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RE Auto-Topcor Mount
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PostPosted: Sat Jul 27, 2019 11:44 pm    Post subject: RE Auto-Topcor Mount Reply with quote

Hello. My name is Sebastian. I am an adapted lens addict. I have lurked here for along time and tried to fight my addiction but I have lost. So now I have joined this forum and accepted my condition. Luckily old lenses are cheap and don't take up much space.

Anyways, I recently purchased a RE. Auto-Topcor 13,5cm lens. I did some quick searching, but it's not clear to me what mount is used. K&F website says topcor mount. Can someone guide me what adapter I would need to mount this lens to a Fuji X-mount camera (X-T1).


PostPosted: Sun Jul 28, 2019 12:17 am    Post subject: Reply with quote

Welcome Sebastian!

Re.Topcor lenses have the same mount as Exakta. So you may get one cheap to start with.

Please share your shots and experiments, make visible your observations and questions. This way you will contribute to the precious and diversified knowledge base this forum is. And you will see how gentle are expert members here.


PostPosted: Sun Jul 28, 2019 12:44 am    Post subject: Reply with quote

Cheap simple adapter will set you back under 15 dollars delivered. For your camera you can likely get a helical adapter. They are a bit more but allow you to focus close.


PostPosted: Sun Jul 28, 2019 10:22 am    Post subject: Reply with quote

Welcome Sebastian.


PostPosted: Sun Jul 28, 2019 1:12 pm    Post subject: Re: RE Auto-Topcor Mount Reply with quote

cbass wrote:
Hello. My name is Sebastian. I am an adapted lens addict. I have lurked here for along time and tried to fight my addiction but I have lost. So now I have joined this forum and accepted my condition. Luckily old lenses are cheap and don't take up much space.

Anyways, I recently purchased a RE. Auto-Topcor 13,5cm lens. I did some quick searching, but it's not clear to me what mount is used. K&F website says topcor mount. Can someone guide me what adapter I would need to mount this lens to a Fuji X-mount camera (X-T1).

Hello, as others mentioned, Topcor RE cameras feature a modified (to allow open-aperture TTL metering) Exakta bayonet mount. Note that adapter manufacturers often label these Exakta/Topcor RE adapters simply as "EXA". So search for a "EXA to Fuji X" adapter.


PostPosted: Sun Jul 28, 2019 8:20 pm    Post subject: Reply with quote

Thank you. That is what i need to know.


PostPosted: Sun Jul 28, 2019 8:45 pm    Post subject: Reply with quote

Welcome to the forum, Sebastien,

Here is what one of the simple adapters looks like:



PostPosted: Tue Jul 30, 2019 7:31 pm    Post subject: Reply with quote

I have one more question. Looks like these lenses are from the 1960s and 1970s. They appear to come with rubber. I am going to assume this rubber will degrade as time goes on if not already. Is there replacement rubber you can buy? Is there some way to restore/preserve the rubber?


PostPosted: Tue Jul 30, 2019 7:48 pm    Post subject: Reply with quote

If you look at the secondary market, you'll find many more lenses with perfectly conserved rubber than with degraded or missing one. This is due to vulcanization invented back in the late XIX century: the rubber is "tempered" and does not easily degrade under moderate use. While recommended shelf life of rubber products vary from 5 to 20 years, the really visible degradation normally starts being visible long after. As long as we touch our lenses gently and normally do not bring them to Sahara or Siberia, I think we have at least another 30 years until the issue manifests itself in a massive way.


PostPosted: Tue Jul 30, 2019 10:24 pm    Post subject: Reply with quote

I'm not 100% sure about this, but I think the early Topcor lenses with rubber seem to be worse off than the later ones, it could be a function of a number of things during the vulcanization process like temperature & duration.


PostPosted: Wed Jul 31, 2019 3:00 am    Post subject: Reply with quote

From my personal experience with some Exakta adapters that see heavy lens rotation.

I have two Fotodiox Pro and one Fotasy; all are Exakta to Nex.

Exakta is funny, because it has a release lever which, I think, is the weak link to the system. It can be accidently disengaged when you reach to focus or just wear out.

The Fotasy never locked onto my Topcor lenses in a reliable fashion, but did safely work with other brands of Exakta mount lenses. It has something to do with the shape of the tooth that receives the locking pin on the lens. The lever on the fotasy broke after a not much use, right where the lever meets the locking pin. It was also a very tight fit. Maybe if I ordered two the other would have been fine.

I will only use Fotodiox Pro for my very best Topcor lenses, because I can trust them so far.

I also have two Exakta mount lenses that have been convered to M42, and that seems to be the most versatile route.


PostPosted: Wed Jul 31, 2019 3:50 am    Post subject: Reply with quote

I live in Arizona. If it isn't stone or dirt it's going to disintegrate soon enough.

Even then, let's say the lens was made in 1965 that makes it a 54 year old lens.
Even the lenses that look mint, unused with perfect glass and minimal dust if you look
closely you can see tiny cracks starting to develop in the rubber even if it looks good overall.


PostPosted: Wed Jul 31, 2019 9:30 am    Post subject: Reply with quote

cbass wrote:
I live in Arizona. If it isn't stone or dirt it's going to disintegrate soon enough.

Even then, let's say the lens was made in 1965 that makes it a 54 year old lens.
Even the lenses that look mint, unused with perfect glass and minimal dust if you look
closely you can see tiny cracks starting to develop in the rubber even if it looks good overall.


I have the same problem, especially with elder Mamiya lenses (XTL series) and some Canon FL lenses.

To repair such a lens you can carefully glue the parts back on the metal using e. g. "Pattex Repair Gel Extreme" (or a similar product). It's also possible to correct an overstretched rubber grip using the same kind of glue. To keep the rubber grip parts in the correct position I do apply a stretchy duct tape just after gluing.

Stephan


PostPosted: Wed Jul 31, 2019 12:48 pm    Post subject: Reply with quote

The best kept rubber parts were from lenses that were not stored in duration being exposed to oxidation like humidity, water and fresh air. For the most part oils from the skin can cause the rubber to swell and degrade. UV will cause dry rot and accelerate the process.

Topcor lenses are known to have stiff focusing from bad lube. The excess torque to focus will cause the rubber to stretch like others have mentioned.

If you want the rubber to last don't use it with greasy hands, store it somewhere away from UV and the open elements.

Modern lenses more than likely use TPU.

I don't consider the loss of a rubber grip in any way a degradation of the value of a lens. I suppose the lens supplier knew that the rubber wasn't going to last, and probably made available replacements especially in light of internal repairs that needed to remove the grip.

The old rubber is just going to get everywhere on your hands and shirt and maybe even the important parts of the camera. If it is crumbly then just remove all the old rubber. Again this is my personal opinion.


PostPosted: Thu Aug 01, 2019 11:08 pm    Post subject: Reply with quote

Reading your comments, fellows, I ask myself if I was not too optimistic. Saying that, I acknowledge to have had rubber issues among the rarest ones as compared to stiff focus, fungus, oily aperture and some other mechanic troubles.


PostPosted: Fri Aug 02, 2019 4:18 pm    Post subject: Reply with quote

I use Armor-All leather protectant. It returns some of the softening agents to the rubber. It is also useful on plastic parts to prevent drying and cracking. As indicated light and heat are the main enemies. So like the Traveling Wilbury's song store it a cool dark place. Original type replacement will be near impossible. A nice looking substitute is a pebble grain leather or good quality vinyl. Measure very carefully and install with contact cement,


PostPosted: Fri Aug 02, 2019 5:21 pm    Post subject: Reply with quote

I found a replacement. It just costs more than I paid for the lens.

https://www.adorama.com/cg1401.html?utm_medium=cpc&utm_source=adl-gbase

Also. I have read that some RE Auto Topcors will not fit Exackta adapters?
You may have to trim a pin. What pin? Is this only on some Topcors?


PostPosted: Sat Aug 03, 2019 7:26 pm    Post subject: Reply with quote

cbass wrote:
I found a replacement. It just costs more than I paid for the lens.

https://www.adorama.com/cg1401.html?utm_medium=cpc&utm_source=adl-gbase

This grip is too aggressive, like gear teeth, the real ones are much smoother.
Quote:
Also. I have read that some RE Auto Topcors will not fit Exackta adapters?
You may have to trim a pin. What pin? Is this only on some Topcors?

RE lenses have extra pins for communicating to the camera it's aperture position on the outside, and to auto stop-down the aperture when you take the exposure.


Both of my adapters fit just fine on both my Exakta and Topcor lenses(R & RE), I should note that RE lenses don't mount on R bodies for this reason, F-Auto lenses too.



Blazer0ne wrote:
Exakta is funny, because it has a release lever which, I think, is the weak link to the system. It can be accidently disengaged when you reach to focus or just wear out.

I have 2 adapters, one with a long lever that is quite easy to unlock:


And one(adapter brand is Big_is, prior to his abandoning adapters, but this looks like it) with a shorter lever that doesn't stick out as much, it takes 3x the effort to unlock the mount(the lever doesn't protrude from the body) and looks great on the RE's:


Quote:
The Fotasy never locked onto my Topcor lenses in a reliable fashion, but did safely work with other brands of Exakta mount lenses. It has something to do with the shape of the tooth that receives the locking pin on the lens. The lever on the fotasy broke after a not much use, right where the lever meets the locking pin. It was also a very tight fit. Maybe if I ordered two the other would have been fine.

I will only use Fotodiox Pro for my very best Topcor lenses, because I can trust them so far.

I don't mind it, it's far more robust than Konica F(what were they thinking?).
Anyways, it looks like your lever was made from aluminum and not chrome plated brass/steel like mine appears to be.


PostPosted: Tue Aug 20, 2019 5:54 pm    Post subject: Reply with quote

So I have my Topcor to Fuji adapter. However, I want to try this lens on my speed booster which has a Canon EF mount. Does anyone have a suggestion for a EXA to EF adapter? I see two kinds. One is a slim piece of metal. The other is a larger adapter that appears to have a glass element in it. The slim adapter also has two variations. One with a single long slot. Another with two long slots.


PostPosted: Thu Aug 22, 2019 2:20 am    Post subject: Reply with quote

I didn't see any on eBay other than the standard Exakta to EF adapters, they don't have an outer groove like in this thread.
http://forum.mflenses.com/exakta-to-eos-adapter-from-alex-t19643.html


PostPosted: Thu Aug 22, 2019 2:56 am    Post subject: Reply with quote

From the slim adapters I see this one:



and this one:



None look like in the thread you posted.


PostPosted: Thu Aug 22, 2019 2:43 pm    Post subject: Reply with quote

Exa and exakta use the same mount. Exa was Ihagee's lower tier camera. They use all the same lenses. There must be a half dozen Exakta to EOS (EF) adapters to choose from via dozens of ebay venodors.


PostPosted: Thu Aug 22, 2019 5:19 pm    Post subject: Reply with quote

It's not so simple as just grabbing any Exakta adapter. Auto Topcor lensese are a modified Exakta mount. I looked at the lens and the previous post pointed to the adapter I think I need. It needs to have a outer channel. If it doesn't, then I will need to file parts off the lens.


PostPosted: Thu Aug 22, 2019 5:44 pm    Post subject: Reply with quote

This is true. Topcon mounted to the same bayonet style. That is, diameter and bayonet lugs are the same. But pins and connections and so forth are different. The pins in the base of the Topcon are generally tiny screw in posts which usually can be removed with a very tiny screwdriver (be sure to save and mark where the came from if you ever intend to sell the lens!)


PostPosted: Thu Aug 22, 2019 7:18 pm    Post subject: Reply with quote

Those screws are the least of my worries. The outer slot is important because as you move the aperture ring there is a pin that moves. I think I finally found the adapter that I need. It says it's not for Full Frame canon camera's but APS-C, which is fine with me as the plan is to mount it to a lens turbo ii speed booster. Hopefully the speed booster glass elements are deep enough that the mount doesn't hit the glass. Here is the adapter I found. I think this is the one.