Film-Tech Forum ARCHIVE: Xetron lamphouse bulb

This is topic Xetron lamphouse bulb in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Richard May (Member # 2627) on 11-16-2011, 12:11 PM:

Can a standard length bulb be used in a xetron lamphouse, or do you have to use a short? One of the lamphouses has the new reflector kit that does away with the front spider assembly. The problem is when they put a short lamp in, the front adapter was missing. They are using a temporary piece of metal to hold the front of the bulb on the new front mount. Obviously I just need another front adapter. They have a standard lamp in the booth and I was wondering if they could use it until I find the right adapter.

Posted by Monte L Fullmer (Member # 2797) on 11-16-2011, 01:46 PM:

If that lamphouse is a XTC-35 (I think that's the model number) you can use a standard Osram XBO-2000w,CXL-20R, or similar bulb.

But, you mentioned a reflector replacement where a short was used.

Did a Technilight reflector get installed in that lamphouse, in which a XBO-2000wHS was used?

Just that short gap bulbs that short bulbs are known for, is more effective in light output for that reflector than the standard gap bulbs, but you can use a standard until you get that adapter piece replaced.

Posted by Richard May (Member # 2627) on 11-16-2011, 04:11 PM:

I don't remember the model number exactly. It's the blue lamphouse, not console. It can take a 3K lamp. Also not sure of the reflector kit. The reflector has an arm attached to the side that extends to the front where the lamp tip rests.

Posted by Steve Guttag (Member # 268) on 11-16-2011, 05:43 PM:

Xetron/Neumade made/make a whole slew of adapters/fittings to work with a range of lamps...including HS models as well as the full-size. So without knowing the lamp adapters, it would be impossible for anyone to say definitively which model lamps will work in your particular situation.

-Steve

Posted by Richard May (Member # 2627) on 11-16-2011, 07:42 PM:

According to the manual, the rear bulb holder is the same for 1,2,&3K lamps. If that's the case the bulb will fit because the front end just rests on the bracket. Will the position of the elctrodes be a problem because they are now in a different spot, or is there enough play in the focus to compensate?

Posted by Louis Bornwasser (Member # 3063) on 11-16-2011, 09:00 PM:

Is this the "small" reflector. (front end is close to the douser)?

If so, Monte is right: use the xbo-2000w/h. The -hs is not usual on this reflector. Louis

Posted by Richard May (Member # 2627) on 11-17-2011, 06:58 AM:

I think it might be. It definitely is narrower than usual. The front "arm" is bolted onto the outside of the reflector and does come pretty close to the douser.

Posted by Louis Bornwasser (Member # 3063) on 11-17-2011, 11:36 AM:

That sounds like the Big Sky conversion of the Xetron. xbo-2000w/h will fit perfectly. The other bulbs may as well if you have an adapter that makes tehm the same size as the 2000h.

Be careful that you have the correct working distance on that reflector. It is not the ame as the old reflector. Louis

Posted by Richard May (Member # 2627) on 11-17-2011, 04:30 PM:

That was going to be my next question. Any idea what the working distance should be?

Posted by Eric Robinson (Member # 2966) on 11-18-2011, 10:58 AM:

quote: Louis Bornwasser
Be careful that you have the correct working distance on that reflector

What would the consequences be if the working distance is wrong?
Possibly lower light output than what is possible?
or
Burning something up?

Posted by Richard May (Member # 2627) on 11-18-2011, 01:23 PM:

I don't think burning anything would be an issue. Light level would be reduced.

Posted by Gordon McLeod (Member # 33) on 11-18-2011, 02:19 PM:

If the working distance is wrong and one over adjusts the bulb focus to try to compinsate one can quickly scorch a reflector

Posted by Monte L Fullmer (Member # 2797) on 11-18-2011, 04:19 PM:

...seen plenty of STRONG X-90 reflectors with the back section all scorched and even warped due to bulbs being focued too far back - even the chrome was peeling from the inside surface.

Posted by Eric Robinson (Member # 2966) on 11-19-2011, 12:50 AM:

Well if the reflector were of the eliptical type then you would reason that the bulb midfocus position would be foci(1) and foci(2) would be positioned at the film trap, but I'm guessing that the reflectors are possibly not perfect elipses and you would therefor have to rely on specs from the engineer who designed the reflector for the working distance spec. Is this correct or is there some trick to reverse engineer it? I guess its kind of late to talk about it, but I have always wondered about it.