Versalab Parallel - quick one - help please!

[gamincurieux]

Hi........ I've just got a quick query about the use of this that I hope somebody can answer.

I just picked up a very used Leitz Focomat V35, and the Versalab Parallel is telling me that it's a little out of alignment. I'm not about to go pulling the thing apart, because that is what it would take to align this enlarger, so I am going to shim the easel up a notch here & there (which is fine as I only ever print full-frame at 16x20, both the easel & enlarger head height never get moved).

Checking both neg carrier stage & lens alignment gives differing results. Which is more important to be aligned? I would have thought that as long as the lens is aligned it shouldn't matter about the neg carrier.... am I right?

 

[Mark Fisher]

I used to have a V35 and I shimmed it under the mounting base to get the lens aligned and used some tape under the carrier to get the carrier aligned. It really wan't that hard. The problem with doing the easel is that you need to deal with both horizontal and vertical images

 

[gamincurieux]

Thanks Mark..... embarrassed to say I didn't think of that, vertical/horizontal! Yes you're right, the easel would have to move a bit there. I got so lost in thinking I'd found my solution!! Plus, it's been a short while since I last printed & vertical images are few/far between.
So, you're saying loosen the bolts underneath and put shims in between the white baseboard and the black column base?
What did you use for shims?
Pardon my ignorance, but I've not done this before. To do the easel as mentioned I was improvising with these thin stick-on rubber pieces I found here in a drawer. No doubt you're talking about something more substantial.
And, I guess I still have to ask the original question - what does the carrier matter as long as the lens is aligned?

 

[ROL]

Fiirst, make certain the parallel tool is operating correctly and not out of alignment itself, per user manual. I always align the neg. carrier first. Everything else takes a back seat to making sure the negative is parallel to the printing surface (baseboard, easel, whatever). Attempting to align the lens to the printing surface can be an inexact and frustrating exercise, depending on the enlarger and lens design.

 

[ic-racer]

Which is more important to be aligned? I would have thought that as long as the lens is aligned it shouldn't matter about the neg carrier.... am I right?

The lens axis and negative have to be perpendicular. The baseboard alignment is secondary. At very big magnifications (16x20 etc) the baseboard can be an inch off and it will still be fine, however, the negative to lens alignment needs to be nearly as accurate as that of a 35mm camera body.

This may also help: (there was a url link here which no longer exists)

 

[gamincurieux]

The neg carrier is fine, almost spot-on....... it's the lens that is way out.

Now I'm stumped...

 

[gamincurieux]

Measuring the lens involves fixing the glass with the rubber bands to the front of the lens..... just how accurate is that? That's just measuring the alignment of the plastic at the front of the lens, not the lens optical alignment! I'm not convinced, there must be another way. (by the way, it's a Schneider lens, not a Focotar)

 

[Mark Fisher]

For shims, I used some washers and a cut up soda can. Rubber is not a good choice. When I align, I align to the lens board rather than the end of the lens. I figure that the lens company could care less how perpendicular the lens axis is to the end of the lens, but they really care about how perpendicular the lens flange is. That means you should really make sure the lens board is parallel to the carrier rather than the end of the lens. I shim the carrier or the lens board (depends on enlarger which is easier....lens board preferred since it moves less often) then align the head to the baseboard.

 

[ic-racer]

Measuring the lens involves fixing the glass with the rubber bands to the front of the lens..... just how accurate is that? That's just measuring the alignment of the plastic at the front of the lens, not the lens optical alignment! I'm not convinced, there must be another way. (by the way, it's a Schneider lens, not a Focotar)

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?

 

[gorbas]

You can always take lens out and rest reflective surface on the top of lens board. Just check that there is not burr (sp?) or other uneven stuff on it. Be sure to keep same orientation of the lens board when you mount lens on it.

 

[Christiaan Phleger]

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.

 

[gamincurieux]

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

 

[gamincurieux]

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???

 

[gamincurieux]

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!!

 

[Mark Fisher]

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.

 

[gamincurieux]

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.

 

[gamincurieux]

The Schneider APO-Componon 40mm 2.8........ wow!

 

[clay]

Exactly. The focotar is very good, but the APO-componon HM is Really something else.

The Schneider APO-Componon 40mm 2.8........ wow!