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Mark Sawyer
24-May-2007, 17:26
I recently bought a Dallmeyer 3b lens, and I'm unsure about the soft focus adjustment. As you can see in the photo, the barrel has an arrow and the instruction "turn for soft focus". However, nothing will turn unless a small screw is removed from the bottom of the barrel allowing the barrel to be unscrewed from the rear elements. I don't know if that's how it's meant to turn, but I doubt it...

Near the rear of the lens, there is a small band with another arrow pointing down the lens barrel. The band doesn't turn, and has nothing to grip to make it turn, so I don't know whether that's the adjustment or not.

The 1931 Dallmeyer instructions at cameraeccentric.com aren't very specific.

Anybody got a B series Dallmeyer and know what is supposed to turn? Thanks muchly!

Jason Greenberg Motamedi
24-May-2007, 18:31
Mark, the threads on your lens's defocus adjustment are probably frozen.

There were two non-focusing barrel styles; the earlier version (pre-1900 or so) where you had to reach into the back of the camera and turn the rear element, and your version where one would simply rotate the barrel (with that screw in its place) while mount and flange remain in place. The numbers or notches indicate how much defocus you have used.

So, theoretically you should be able to grab the barrel while it is mounted on camera and twist to get defocus. However, I have seen about eight or nine of these later non-focusing lenses and not a single one worked properly. If you can get the glass out you could try penetrating oil. If not I would just leave it be. The defocus on the Dallmeyer Patent Portrait lenses doesn't really do all that much; you won't get anything close to Verito-type glowing highlights. Rather, everything will just be dull, like a poor quality lens.

Mark Sawyer
24-May-2007, 22:09
Thank you for the reply, Jason!

hmmmm... I have a graphite in a penetrating base solution. I might try that. But I can't get the rear element out. I don't think lubricating it would hurt the uncoated glass...

"The numbers or notches indicate how much defocus you have used."

No numbers or notches are there, just an arrow on that narrow band with nothing to line it up with. As you suggested, I may have to just use it as-is. But it would be nice to see what it did at different settings, or at least know whether it was set to full-sharpness or full-softness...

Jason Greenberg Motamedi
24-May-2007, 22:37
Mark,

I just ran down and took a look at my 1910 3B, and sure enough, there are no numbers. The earlier models with the adjustment from the rear had I through IV marked, but apparently the more recent ones don't. Mine is at zero when the little arrow lines up between the F and the T in SOFT (As in "TURN FOR SOFT FOCUS"). Looking at yours, it seems a bit clockwise from mine, but perhaps still at zero.

I guess you just have to eyeball it; in general with the other models the softest is a 180 degree rotation, so I assume the same goes with these.

Hope this helps.

russyoung
26-May-2007, 06:31
Mark-

If misery loves company--- I have two frozen ones. Even with penetrating oil. have never been able to loosen them. If you find a method, PLEASE share!

Did you do uranotypes about 1980?

Russ Young

Mark Sawyer
26-May-2007, 10:30
I've been letting a few doses of graphite in a light penetrating base ("Lock-Ease", made for sticky/frozen locks) soak in for a couple of days; no luck yet. I need to pick up a couple of those rubber gripping mattes like they use for jar lids and really lay into it. But if that doesn't work, I guess I have just another Petzval, albeit a cool looking one. I was hoping for something similar to a Verito effect, but from Jason's experience, that doesn't sound like it would happen anyways...

Yes, that was me doing uranium prints back in the early 80's. It was a very slow process (one day exposures under the Arizona sun!), but I liked the prints:

Jason Greenberg Motamedi
26-May-2007, 11:02
Try two strap wenches with rubber straps. I have a few huge ones I use for taking apart these lenses. They work much better than those stupid rubber grips.

I LOVE the uranotypes. I saw some that Blake Ferris made and I have been dying to give it a try. I am sure my family will just love having one more toxic salt in the house.

Jon Wilson
27-May-2007, 20:27
I don't know if this product will work to unfreeze your lens, but I have a brass dallmeyer and the rear cell was frozen tight. I used a couple small drops of Rust Buster and it is no longer frozen. I had tried the rubber straps etc., but never had any luck.....I tried this product and with minimal force of gripping the barrel and a rubber lid opener....the lens was no longer frozen and none of the chemical touched the glass. I found this product at an electrical supply shop. It cost about $6.00 for a 4 oz bottle. It is manufactured by Johnstone Supply, Portland, OR.
Good luck. Jon

Mark Sawyer
28-May-2007, 10:24
Jon~ thanks for the tip. I'll look for some tomorrow when I'm out. The lens is on a board now and ready to go otherwise...

Jason~ Thank you! I really liked the uranium prints. I still have some uranium nitrate around and may try it again someday. It's not very radioactive, but yep, pretty toxic!