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Author Message   David_nebenzahl Tinkerer Username: David_nebenzahl Post Number: 73 Registered: 12-2009 Rating: N/A Votes: 0 Posted on Wednesday, January 20, 2010 - 10:39 pm:    Your sharpness problem is undoubtedly due to the lensboard not being parallel to the film plane, not to any helical lubrication (or lack thereof) problems. As you guessed, the focus mechanism moves the lens forward and backward linearly. You may have to bend things to bring the lensboard back into parallel; after all, this is probably how it got out of whack in the first place.