PDA

View Full Version : Using a Dallmeyer ADON zoom telephoto lens



john wilton
29-Jul-2011, 12:21
Does anyone have the instructions for this lens? The iris is marked in geometric numbers (1,2,4,8,16,32). There is a table (attached) which shoes the max f stop ranging from 10 at minimum magnification to 32 at highest magnification. I have seen reference to a "Dallmeyer calculator".

There are ads for the lens in the catalogs on cameraeccentic, but no instructions. Does anyone have the instruction booklet, or have experience with the lens and can give me some tips on how to figure the aperture?

Richard Rankin
29-Jul-2011, 15:14
I have a photocopied manual for ' The "Adon" Telephoto Lens' from Ross, Ltd Opticians. There are several variations of Adon and I don't know which one it is for. It has some instructions for use in conjunction with an ordinary lens and photo examples of the Adon used alone. I don't think my copy has all the pages, though. It's is too light for my crappy scanner to scan but I could mail it to you and you can read/scan/copy and return it. Not sure how useful it is but it might be better than nothing.
Richard

john wilton
29-Jul-2011, 18:13
Thanks Richard, but I'm afraid the instructions wouldn't apply to me because mine is the stand-alone lens type.

Phil
2-Aug-2011, 19:24
This may help:

Dan Fromm
2-Aug-2011, 22:09
John, the VM says (my paragraphing, the VM has just one block of text):

Adon Adjustable Tele was still made in 1936, some 43 years after the launch. Normally it had a 4.5in front lens and -2.25in rear lens for 12-50in overall focus. It gave about 3x magnification, ie focus relative to extension. The -1in alternative rear lens seems scarce, and gave about 4x magnifications. It was then sold
with a Luc shutter if requested.(T.B,1/25sec).

In use, measure the film-to -flange distance and multiply by 2.5 to get the focal length in use. The maximum aperture is 1.2in or 30mm. Divide the focal length by the aperture to get the f number, using the same units for both. Example: for 5x4, and a 7in extension, the focal length is actually7x2.5= 18.5in.and the maximum aperture is 18.5/1.2 working in inches.

Now calculate the exposure at f15, say 1/60sec, and finally multiply this by the number on the iris scale used. These numbers are 1-8, and at say No4, the exposure would be 1/15sec.( Or use a ttl meter!).

They can be used with formats from below 6x9cm up to 15x12in, but do not cover a very wide angle.

john wilton
7-Aug-2011, 13:13
Thanks Phil and Dan, this gives me the info I need. Now I know the numbers on the iris scale are multiplication factors. One anomaly: With 4" flange focus (13.5" effective) the Adon gives an image of similar scale as, but much dimmer than, a 13.75 f/12.5 Protar VII cell. The glass measures 30mm across...this would give f11.5; the physical max opening of the diaphragm is more like 21mm. I guess I wiil be generous with exposure. No TTL measurement gear available.

Joe Smigiel
7-Aug-2011, 22:18
The Adon lens pictured above is for sale (http://www.largeformatphotography.info/forum/showthread.php?t=78274)on the forum if anyone is interested.

Joe

Jim C.
30-Jun-2014, 15:23
Thought I would resurrect this thread since I'm mucking around with my Adon lens, I shot a few tests,
but my gut feeling is that my focal plane shutter is adding tons of vibration at the extensions I'm using.
I'm curious if anyone mounted this lens on a existing leaf shutter without having to machine an adapter ?

cowanw
1-Jul-2014, 06:31
This is he copy on Adon that I have.

http://www.largeformatphotography.info/forum/showthread.php?39843-4x5-ZOOM-LENS-DALLMEYER-ADON-Ser-XI-12-quot-f4-5&highlight=adon
Here are two examples of comparison. This is a longer configuration and (weirdly to me ) is the shorter focal length 12 inches
117586

117587 This is the shorter configuration and is about 15 inch focal length. Calculated maximum Fstops are 4.5 for the 15" and f 3.1 for the 12 inch
As you can see the longer focal length at wide open presages the Leica glow. I like that. As a sharp lens It functions rather ordinarily, but for full functionality I would think you would need to calculate up a chart of focal lengths and f stops

Jim C.
2-Jul-2014, 06:19
Interesting shots with your Adon, cowanw, I'm not familiar with the version you have,
mine is the smaller rack and pinion focusing version pictured at the top of the post.
Is yours mounted on a shutter or did you make those shots with a FPS or the old take the lens cap off method ?

I guess no one has tried mounting the smaller rack and pinion version on a shutter ?

cowanw
2-Jul-2014, 07:12
Adon information on the web is a bit confusing.
In the excellent Camera Eccentric site
http://www.cameraeccentric.com/html/info/dallmeyer_2.html
My lens is the series XI which is described as a telephoto but not a zoom. Nevertheless it is a zoom or it is broken and the front element slides out in a perfectly controllable way to a consistent extent.
I use a Packard shutter.
I expect you will just have to use it and explore its characteristics yourself.

Jim C.
2-Jul-2014, 09:26
Yes the info on the web is a bit confusing since there are two versions I know of
and now with your link there's three, since the Adon pictured doesn't seem to have
a rack and pinion focusing, I guess that version has a helicoid focusing mech.

cowanw
2-Jul-2014, 09:56
No. just a push and pull for zoom. But that isn't really a focus mechanism, Bellows is used for that.

Jim Noel
2-Jul-2014, 13:16
I had one of these for years, long before the internet was even a dream. I found the original info card helpful, but in the end,each image was a matter of trial and error until I got what i wanted on the GG.