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Hi

 

Can someone tell me who makes good (temperature resistant) gels for tungsten lights in

custom sizes (so that I can cut it myself), preferably large sheets

 

I've tried lee at bhphotovvideo, but they sell only small sizes (up to 4x4 inches)

 

I need size at least 20x20 inches or maybe in large rolls.

 

Who makes, and who sells it at large sizes (I need to buy it over internet, since I'm here

in the middle of nowhere)

 

thanks

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I found a neat little product from GAM called Heat Shield 99. It's an optically clear thermal insulator that protects color filters (gels) from fading and warping due to prolonged exposure to high intensity light sources.

I personally like Rosco corored gels and Lee diffusion. I'm sure that you can find a dealer within a few hours of you that can ship the gels down or just order straight from Rosco, Lee and GAM websites.

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I've checked out the heat shield you mentioned, looks like a neat thing, and if it does any help I'll buy it.

 

And as for filters, well I've looked at the Lee site, but It doesn't seem as they are selling it directly from there..

Lee seems to offer just the right sizes, and they sell in roles too, "201 full" would be just what I need

 

But first I'd like to hear if someone had any experience with Lowel gels, what reputation do they have

compared to Lee and Rosco?

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Been searching some more, and It seems Rosco also sells the heat protection shield, plus BHphoto sells almost every Rosco filter there is.

 

So, to summ up all my questions:

 

Which last longer (on lower output lights, mine are up to 1250W) if placed about 10cm from the protective glass:

Lowel, Lee, Rosco or Gem

 

Also, which heat protection sheets protects better, Rosco or Gem

 

 

Any experiences, surely all you cinematographers must have had some experience with all of them..

 

 

thanks

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I'm mostly talking to myself in this thread...

 

but I noticed the other thread about gels here, and there it is mentioned that Rosco gels take more heat than Lee filters.

There are 20x24'' sheets for $5.50 on BH photo. There are also heat shields from Rosco for about $12

I think I'll get that

 

But can someone tell me, which Rosco filter I need for converting from 3200K to 5600K ? (which filter number)?

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Sorry, one more question:

 

How many hours (with heat shield) can I expet from a Rosco piece of gel, mounted on barn doors (outside), 10cm

from a cooled 1250W lamp that has protective glass in front ?

Does it eventually melt, or does it never melt if everything is ok. In case of the second answer,

the first question goes for fading of the color.

 

thanks

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I've never used a heat shield gel. But I have used CTB on 1K Babys and clipped them on barn doors with C47s. Didn't experience any melting and I believe I've had them closer than 4" (10cm) at times. I can't remember how long I had them that way but it must have been hours (half day even).

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So what happens to them after half a day?

 

They are intact. No melting, burning, etc. Admittedly, I haven't used CTB on an open-face tungsten fixture for that long so it could have problems (only used them on fresnels). I've used diffusion on a 1K open face but given that CTB would absorb a lot of that light energy...

 

If you're really concerned, you could mount the CTB on a frame (2x3 or 4x4) and put it a fair distance away.

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As I understood your last post, they lasted for a half a day and then you had to take another one.

Have I misunderstood it then?

 

What I'm asking is how long can they serve (in total hours) for their purpuse, before fading or something..

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Sorry I wasn't clear. I've used them as long as half a day (4-5 hours) without any noticeable damage to the gel. I've never used them more than 4-5 hours so I don't know what happens beyond that. But I'd think that if it went that long without melting/burning/warping, it will probably last the whole day that way. Though, as I said before, this is on a fresnel. The open face will throw more heat at the gel.

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And how many days can you use one piece of gel before the dye fades?

 

Hi,

 

With small lights gells can last a long time, if care is taken. With large HMI's gells can fade/burn while you watch! Sorry I can't be more precise!

 

Stephen

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Most movies and commercials use Rosco or Lee gels on rolls. I have never seen lowell gels on a movie set. They may be catering their gels to ENG types. Very small jobs that are cost concious will buy a few sheets of something. But it generally cost effective to have a roll around.

 

Rosco makes two types of heat shield. One type that is a liitle thin and comes on a roll. This type of heat shield will help most gels from getting burned up whether they are on a frame or on the doors, but don't let the gels touch while in use. They will melt together. Seperated they will be fine.

 

Rosco also make a gel that only comes in sheets call thermashield. It is expensive costing around 50 bucks US a sheet. This stuff is great for say firestarters in par cans or on use with tabletop food commercials. It really cuts back on the heat output of a lamp, but the right side must face the lamp for it to work. An electrician can use a continuity meter to find the right side if it has not been marked.

 

http://www.rosco.com/us/filters/protect.asp

 

Best

 

Tim

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Thanks

 

 

One more question..

 

Can lighting gels be used in front of lenses.

I have a nice bellows hood with a gel holder, but I don't know wheather this kind of gel can be used.

My hunch tells me that the worst thing that can happen is loosing contrast due to the dirt on the gel, but

is there other possible problems?

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Ok, now I have a headache...

 

It seems there are lots of series of Rosco filters, the tungsten to daylight filter that I need is

available in Cinegel and E-colour lines.

What's the difference between CInegel and E-colour filters?

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Email Rosco, Lee, GAM, Lowel, etc. and ask them for free gel swatches. I've got a ton of these sitting on my desk right now. I have #02 Bastard Amber sitting on a gel frame right in front of the lens on a 2K Fresnel right now. I put a new one in about once a month and use the light every second day. It depends on the wavelength of the color (purple will fade a lot faster than amber).

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That sounds grate Chris

 

My lights never are turned on for longer than say 5 minutes at a time, as long as it takes to set it up, take a reading, and then expose the film, and I don't use them every day

 

So considering you switch once a month, and assuming your lights burn for a long time (for cinematography), I think two sheets (cut into 8) will last more than a year, possibly two for me.

 

I've decided to buy Rosco gels, but still I can't make up my mind wheather I should buy Cinegel or E-colour

 

anyone know what's the difference?

It says Cinegel gels are deep dyed, is that good?

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You mean the light scatters insite causeing loss of resolution?

 

Filip,

 

Yes, also they may scratched, too thick to place behind the lens & not optically pure.

 

Kodak gelatin filters, which are very expensive and small are optically very good.

 

Stephen

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Thanks

One more question..

 

Can lighting gels be used in front of lenses.

I have a nice bellows hood with a gel holder, but I don't know wheather this kind of gel can be used.

My hunch tells me that the worst thing that can happen is loosing contrast due to the dirt on the gel, but

is there other possible problems?

 

---Since they're not optically flat they'll randomly defract the light.

You'll get diffusion at best and sometimes rippley images.

 

---LV

Edited by Leo A Vale
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Well I've made by decision. I'll get Rosco Cinegel instead, from descriptions of Rosco, it sounds better than this E-colour, well if anything, it didn't get an Oscar for nothing.

It's deep dyed, on a heat resistant polymer. In combination with the rosco heat shield it should last.

I'll take two sheets, and cut them in 8, I'll take one sheet of heat shield and cut it in 4.

I've also ordered every kind of Swatchbook from Rosco that they offer (directly from Rosco),

I'll use these with flashes, they will cover a small flash unit pretty well.

 

thanks everyone for their help

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