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  1. #11

    Join Date
    Feb 2006
    Location
    Hawaii
    Shooter
    35mm RF
    Posts
    715
    After using my Versalab for 10+ years with many lenses, I can assure you that the front ring of the enlarging lens is a good indicator of the lens elements. If that is way off, something is quite off and either the lens has been incorrectly rebuilt or there is something off on the enlarger. I have and align my Bessler MX45 and Leica Focomat 1c as well as other friends. I've also thought that the rubber band thing is not that good but after 10 years I've not thought of a better way. I actually just do a quicky check by holding the glass slide against the lens each and every time I print, my Bessler lens board mount has a small hitch and it can be slightly off when I change lenses for a format change. Last year I changed my first set of batteries BTW, and the Versalab would be the 1st thing I'd re-purchased if I lost or broke mine, works amazing for quick copy work as well.

  2. #12

    Join Date
    Jan 2009
    Location
    Melbourne, Australia
    Shooter
    35mm
    Posts
    297
    Quote Originally Posted by ic-racer View Post
    If you shine the laser into the center of the lens there will be a diffraction pattern of concentric circles that fall back on the Versalab face. The laser will be pointing parallel to the axis of the lens elements when the concentric circles form a bullseye.

    Do you have the knob that holds the focusing helicoid tightened (#17)? Is there any wiggle or change in the lens alignment when spinning the fine-focus helicoid ring (#15)? Also, ring #18 that lets the lens rotate, is that tight?
    I don't have the knob, but I'm using a screw that fits in there, have to do/undo it with a screwdriver every time, seems to do the job ok though (this screw goes in where the knob should be... I haven't lost the other screw opposite that holds the bearing in, it is still in there, I can definately feel the detente). Yes there is some wiggle/change in the lens alignment whenever I touch just about anything in that general area!

    So, over the last day or so I got underneath it & shimmed it up a bit, getting it to just about bulls-eye on the laser. I'm happy with that. I've also found a nice (& cheap 2nd-hand Schneider APO-Componon 40mm 2.8, just waiting on it to arrive from the US. Aaaand, I ordered from Leica a brand new later-version light mixing box (still available!), so hopefully that will light the corners up so I can see what's going on there. When that's all here & together I'll be checking alignment again... new WA lens, head brought way down, corners hopefully sharper & better lit, that could all improve matters, or put alignment completely out of whack again!! I don't want to obsess too much... I just want to correct it & then crack on with some printing.

    Thanks very much for your advice everyone, I really do appreciate it
    Last edited by gamincurieux; 01-07-2012 at 01:00 PM. Click to view previous post history. Reason: bad spelling!!

  3. #13

    Join Date
    Jan 2009
    Location
    Melbourne, Australia
    Shooter
    35mm
    Posts
    297
    OK, I've had to redo the shims as I'd really stuffed far too much in there & I had the screws underneath done up so tight that I felt the column would shoot off into the ceiling if it was done up any tighter, I could see the baseboard starting to curl, I swear..... indeed one of the bolts has been totally burred inside so the allen key won't work & can't be removed.... so, I've redone it as best I can, all things considered, conservatively doing up the 3 remaining adjustable bolts this time, and I have the red dot showing just 1 or maybe 2mm off from dead-centre target........... I mean, that's not bad, is it???

  4. #14

    Join Date
    Jan 2009
    Location
    Melbourne, Australia
    Shooter
    35mm
    Posts
    297
    I just can't do any printing just yet to test...... but that's not bad... is it?

    It was much worse before I started!!

  5. #15
    Mark Fisher's Avatar
    Join Date
    Dec 2003
    Location
    Chicago
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    Medium Format
    Posts
    1,627
    Images
    151
    It is probably fine. As others have said, the carrier to lens flange is the critical data.

    BTW-speaking as a very old....errrr.....I mean experienced mechanical engineer/product designer, I decided to stop using the top of the lens for alignment and use the lens mounting are instead. The reason is that in the design of the lens, a critical dimension for the performance is the perpendicularity of the lens axis (and thus lens mount) to the lens board. They could care less about the end of the lens and probably don't control it nearly as well since it has no effect on the performance of the lens. Controlling any dimension that doesn't add to performance is a waste of money. I checked this theory with a Leitz (modern 40mm) lens and a Schneider and the ends were a fair amount off compared to the base. Is it enough to make a difference...I have no idea....but I figured I might as well measure of the lens board mount since I could.

  6. #16

    Join Date
    Jan 2009
    Location
    Melbourne, Australia
    Shooter
    35mm
    Posts
    297
    And there's the challenge - how to measure off the lensboard on a Leitz V35?

    I'm not in front of it at the moment to look, but I'm having trouble imagining how...... maybe if I could get a small round piece/disc of glass, put double-sided tape on one side, take the lens out then get the glass disc up in that space somehow, stick it on up there on the lens mount........ worth a try.

  7. #17

    Join Date
    Jan 2009
    Location
    Melbourne, Australia
    Shooter
    35mm
    Posts
    297
    The Schneider APO-Componon 40mm 2.8........ wow!

  8. #18
    clay's Avatar
    Join Date
    Nov 2002
    Location
    Asheville, North Carolina
    Shooter
    Multi Format
    Posts
    1,118
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    8
    Exactly. The focotar is very good, but the APO-componon HM is Really something else.

    Quote Originally Posted by gamincurieux View Post
    The Schneider APO-Componon 40mm 2.8........ wow!
    I just want to feel nostalgic like I used to.


    http://www.clayharmon.net - turnip extraordinaire

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