Film-Tech Forum ARCHIVE: reflector flaking / re-silvering Q

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Posted by Scott Norwood (Member # 30) on 03-29-2011, 08:51 AM:

This is a new one for me: two-machine booth with Super Lume-X lamphouses, running 2kw xenons. The lamphouses only have about ~1000 hours on each and are about fifteen years old. The reflector in one of the lamphouses is flaking around the outer edge; the flaking appears to be even around the entire reflector, and is about 1 1/2 inches from the outer edge. The other reflector is fine.

I suspect that this may be heat-related damage, as the roof exhaust blower has failed, and several shows have been run since it last worked. Still, I find it curious that one reflector is fine and the other is damaged (there is a common exhaust system for both). To my knowledge, there have been no bulb explosions or other damage in this lamphouses. I just noticed the flaking over the weekend; it is possible that it predates the exhaust problem.

Has anyone dealt with Ultra Flat or anyone else who re-surfaces reflectors? Have the results been adequate? Have there been any issues with matching color temperature or brightness with another projector? Is the lifetime of a re-silvered reflector equal to that of a new one? Is there any reason to buy a new reflector instead of having a bad one re-silvered?

Posted by Jeff Taylor (Member # 443) on 03-29-2011, 10:12 AM:

I've seen threads about resilvering with Ultra Flat and the results were described as great. No idea of the cost, though. Supposedly they only work through dealers, but others have said they worked directly with them. Why not call?

Posted by Louis Bornwasser (Member # 3063) on 03-29-2011, 02:28 PM:

If the flaking is only around the OUTSIDE, it is NOT heat related. Strong (& others) had a raft of poorly coated reflectors about 17 years ago. I would disregard and move on.

(If the flaking was on the inside, then I would repair and would suspect heat.)

Not much light from the extreme outside of any reflector. louis

Posted by Tony Bandiera Jr (Member # 2365) on 03-29-2011, 06:55 PM:

Think this might be a problem? [Eek!]

This is on my #2 35mm at UC Irvine. Believed to have been caused by lack of cooling when the building EMS shut down my exhaust blower in the middle of a screening. The blower is several stories above my both and the booth was fairly cold that day so I didn't notice the blower had shut down until after the screening. [Mad]

Posted by Scott Norwood (Member # 30) on 03-29-2011, 07:25 PM:

Interesting. My flaking looks similar to Tony's, except that it is even around the entire circumference of the reflector (same degree of flaking all the way around), and not anywhere near as severe.

It is on the inside (silvered surface) of the reflector, but near the outer edge (approximately the same position as in the picture above).

If no one has had a negative experience with Ultraflat, I will suggest that the owner of the equipment go with that option.

Posted by Louis Bornwasser (Member # 3063) on 03-29-2011, 10:22 PM:

Ultrafalt does a good job; they only do the reflect part. No heat coating. Louis