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Author Topic: Super Lume X Reflectors
Don Furr
Jedi Master Film Handler

Posts: 509
From: Sun City, Ca USA
Registered: Nov 2002


 - posted 03-11-2010 08:26 PM      Profile for Don Furr   Email Don Furr   Send New Private Message       Edit/Delete Post 
I'm running a Super Lume X lamphouse in my screening room. I picked up another lamp for a spare. One has the silver reflector and the other has the yellow reflector.
Which reflector is preferred?

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99


 - posted 03-11-2010 09:36 PM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
The silver reflector is a "hot" rhodnium one the yellowish one is a cold dichroic who's colour temp will be writen on the back

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Don Furr
Jedi Master Film Handler

Posts: 509
From: Sun City, Ca USA
Registered: Nov 2002


 - posted 03-12-2010 06:21 AM      Profile for Don Furr   Email Don Furr   Send New Private Message       Edit/Delete Post 
Thanks Gordy. This one has 5400 written on the back. Using a 1600 bulb which one should I be using?

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99


 - posted 03-12-2010 08:06 AM      Profile for Mark Gulbrandsen   Email Mark Gulbrandsen   Send New Private Message       Edit/Delete Post 
I'd prefer the silvery rhodium version... The light is closer to sun light and not as cold of light as the dichroic would be. That said the whole setup will also run ALOT hotter! You may experience shorter lamp life as well as a much hotter running gate even with the 1600 watt lamp unless you add a heat filter in the front end of the lamphouse. Note that even ORC 1000s had heat filters!!

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Dave Macaulay
Film God

Posts: 2321
From: Toronto, Canada
Registered: Apr 2001


 - posted 03-12-2010 08:23 AM      Profile for Dave Macaulay   Email Dave Macaulay   Send New Private Message       Edit/Delete Post 
Use whatever looks best to you, the silver one is probably a dichroic with few hours on it from a lower wattage lamp so that it hasn't turned yellow yet.
Rhodium reflectors are fairly rare, and some coated reflectors look quite silvery. Both are a stamped metal form or an electroplated nickel form with either a bare rhodium metal plating or a dichroic coating to absorb some infrared energy. Rhodium coated mirrors have a very uniform effect on the lamphouse's colour temperature, the dichroic coating is not very uniform that way and the colour shift varies widely. There's a LOT more infrared heat energy in the light beam from a rhodium plated reflector, so for even small power lamps you may need a heat filter at the least... which is another dichroic coated element with the same variability in colour shift.
Absolute colour temperature is only an issue for studio and lab screening rooms (and possibly a few oddball venues) but is routinely ignored in all platter based commercial cinemas. The few remaining changeover screens should have somewhat matched colour temperatures but nowadays I don't think many techs even look for colour changes on changeovers.
My point, should I have one here somewhere, is that I doubt you have a rhodium reflector. Strong (actually their supplier) measures colour temperature of the coating and codes the reflectors accordingly. Some have an actual number, most have a three letter code like BBD that converts to colour temperature. I don't have the code here but it doesn't matter for a single projector setup, preferably the codes should have the first two letters the same for a changeover setup. If you see such a code on your silver mirror then it is not a rhodium plated mirror. The part number is also different for rhodium ones, and that should be handwritten on the back of the bowl. I don't have this number and it isn't in the Strong price list - showing how unusual it is to find one?
The heat load on the trap and the film itself is much higher with a rhodium reflector. Even with 1500W you will get a very hot trap and may want a heat filter glass in the light path.
The colour temperature with rhodium isn't better than from a dichroic reflector, it is just more consistent. A studio or lab screening room needs (wants?) consistent colour temperature on screen, both projectors and over an extended time. Getting either matched reflectors or heat filters is a major PITA. Setting up the room with rhodium reflectors than matching the heat filters and lenses as well as possible then doing final colour temperature correcting with filters in front of the lenses means a lamp explosion just means a new rhodium reflector and minimal downtime. Using dichroic reflectors would mean an extended closure while a new matched pair of reflectors gets selected and the correcting filters redone.

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Louis Bornwasser
Film God

Posts: 4441
From: prospect ky usa
Registered: Mar 2005


 - posted 03-12-2010 08:59 AM      Profile for Louis Bornwasser   Author's Homepage   Email Louis Bornwasser   Send New Private Message       Edit/Delete Post 
I, too, have never seen a S Lumex reflector without the heat coating.

If yours says "5400" it is very old. The code was meant to stop complaints from theatre personnel starting way back in the 80's.

btw: the very nearly worthless Chrsitie CH-20-25-10 can be made to be nearly as bright as the Super Lumex. Hadden (and others) have made a reflector kit available for at least 30 years. (The Christie is reliable, though!) Louis

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Phil Hill
I love my cootie bug

Posts: 7595
From: Hollywood, CA USA
Registered: Mar 2000


 - posted 03-12-2010 03:25 PM      Profile for Phil Hill   Email Phil Hill       Edit/Delete Post 
Strong Cinema Products uses a 3-letter code to identify the color temperature of their lamphouse reflectors. The code letters are located on the outside surface of each reflector. After decoding, a zero is added in the 4th place of the code to obtain the color temperature in degrees Kelvin. The codes are as follows:



A = 9

B = 5

C = 1

D = 4

E = 8

F = 2

G = 7

H = 0

I = 3

J = 6



Example: Code B J H = 5 6 0 + 0 = 5600°K.

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