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Left-right and up-down are no problem, but keep an eye on that focus adjustment. The Big Sky design for the focus mechanism is a lame one IMNSHO--the ones I've seen bind up when they're being adjusted towards a cooler position (away from a hotspot condition). (The follower pin on the bulb carrier sled rides up the focus cone instead of sliding along it, lifting the bulb carrier sled off its guides and binding it. There is a spring fitted to keep the sled pressed against the guides, but it isn't strong enough to prevent the pin from riding up on the cone). If you're adjusting focus away from a hotspot and you don't see a change on the screen, the mechanism has bound up and you'll need to unbind it. Otherwise vibration will eventually release the strain on the mechanism, causing a change in focus back towards the hot end. I've seen one print get blistered when this focus change occured during the first show after a lamp change.

When you focus you might want to start with the lamp set towards the cool end (dark center screen) and adjust toward hot--the sled doesn't bind when it's going in that direction. If you have to adjust away from a hotspot condition, try vigorously wiggling the Allen wrench as you go. Or rock the adjustment back and forth after each couple of turns in order to get that sled to settle back down on its guides. Both are pain in the ass techniques for sure. Perhaps someone else here has a better way, but that's what Dave Huskinson and I have seen to work for now.

Have fun!

Paul
SMPTE Hollywood Section
Still gimpy and once again mercenary projectionist
"When the money runs out, so does I."

I'll bet the one in the centre is vertical; the one on the right is focus.

That leaves the one on the left...lateral.

If I were removing a bulb, I certainly would molest...er...uh...handle it properly, but like I said, I'm not removing it this time.

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