Adjusting 8 x 10 Elwood Autofocus

[Paul Glaeseman]

The 8 x 10 Elwood enlarger I just acquired has the autofocus mechanism set for the 10 inch lens with which it orginally came.

I would like to readjust the autofocus for a 12 inch (300 mm) lens. On the right side of the enlarger there is a slotted screw in the center of a circle, and a second screw at the 4 o'clock position, which I suspect are involved.

Would a member be kind enough to walk me through the sequence of steps to make this adjustment?
Thanks, Paul

[Pawlowski6132]

If you ever have the time, I'd love to see pictures of this mechanism. I have an 8x10 enlarger and focusing it is redicuous. You need arms five feet long. But these things are about 75 years old. I can't imagine what an autofocus feature would like like or even how it would work.

[Paul Glaeseman]

In the left view of the Elwood 8 x 10 Autofocus, the handcrank (A) turns the cam (B), which operates
lever (C), attached to threaded bolt (D), which lowers / raises the bellows, thus focusing the lens.

In the right view, there are slotted screws, (A) and (B) which might adjust the cam for different length lenses.

The enlarger is shown in the May, 1953 Photography Directory Issue magazine.

Needless to say, I would kill for a photocopy of the enlarger manual.

Thanks for your interest, Paul

[ic-racer]

I have never used that enlarger, but I'm pretty familiar with other autofocus enlargers.

I'd try taking the 4 screws off that plate and see what those 2 screws do near the cam.

Personally, I'd keep on this topic until I had it working. I can say from a few years of experience that focusing an 8x10 enalrger at the usual low magnification ratios causes large changes in image size. It can take a few minutes to zero in on the correct focus and image size and it is very tedious as changing the head height or focus causes the other to change. A working autofocus system should be very useful.

[Pawlowski6132]

I think I have the manual.

[jose angel]

I have an 5x7" autofocus MPP, the system looks a bit different from yours, maybe I`m missing something.
On mine, the cams are placed along the enlarger rail, three cams for three different lenses; 105, 150, 180, all the cams personalized for each lens (serial number is included, -I don`t have that lenses-). Basically the same design Linhof use on their Technika cameras, translated to an enlarger. The "cam" lenght and shape are quite different between them.
I wonder if you need a cam part, if not "personalized", at least cutted for the focal lenght you plan to use.
If not, (still wondering), the autofocus mechanism will not work properly; not a problem at all. If you have enough bellows for a longer lens maybe you can solve the problem with a raised lensboard. It seems to me a solution, but the enlarger will loose its AF properties. (The printing size will be limited, too).
(Actually, I had been on the same boat trying to use a 210mm lens with my 180 cam; I gave it up for the difficulties of "shaping" a 210mm cam. I then bought the best 180mm enlarging lens, and the enlarger works quite fine; no need of a longer lens).

[Paul Glaeseman]

Pawlowski6132: If you have the manual, I'd be very grateful for a copy.

Please contact me: thefarmme@prexar.com Thankyou, Paul

[Pawlowski6132]

Found the manual but, nuttin about the auto focus thingy. Still want?

[Paul Glaeseman]

Pawlowski6132: Thanks, just the same.

Jose Angel had the right assessment of the situation. On closer inspection, the cam is dedicated to a specific length lens. An Elwood catalog from the late 40's or early 50's may have shown optional cams available for alternative lens.

Adding a 4 inch extension to the threaded bolt (D) puts the 300mm lens in approximate range, and with the rack and pinion mechanism, I'm able to manually fine focus.

My sincere appreciation to those of you who offered help. Were anyone to run across an Elwood 8 x 10manual which discusses the autofocus, I'd like a copy: thefarmme@prexar.com

[ic-racer]

Pawlowski6132: Thanks, just the same.

Jose Angel had the right assessment of the situation. On closer inspection, the cam is dedicated to a specific length lens. An Elwood catalog from the late 40's or early 50's may have shown optional cams available for alternative lens.

Adding a 4 inch extension to the threaded bolt (D) puts the 300mm lens in approximate range, and with the rack and pinion mechanism, I'm able to manually fine focus.

My sincere appreciation to those of you who offered help. Were anyone to run across an Elwood 8 x 10manual which discusses the autofocus, I'd like a copy: thefarmme@prexar.com

Quite a few people on the forum here use a 240mm or 250mm (about 10") enlarging lens for 8x10 due to low ceiling. Is there some reason you want to go with the longer lens?

[Paul Glaeseman]

I bought the enlarger (which came without a lens), in part, because I had a pristine 300mm Rodenstock APO sitting idle on the shelf for the past 10 years. For more than ocassional printing, switching to a shorter lens would be smart.

[Chuck Pere]

This is all I have. 1940 catalog. My instruction book is only for the C2 not auto focus model.