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Topic: Proper Lamp Alignment/Bulb Focus Procedure

Jeremy Weigel
Phenomenal Film Handler

Posts: 1062
From: Edmond, OK, USA
Registered: Mar 2007

posted 07-09-2009 09:13 PM

quote: Brad Miller
Also, if you have to keep readjusting the horizontal and vertical adjustments as you back off on the focus, you have a physical alignment problem and are losing light.

Or just a poorly designed lamp house(Super Hightlight). The front mount on these causes the the vertical position of the front of the bulb to drift as you adjust the focus.

quote: Brad Miller
The "Looney Tunes" method (of which I have never heard it called that before today) will also give you a good idea if your optics are properly aligned. If you can't get good circles, you need to get your tech in there.

All my Super Highlights project warped circles/rings;even with new reflectors.

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Gordon McLeod
Film God

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

posted 07-10-2009 12:15 AM

The super highlight is a relatively good lamphouse
One must align it properly to start with then keep it so

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 07-11-2009 01:00 AM

When I started working with xenon bulbs back in the early 80's with XeTron XHC-35 consoles and ORC consoles, our company tech taught me on bulb focusing and chimed in with the nick of "Looney Tunes" since the display on the screen was so similar to the Warner Bros cartoon openings.

It just stuck with me since..and I've also heard other techs also using the same nick for this procedure...

-Monte

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Jarret Chessell
Master Film Handler

Posts: 288
From: London, Ontario, Canada
Registered: Jan 2009

posted 07-11-2009 02:33 AM

This thread reminded me of something really dumb I did a few years ago...

I was in a booth where the previous people had misplaced or did who knows what with the "keys" for adjusting the lamp. I had to install a new lamp into one of the projectors and align it without the keys..... THIS WAS STUPID... AND DON'T TRY THIS AT HOME... the picture explains the rest of the story... lol

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 07-11-2009 02:52 AM

I had to do basically the same with an old Christie CH-20 console with all the safeties disabled.. and the focus assembly in a dis-array of sorts:

with the DOOR OFF and bulb running (a 2k bulb): I had to adjust the lateral of the alignment by actually moving the assembly on the light table left and right to get alignment center. To do the vertial, it was reaching in close to the igniter to find the adjuster to raise and lower the back end of the bulb. To focus was the same.

I made a makeshift pair of sunglasses with taping strips of black film onto my glasses so I can see the focus through the "snood" and onto the aperture without being blinded.

Luckilly, I was behind the reflector so not to get scalded like Jarret above (and no offense, of course to Jarret..).

I'll never do that again ... The owner of that theatre had this company manager didn't know what the word "SAFETY" was and meant when he wanted me to do this task!

That was totally insane to do!

-Monte

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Jarret Chessell
Master Film Handler

Posts: 288
From: London, Ontario, Canada
Registered: Jan 2009

posted 07-11-2009 12:46 PM

I did that with a 2K bulb... unfortunately I had to lean forward to see the screen. Reaching back into the lamp house with the lamp on didn't thrill me either. I think the really bad thing about the whole deal was that I was only sun burnt on the left side of my face. [Roll Eyes]

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Phil Hill
I love my cootie bug

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

posted 07-11-2009 01:55 PM

quote: Jarret Chessell
...the picture...

Hubba Hubba! [thumbsup]

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Jarret Chessell
Master Film Handler

Posts: 288
From: London, Ontario, Canada
Registered: Jan 2009

posted 07-11-2009 02:05 PM

Phil,

I really really hope that's an integrated anamorphic in your pocket....

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Phil Hill
I love my cootie bug

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

posted 07-11-2009 02:15 PM

YUP! 203mm... [Wink]

(Couldn't resist ...Just yankin' your chain in a good nature...Nothing implied or expected) [Razz]

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Mike Croaro
Master Film Handler

Posts: 394
From: Millbrae, CA
Registered: Apr 2005

posted 07-13-2009 11:48 PM

"Some projectionists .........prefer having it dimmer in the corners and around the sides......."

Folks: You've got to be kidding. Who focuses the lamp so the center is bright and the four corners and sides are dim? This results is a poor presentation.

Mike Croaro

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 07-14-2009 03:21 AM

quote: Mike Croaro
Who focuses the lamp so the center is bright and the four corners and sides are dim? This results is a poor presentation.

Unfort, this is the only way to maintain a good picture due to the way the reflector is in the console.

I saw a large complex presentation on the screen: Center was nice and bright, but you can actually see the darkness on the parameters of the screen. I asked the operator about this. He told me that the chief operator has to run it this way (they had Super Highlight II's running a 6k bulb shooting throught a PR-1050...I can get better light out of a CHR CH-45 Reference console that what that STRONG could even try to muster...) to maintain a decent picture on that huge screen.

They later went digital ....

-Monte

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Gordon McLeod
Film God

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

posted 07-14-2009 07:32 AM

Well actually the corners should measure slightly lower than the centre due to the contrast effects of the black masking
Also the gain of the screen and its geometry will determin hte flatness of field at the end of the day

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Tim Reed
Better Projection Pays

Posts: 5246
From: Northampton, PA
Registered: Sep 1999

posted 07-14-2009 09:43 AM

quote: Dan Reiter
I was taught by one of the old greats, Jim Ezell.

As good fortune would have it, Jim Ezell was the first sound man (as techs were referred to in those days) I ever met, and was the one who inspired me to enter the service field. While Louis Bornwasser graciously took me under his wing for many years and became my mentor, I never would've gotten to that point without Jim Ezell.

Jim worked for Carbons, Inc. when I first met him, and he delivered our carbon. Then he formed a service company with Don Devore (Cinema Techniques) and was our sound man... that's when I said, "Hey, THIS is what I want to do!" He outlined a curriculum for me and was a great help and inspiration over the years. Jim was the best.

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 07-14-2009 10:00 AM

I agree Tim... Jim Ezell was a great guy. It's funny that he also taught me how to properly align a lamphouse way back when Xetron was selling Prevost projectors. Jim taught me alot of stuff in the small number of times I got to work with him back in the early 80's. He is one of the few I ever knew that I would consider a really brilliant technician.

Mark

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Jarret Chessell
Master Film Handler

Posts: 288
From: London, Ontario, Canada
Registered: Jan 2009

posted 07-14-2009 05:02 PM

quote: Mike Croaro
Who focuses the lamp so the center is bright and the four corners and sides are dim? This results is a poor presentation.

I was trying to phrase my instructions carefully to avoid any arguments between members...

One easy thing to point out to make the contrast debate make sense: Most TV manufacturers use black plastic when making their sets. If you ever see a silver coloured TV you'll notice that it looks like it's producing a lower contrast. It's all an eye game, even if the guts of the TV were identical, you would still likely prefer black around the picture. I've also noticed that silver TV's often have a black band around the screen.

... sometimes you do have to sacrifice a lot of light to get it perfectly even anyways...

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