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Explore the world of vintage lenses through repair notes, real test shots, and detailed archive threads packed with images.

Explore the world of vintage lenses through repair notes, real test shots, and detailed archive threads packed with images.
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Topcor 35/2.8
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Following a successful conversion of the 100/2.8 Topcor to M42, I did the same thing to the 35/2.8. Frankly, I think these topcor lenses are excellent and the 35/2.8 is at least as good as my Flek!






patrickh


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wow. i missed your other post--who the heck is topcor? Smile nice composition on 1 and great sharpness.


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Thanks for your comment

Topcon made SLR's and accompanying lenses back in the 60's-70's. They were great innovators (first TTL metering) and their cameras were built like trucks. They were best known after a while for the 58/1.4 standard lens, which is made today (I believe) under license by Cosina. The originals go on fleabay for $300! It is deadly sharp.
The mount was a derivative of Exakta (another great innovator company). This makes them awkward to adapt, but there is a guy in China who is offering replacement M42 mounts. This is a reversible adaptation. The most common lenses from the range are all excellent - 35/2.8, 100/2.8, and 135/3.5. Any one of them can be found for well under $100. The mod costs $55 and about 10 minutes if the screws co-operate.

patrickh


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how interesting! thanks so much--you use these lenses very well indeed!


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truly impressive #1, you can feel the air!


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Well, i suppose it's time to go searchine for the seller offering the replacement M42 mounts Wink ...

Thanks for sharing the samples.

Cheers


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Hurray, maybe my fav lens. Topcor RE AUTO 35/2.8.
I love the 3d on #1.

I found at minimum focus distance, and right background, this lens produce most interesting and pleasant of swirl.
[Wide open of course].
Min focus is really short! And colors are fantastic. A great addition for the flower shooter, esp. when 100 takumar and
50 volna are not wide enough!
I find 3d awesome at f-2.8-5.6's
I still relatively new to this lens, but so far, perhaps, my fav at 35mm FL.. for close-up and normal shooting.


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That's the one Bruce. When I have some decent light to try it out (even #2 was in a mist) I shall be able to judge better, But so far so good


patrickh


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Darn, #1 is awesome, like 3D generated. I think i have few TOPCORs somewhere in the back...time to bring them to light Smile .


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hey patrick, i found this topcon converter on ebay-would eliminate the need for mount conversion i think:

http://cgi.ebay.com/Exakta-Topcon-Lens-To-Canon-EOS-EF-Mount-adapter-450D_W0QQitemZ270504081536QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3efb4cb880#ht_3042wt_988

hope its useful!
tony


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Unfortunately these adapters do not work very well - they don't lock the mount in properly. Also I have found they do not usually allow infinity focusing. I tried it and that's why I finished up doing the mount conversion. The great thing about the conversion is that it is completely reversible - nothing is destroyed or changed.


patrickh


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oh, ok, i didnt realize you had tried that route already.


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It's seems to be a great lens. Congratulations !!

Thanks for sharing.

Rino.


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Another means to convert Exakta mount to M42 is much less expensive. For $5.80 USD you can purchase a 42mm-39mm step-down ring - Click here to see on Ebay.

The greatest diameter of the base of the Exakta bayonet is 38mm. Remove the stop pin from the Exakta flange, slide the M39-M42 ring down and glue it in place. I use Gorilla Glue which expands and fills the small gap nicely. Voila! An M42 lens. It is reversible by heating the glue or using a solvent to remove it.

An example:


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The topcor mount has a small lever that controls the aperture stop down just alongside where you glued the adapter - how did you deal with that?


patrickh


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patrick,

Ah, I see the issue. The Exakta mount doesn't have that, so I didn't need to address it. I suppose I would remove the mount, remove and bag the lever, spring assembly, and surrounding ring; and then replace the mount and proceed as before with the glue. A bit more labor.


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I dont think this will fix my mirror and 5dmkII issue, as my mirror hangs up on the rear of the lens. With the m42 conversion of patrickh's the extension of the Topcor lens into the camera's body is lessened. Will this m39/m42 ring help with other exakta mount lens with the 5DmkII mirror?


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Bruce,

I don't know. I use a Nikon D40 which I converted to handle M42 mounts. I have eight Exakta lenses converted with the rings and I get infinity on all, plus one M42 lens and one T-mount > M42 with which I also get infinity (before the stop). No mirror strike on these despite coming almost 2mm closer than Nikon specs.

This doesn't say anything, though about the EOS mirror. If one Exakta is too long, I would imagine they all are. I would first measure the flange to mirror depth and then hie myself to a hardware store for some thin ring gaskets of the appropriate size and different thicknesses. Slide the gaskets on until you don't need to worry about mirror strike, then crazy-glue them together but not to the lens. Whenever you want to use an Exakta lens, slide the custom gasket onto the lens before assembly. A $1.00 solution.


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I paid attention to what you said, and found this. Topcor RE Auto 35mm f2'8

Mount Topcon, for U$S 50.- It is equal to that you have?


Last edited by francotirador on Wed Jan 06, 2010 2:53 am; edited 1 time in total


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From what I can see from this single view of this lens, it certainly looks to be the right one, the silver version as it comes in black as well. Mine is silver too.


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I have offered here for a 35/2.8 RE and want to know if your photos are sharpening? ES by whether or not a very sharp lens.
Greetings,
I decided on your photos.


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No, I only used standard sharpening, nothing extra. This lens is sharp, as is the 100/2.8 and the 135/3.5. There is no colour adjustment or other enhancement. The host site (smugmug) uses some form of sharpening algorithm to compensate for downsizing when a smaller version than full size is used, I believe



patrickh


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patrickh wrote:
No, I only used standard sharpening, nothing extra. This lens is sharp, as is the 100/2.8 and the 135/3.5. There is no colour adjustment or other enhancement. The host site (smugmug) uses some form of sharpening algorithm to compensate for downsizing when a smaller version than full size is used, I believe



patrickh
Many Thanks


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Unfortunately, the vat to buy topcor that has damaged the coating on the first elements.
The reflection on the surface appears very diffuse. I think they kept it with moisture.
It is a pity, I try to buy the Flektogon.