[snm]

Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here.

---

Hi all,

got an Orestegor 200mm f4 lens, which appears to have the Exacta mount (at least seems like that -- it is narrower than usual M42, and the mount part is detachable from the lens).

Could you advise what would be the best way to mount this lens on Pentax? I've read about difference between mounting distances when comparing M42 and Exacta mounts. When looking for an adapter, what should I be looking for? Would any Exacta to M42 or similar adapters do the job, or since the lens has detachable mounts, should I be looking for something specifically from Meyer-Optik?

[UncleVanya]

Pictures?

[snm]

Attaching the pictures:

First, bare lens with the adapter removed, second, with the existing adapter that I'm guessing is for Exakta.

[othar]

The only difference between Exacta and M42 versions of this lens is the exchangeable part in the back.
That said, the M42 version is the more convenient one, so you are more likely to find an additional Exacta mount than a M42 mount version for that lens. Therefore it is easier (and cheaper) to buy this lens with the M42 mount attached from the beginning.

If you have access to a lathe and/or a milling machine I can measure the size of the M42 mount on my lens, so you can build it yourself

[marcusBMG]

yes that looks like the exacta mount (of use only to exacta enthusiasts), this lens was supplied with either this or the M42. Unfortunately the mounts are hardly ever available seperately. Now I can't remember exactly but I think the 135m is the same, so if you find an acquire one of those with M42, you can just swap over.

Alternatively, since the mount is removable, if you have access to a lathe you could do an easy diy convert to PK (just turn down the exacta bayonet nb exacta reg distance 44mm, pk 45.45mm, drill and tap and screw the bayonet on - easier than trying for M42 actually), using a bayonet off a junk lens (best) or a M42 to PK adapter (cheap off eg ebay) to provide the bayonet.

[snm]

Thanks all. I though initially that it would be M42 when buying, but it appears the seller made the mistake. The price was lower than the shipping, and overall the quality looks very good, so not in a hurry to return yet.

Additional question, does the "bare" portion of the lens, on top of which the mounts are mounted, has some sort of known name? Maybe it's possible to find only the converters for sale? I'm just not sure what to even search for..

What about the exakta->m42 adapter rings? If I understand correctly, these will not have infinity focus, but for any other focal distance the lens would work properly?

---------- Post added 02-02-21 at 10:06 AM ----------

Another question, could maybe a Pentacon 6 converter fit the "bare" portion of the lens?

For example, would a converter like this one (Pentacon 6/Kiev 60 Lens to Pentax PK K Mount Adapter K5,K5II,K7,Kx,Kr,Pentax Q | eBay), Pentacon 6 to Pentax K work with this lens?

[othar]

Another question, could maybe a Pentacon 6 converter fit the "bare" portion of the lens?

No. As far as I know is Pentacon 6 a medium format lens mount (I think the Meyer-Optik 300/4 is available in that mount in adition to M42 mount for FF cameras - beeing a medium format lens originally, but not the Pentacon/Meyer-Optik Görlitz 200/4)

[othar]

Maybe it's possible to find only the converters for sale?

The only converter I can find are the ones for Exacta, because no one needs them for digital.
So you can either buy the whole lens with M42 mount or convert your current lens on yourself.

[D1N0]

Thanks all. I though initially that it would be M42 when buying, but it appears the seller made the mistake. The price was lower than the shipping, and overall the quality looks very good, so not in a hurry to return yet.

Additional question, does the "bare" portion of the lens, on top of which the mounts are mounted, has some sort of known name? Maybe it's possible to find only the converters for sale? I'm just not sure what to even search for..

What about the exakta->m42 adapter rings? If I understand correctly, these will not have infinity focus, but for any other focal distance the lens would work properly?

---------- Post added 02-02-21 at 10:06 AM ----------

Another question, could maybe a Pentacon 6 converter fit the "bare" portion of the lens?

For example, would a converter like this one (Pentacon 6/Kiev 60 Lens to Pentax PK K Mount Adapter K5,K5II,K7,Kx,Kr,Pentax Q | eBay), Pentacon 6 to Pentax K work with this lens?

It is just a screw mount. Pentacon six is bayonet and much longer. You could look for a junk m42 Pentacon or Meyer, but those are still over priced. I think the Pentacon 200mm is overrated. The 135mm is much better.

[stevebrot]

What about the exakta->m42 adapter rings?

Are you meaning the ring with three screw type commonly sold on eBay? They don't work.

The topic has come up fairly frequently here on Pentax Forums and the Google link below should provide a good enough selection of threads to figure out what might be done.

exakta to m42 adapter site:www.pentaxforums.com - Google Search


Steve

[yucatanPentax]

Are you meaning the ring with three screw type commonly sold on eBay? They don't work.
[/url]
Steve

Didn't RioRico used to do something similar to those ebay rings?
Glue M42 threads or a PK bayonet onto Exacta lenses? Seems like I remember him writing about that.

Found this: ANNOUNCING: Easy cheap non-destructive Exakta-Pentax adapter

[Lowell Goudge]

If you measure carefully the flange distance, you may be able to remove the exacta mount, add some shims and then glue or screw a flanged M42-PK adaptor

[stevebrot]

Didn't RioRico used to do something similar to those ebay rings?
Glue M42 threads or a PK bayonet onto Exacta lenses? Seems like I remember him writing about that.

Found this: ANNOUNCING: Easy cheap non-destructive Exakta-Pentax adapter

Yes, he did, though I would not try that one on other than a smaller lens.


Steve

[snm]

Thanks all for the comments. I'm currently looking at all the possibilities, and found a few pentacons for parts listed.

Wanted to clarify, since I don't know whether there were any differences in the design when comparing Pentacon vs Meyer-Optik. For example, would a bayonet from this pentacon also fit on a Meyer-Optik (attached a pic)

Visually they look the same, but it's hard to tell without having touched one.

[snm]

I've received another picture with the mount. It visually looks very similar. Could there be something I'm missing, or will this mount from Pentacon work fine on Meyer-Optik?