some gel frames for some PAR64's we were using as uplights that held the frame at about a 30 degree angle when it was in the light. This allowed some of the heat to escape and the gel still covered the beam. The colors still faded from the intense beam passing through them but they didn't do so as fast nor did they "krinkle" up.
kw

 

The problem with this theory is that we do this often (at least twice or three times a month) and we have never seen this happen before. Also, the local vendor that stocks all of the gel is a chain and they are required to. They also stock every gobo as well.....but most all of the theatres in town buy from another vendor.

 

Supergel and roscolux are made in the exact same manner. Supergel is the european name for roscolux. Rosco however does use a deep dying process to make their cinegel and storaro gel ranges.