Lens Hacking EXTREME!

Sonnar Brian

Product of the Fifties
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Quite a while ago, Roland put up a Canon 50/1.2 Parts lens for dirt cheap. It took me almost two years to find a suitable parts donor for cheap. The Ebay seller represented it quite honostly as in "no amount of force will get the focus or aperture ring to turn". Ran about $70. When I got it, I realized the front element was gone, the lens had been essentially welded in place, and was used for some special purpose. Closed down, it was actually in focus. All I needed was the rear group. Went to unscrew it. Went out and bought a dremel. Broke two cutting wheels getting that sucker out. Needed to add a 0.1mm shim to the existing 0.5mm shim, lens works great. Especially for $90.

I don't think the left over parts will go for very much.
 

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Surely there must be a Wiki entry for the word "Sweenification" :D

You are truly ambitious and know your stuff Brian!!

Cheers
Dave
 
I am humbled.

Once, in the spirit of "Zen and the Art of Motorcycle Maintenance," I created a shim for my 135/3.5 Nikkor out of cardboard. But, to paraphrase Mr. Spock from Star Trek, You are to me as I am to the amoeba.
 
Very cool Brian. Do you have a way of collimating the lens or do you take photos until everything looks right?
Thanks,
Mike
 
I bought on odd looking device off of Ebay, for $15 or so. I was the only bidder.

It is a Field-Previewer for LTM lenses. A 39mm mount, ground glass where the film would be, and a variable diopter magnifier. I use a Canon IIf to get the distance to a test target, then put the lens on the field previewer. Shim it until the actual focus agrees with the distance scale, as measured using the IIf. I've done this for the last 15 or so J-3's that went out shimmed for Leica's.
 
I am one of the lucky owners of a Sweeneyfied J3 lens, and would like to take this opportunity to publically welcome Brian back!

Please PM me your mailing address Brian, I've got a chrome '66 J12 with a crocked rear element group for you to play with or use for parts.
 
Frank: Sent a PM.

AIRDS: Just checked the aperture mechanism. After a little Ronsonol, the blades actually move. These are specific to the Canon 50mm F1.2 RF lens. PM me if that is what you are after.

AND! Just when you thought it could not get more wierd!

Remember the Canon 50mm F1.5 that Frank picked up without a rear module!. Long story, starting with Frank picking up a Canon 50 F1.5 without a rear module. I traded a 9cm F4 Elmar for it. Joe gave a heads up on a parts Canon 50/1.5 that I picked up for $67. I also had a complete 50/1.5. Made two "best" lenses out of the complete lens, butt-less lens, and parts lens. Joe cried publicly until I traded him a complete lens.

So that left me with a complete lens and one with no butt, a damaged RF coupling (dent), and busted-up mount. The helical did not stay put. Found screws from an Olympus RD fit the Canon helical, it stays in place. Used copper tape over the damaged portion (dent) up the RF coupling. AND used the rear module of a Jupiter-3. Spent a while positioning the rear element and changing the shim to get 6ft and 15ft to agree with the distance scale. The RF coupling is good. More than likely, the center will be in focus with all sorts of aberrations on the edge. Might be a good portrait lens, might be a paperweight. I'll know when I get the roll back.

But I did put the LTM to F adapter on my Nikon E3. At least it will produce some image!
 

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After reading many such posts in the past and recently becoming the owner of one of Brian's "Sweeneyfied" J3's I, too, am glad to see him back posting on the forum. You don't know me, Brian, but I do appreciate your work. Welcome back!

-Randy
 
Thankyou, Randy. The J-3 is a great lens. I keep one on the Canon IIf. It is sharp, and compares well with the Zeiss, Canon, and Nikkor "Sonnar" formula lenses. I've compared each on the same roll of film.
 
Yeah, it was the combination of lens speed and Sonnar look that I was after. Roland (ferider) got me hooked on the Sonnar look and I've been very happy with the J3 I bought from another rff member. I would be interested to see any of the test shots you've done in the past if you still have any handy.

-Randy
 
Good work, Brian! And good to see you back.

Keep me in mind if you find another rear group; I still have the 50/1.2 with the fungus-etched rear doublet.
 
Hi Brian - welcome back: missed your useful posts and advice...

Talking of which, have you any thoughts on removing the front element of my old Elmar 50/2.8?

See http://www.rangefinderforum.com/forums/showthread.php?t=32844

I could dismantle part of the lens, but came up against a ring that won't budge (not sure whether it's threaded or an interference fit - possibly the latter owing to the lock screw).

Anyway, if you have any suggestions, would you be kind enough to post them in my old thread?
 
Do you think the folks in Brian's neighborhood are worried about what my crawl out of his basement after a thunder storm? :D
 
I cleaned a Canon Elmar copy with such a ring in it. I can't state the two are the same. After removing the retaining screw, the tube came out by shoving a rubber cork into it and then turning the tube until it came out.
 
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