focussing an Omega Super Chromega D...Help!

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This will seem like a stupid question, but I have no manual to consult and no live body to ask. I throw myself on your patient mercy. I recently tried using the aforementioned enlarger in a community darkroom and couldn't manage to focus it. The lense is a 135 mm componon, and while I could come tantalisingly close to getting the image in sharp focus (a 4x5 neg) I would always ran out of room with the fine focus adjustment. (the twin rails holding the lens assembly hit thier stops.) There seems to be more bellows extension, which is what I need to get the image in focus, and it looks like the carriage that holds the lens can move up and down on a second calibrated track that would allow more extension--I just can't figure out how to release it. There is a big black lever (pointing down) behind the lense board assembly that doesn't seem to do anything. It does look like it might be related to the solution though... What to do? Have I put the negative carrier in wrong or something? Is there a release method for the lense board that will give me more extension? I like the contact print I managed to make, but the world of enlargement beckons!

Any help would be greatly appreciated...

-- Stephen Gregory (smg@netcom.ca), January 25, 2001

Answers

That big black lever you found behind the lens board assembly is the answer to your plight. Pushed to one side, it locks the assembly to the rails. Pushed to the other side, it releases the assembly and allows the lens to be slid up or down the second track you mention. If releasing the big black lever doesn't work, then something is amiss with the enlarger and repair is necessary.

-- Ken Burns (kenburns@twave.net), January 25, 2001.

Ken: I remember pushing that lever back and forth--it seemed to be swinging too freely to be locking or unlocking anything. I will go back and try again, now that I know what it is supposed to do. The enlarger looks like it is in good shape, and maybe the carriage just needs a little...persuasion to get it to start moving. Should it slide freely once the lever unlocks it? Is there supposed to be much tension in the lever?

Thanks.

-- Stephen Gregory (smg@netcom.ca), January 25, 2001.


Once the lever is unlocked, the lens assembly should slide up and down the rails with no problem. As a matter of fact, once the lever is moved to unlocked position, the lens assembly should crash to the bottom of the rails if you don't catch it first. Maybe the rails are rusty. Or maybe the set screw that attaches the lever to the shaft its mounted on has come loose. Or maybe the locking mechanism is jammed.

-- Ken Burns (kenburns@twave.net), January 25, 2001.

One other thing. I'm not sure exactly how the locking mechanism is configured, but I suspect some sort of cam or shaft that is forced against the rails. The lever usually has to be turned only about a quarter turn or less to lock it down. You just move the lever until it feels snug. Maybe someone locked it down too snugly and broke the mechanism. I have also seen some older enlargers where the locking mechanism had become so worn that it would no longer lock at all.

-- Ken Burns (kenburns@twave.net), January 25, 2001.

One thing that I might mention. A 135 lens must be mounted on a cone that extends the lens down several inches from the bellows. If it is mounted in a flat lens board you will never get it to focus.

-- Jeff White (jeff@jeffsphotos.com), January 25, 2001.


The lever is locked in the left position. Swing it to the right to unlock it. These can be sticky/tricky sometimes.

A lens cone will be needed if its a D2 enlarger (but I dont think they had that lever), but if its a D5 or D6 it should have enough bellows without a cone.

-- Wayne (wsteffen@skypoint.com), January 28, 2001.


Eureka! (Well, it wasn't quite that dramatic.) Movng the carriage solved all my problems with focussing the enlarger. (The focus of the negatives is another issue entirely.) The locking knob seems to be broken, but the carriage tracks have enough friction that it stays put once it is adjusted.

Thanks for your generous help!

-- stephen gregory (smg@netcom.ca), January 31, 2001.


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