Topic: Help with a Zeiss Praktica Bayonet to EOS adapter

So I am bidding on a nice Zeiss DDR lens and totally miss that it is a Praktica bayonet mount, I of course win the auction and now have this lens sitting here looking at me. I want to use this on my 350D (Rebel XT) body and of course I cannot find any adapters.

I have read about a few of you guys making one on your own. Does anyone actually sell these adapters?

I have looked on the board and I have not found anything telling me this yet, but I will keep looking.

I did find an adapter to let me use my Mamiya 645 lenses on my 350D, but it is 303.00 so it is something on the horizon.

Thanks!!

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

As far as I known, I'm the only person who made an adapter for practica B lens to EOS body, never seen anyone else make one !

Canon 5DII and a few lens -- Tachihara 8x10. Chamonix 45N-1, Crown Graphic 4x5. Moskva, Zeiss Super Ikonta C
Bronica S2A, Agfa Super Isolette, Iskra, Rolleiflex. Leica M2, Bessa R, Zorki 1,3,3M and a few more...

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Do you plan on making any more? If so will you sell them smile

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

No, its impractical to make them past the prototype stage, and nobody seems interested in manufacruring them. I had quite a few people asking to *get* them but nobody (serious) proposing to *make* them hmm

Canon 5DII and a few lens -- Tachihara 8x10. Chamonix 45N-1, Crown Graphic 4x5. Moskva, Zeiss Super Ikonta C
Bronica S2A, Agfa Super Isolette, Iskra, Rolleiflex. Leica M2, Bessa R, Zorki 1,3,3M and a few more...

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

I will have to speak with my uncle, he is the metal fabricator in the family and see if this is something we can do.

I really do not want to get rid of this lens, so I have to find a way to use this thing, which means I will have to make my own adapter.

Last edited by johnw (2006-02-26 23:52:22)

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

buze wrote:

No, its impractical to make them past the prototype stage, and nobody seems interested in manufacruring them. I had quite a few people asking to *get* them but nobody (serious) proposing to *make* them hmm

Is it possible to change the mount?

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Not practical either. I *did* one like that tho, I dremelled the mount flat, and soldered a M42 adapter on it. It worked but it's really "a bodge".

Canon 5DII and a few lens -- Tachihara 8x10. Chamonix 45N-1, Crown Graphic 4x5. Moskva, Zeiss Super Ikonta C
Bronica S2A, Agfa Super Isolette, Iskra, Rolleiflex. Leica M2, Bessa R, Zorki 1,3,3M and a few more...

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

then my only options are........

Make my own
Sell it
Trade it

or

Keep it and hope someone starts making them, if I don't find a way to do so.

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

I made Prakitcar bayonet mount for EOS cameras, though it only works with
300/350D cameras which have short mirrors.  I did try to use my original mount
for 5D/EOS650, the most of my Prakticars have a problem of "mirror never return",
since 5D/650 have long mirror for long forcal lenses CANON offers.

I was in Tokyo last two weeks, and visited "world famous Matsuya-Camera-Show"
myself, and talked to a guy from ELEFOTO (sells Prakticars and many mount adapters).
He tried to sell me a modified Prakticar 20/2.8 with EOS mount, approx. US$650.
Yes it works with my 5D, it did not have a mirror-never-return problem.  They seem
to have stock of modified Flektogon 20/2.8s. You can contact with them.

Last edited by KOJI (2006-02-28 15:23:21)

B200, BC-1s, BX-20s & 20+ Prakticars & Etc. etc...
http://www.pbase.com/kkawakami

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Oh, forgot to mention about Prakitcar-bayonet to CANON FD adapter.

You can find the above adapter once in a while on eBay, it sure works
and has no problem of infinity forcus. Though no FD digital camera is
available, you may find FD to EOS mount adapter too on eBay. However
I do not know this adapter(FD->EOS) can obtain "infinity forcus".

.../koji

Last edited by KOJI (2006-03-01 19:13:19)

B200, BC-1s, BX-20s & 20+ Prakticars & Etc. etc...
http://www.pbase.com/kkawakami

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Here's a picture showing what has to be modified to make a practica B mount lens fit a K mount camera or adapter

All the measurements seem to match up except for the lug distances.The image below is of a practica lens with a pentax camera mount sitting flush on it so that you can see the difference.
The problem is that the practica lens lugs(A) have 3mm of clearance (1).The Pentax engagement lugs (B) are 3.6mm thick at that point (2).

The two simplest ways to deal with this seem to be to either grind/machine the lens lugs thinner or to grind/machine the K mount adapter lugs thinner.
Unfortunately the two brands of K mount-EOS adapter both have slotted type lugs (to give spring pressure) so any attempt at removing 0.6mm would either cut through to the slot (uh-oh,too much clearance now!;)) or greatly reduce the strength of the lugs.
Thinning the lugs on the lens would work reasonably well but of course they would be weaker then.I doubt this would be enough to matter but still....it's something you'd try to avoid if possible.



http://img131.imageshack.us/img131/5551/1alr6.jpg

Last edited by Ron Chappel (2007-09-12 02:10:35)

Currently: EOS 400d, EFs18-55IS, Homemade super macro lens,Pentax K 50/1:1.2 , Canon FD85/1:1.2 (converted to EOS mount), Tamron 500/8 mirror, Canon FD500/4.5L (converted to EOS mount)

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

thanks for all the help so far everyone, I did have a thought...

Do you think you could modify a Praktica 2x converter to work??

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

KOJI wrote:

Oh, forgot to mention about Prakitcar-bayonet to CANON FD adapter.

You can find the above adapter once in a while on eBay, it sure works
and has no problem of infinity forcus. Though no FD digital camera is
available, you may find FD to EOS mount adapter too on eBay. However
I do not know this adapter(FD->EOS) can obtain "infinity forcus".

.../koji

Being that I do mainly portrait/fetish/glamour type work, infinity is not something I will need very often....so this is a route I will look into as well.

Thanks!

14

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

I have a small collection of PB lenses I use on my 350D. I use two related methods for adapters, both using an alumilite molding kit.

The first method was to make a casting of the EOS section of an M42-EOS adapter and mold an EOS mount directly on the base of a PB lens.

The second method is to make a plastic copy of an M42-EOS adapter and machine this into a homemade adapter. This method actually seems easier although both methods are reasonable easy. The adapters seem reasonably strong enough for my lenses up to 135mm.

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

cool


I just bought a Pentax K to Canon EOS adapter from Ebay Italy, so we will see how well it works soon.

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Buze ,can you explain how your 'Kdapter' fits both mounts?
I *think* i have the same practica mount lens you have but could have made a mistake somewhere.
Does your Kdapter have tapered ramp shaped lugs perhaps? Do K mount lenses twist into the adapter further than practica B mount lenses?

I've got a couple of ideas but want to make sure the basic facts right first

Currently: EOS 400d, EFs18-55IS, Homemade super macro lens,Pentax K 50/1:1.2 , Canon FD85/1:1.2 (converted to EOS mount), Tamron 500/8 mirror, Canon FD500/4.5L (converted to EOS mount)

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Yes, the "infinity plane" was tailored for the Pracrica B, so the Kadapter is only 0.9mm thick or so. I then tailored the "ears" in the adaptor carefuly to ramp up to fit both the B and K lens.. it took a bit of fiddling, and of course I can focus the K lens further than infinity, but it works fine.
I could make a K-only adapter a lot simpler, it would certainly take a lot less work because thinning the original plane to fit infinity on the B mount was quite a lot of work !

Canon 5DII and a few lens -- Tachihara 8x10. Chamonix 45N-1, Crown Graphic 4x5. Moskva, Zeiss Super Ikonta C
Bronica S2A, Agfa Super Isolette, Iskra, Rolleiflex. Leica M2, Bessa R, Zorki 1,3,3M and a few more...

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Ah,very interesting

I can think of ways of making an off-the-shelf (i.e machine made) adapter for both but honestly i doubt it would be worth the trouble.Perhaps even the infinity issue could be addressed with a custom spacer but i can't see many users being worried about that.
Still,i'm glad i now understand it all better

It'll be very interesting to see how John goes with the Kmount adapter

Currently: EOS 400d, EFs18-55IS, Homemade super macro lens,Pentax K 50/1:1.2 , Canon FD85/1:1.2 (converted to EOS mount), Tamron 500/8 mirror, Canon FD500/4.5L (converted to EOS mount)

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Once I have the adapter I will give you guys a report and I think I have a guy with a C&C machine now.

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Got my K mount - EOS adapter today and damn it is a close fit, it snaps down and fits enough that it will stay in place. Now I just have to see if I can modify this one to fit the Praktica B enough to use it on my  350D.

This is the actual adapter....not my photo, I can get a much better one if anyone is interested.

http://i47.photobucket.com/albums/f164/jwilliams44/misc/50_1_b.jpg

The adapter fits well enough as is to take photos, but it's not secure.

http://i47.photobucket.com/albums/f164/jwilliams44/misc/2.jpg

It's at a high ISO, hence the noise

Last edited by johnw (2006-03-16 00:02:08)

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Hi,

I just visited the shop I used to buy all my Praktica gear from way back in the early 1990's, and have "discovered" that he sells a special EOS mount that replaces the Praktica Bayonet mount.

Yes, you have read this correctly, this mount replaces the PB with an EOS mount.  It is supposed to work only with the Pentacon made PB lenses, basically the CZJ P 2.8/28, Pentacon 2.4/50, Pentacon 1.8/50 and CZJ P 2.8/135.

How this "mount" works is very simple.

Step 1: set lens to infinity, and smallest aperture.

Step 2: pop off the black plastic sleeve/collar at the centre of the lens.  This will expose the entire lens mount, including the screws that hold it in place.

Step 3: unscrew the 4 screws holding the lens mount.  The lens mount can now be lifted up and removed.

Step 4: unscrew the 2 screws holding the diaphram release lever.  The diaphram lever can now be removed.

Step 5: align the EOS mount over where the PB mount used to be and screw it on, taking care to align the locking pin's lug to the exact alignment as the PB mount's.

Step 6: pop in the black plastic sleeve/collar back into the centre of the lens.

In all of 2 minutes, you have a Pentacon/CZJ lens with a new EOS mount, and best of all, it can be re-mounted back to Praktica Bayonet if you so desire.

OK, that's how it is supposed to work.  However, on the lens (CZJ P 2.8/135) I tried remounting this morning, the screw holes on the EOS mount did not align with the lens' screw holes.  So, the mount is only attached by 2 out of the 4 screws, and the plastic sleeve/collar.  However, it seems quite stable nontheless.

I will try it out on the other lenses I have tonight, to see if the screws are in alignment with the other lenses.

I have not tried it with a dslr yet, as I don't actually have one, so I really do not know if it is accurate at infinity focus.

I will try to see if i can borrow a dslr from a friend, and try it out, and see if this was worth the US$50 I paid for it...

Let's see how this goes...

Oh, and I also saw a custom remounted CZJ 2.8/20 in the shop.  The mount was custom machined out of brass, and cost him about US$188 to make.  I don't know how well it works though...

Last edited by oloroso (2006-05-01 07:57:55)

Bodies: Canon 5D mk ii, FujiFilm X-M1, X-T1, Praktica BX20, BMS, MTL-5B, MTL-50.
Lenses: Listed here
6 x 6: Rolleiflex 2.8F Planar TLR, Rolleiflex T Type 1 Black TLR, Seagull 4A-109 Red/Gold TLR

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Managed to check the screw alignments of the EOS mount with the other lenses (CZJ P 2.8/28, Pentacon 2.4/50, Pentacon 1.8/50 ), and they do match. 

I've also re-mounted the CZJ P 2.8/135, this time with all the screws in.  The original alignment for the locking pin's lug is no almost exactly on the other side of the lens, instead of its original position.

Will be getting access to someone's 20D early next week, so some test shots should be available by mid next week at latest. 

Till then...

Bodies: Canon 5D mk ii, FujiFilm X-M1, X-T1, Praktica BX20, BMS, MTL-5B, MTL-50.
Lenses: Listed here
6 x 6: Rolleiflex 2.8F Planar TLR, Rolleiflex T Type 1 Black TLR, Seagull 4A-109 Red/Gold TLR

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Sounds great....

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

Hi,

Finally got to test the lens, and boy, it

Last edited by oloroso (2006-05-12 10:17:09)

Bodies: Canon 5D mk ii, FujiFilm X-M1, X-T1, Praktica BX20, BMS, MTL-5B, MTL-50.
Lenses: Listed here
6 x 6: Rolleiflex 2.8F Planar TLR, Rolleiflex T Type 1 Black TLR, Seagull 4A-109 Red/Gold TLR

Re: Help with a Zeiss Praktica Bayonet to EOS adapter

I just bought a Sonnar/Prakticar B-mount 135/3.5 on eBay. ( item 7615018687 )
I know that there's no adapter, and i couldn't even find the flange distance of the B-mount anywhere, so it was a gamble.

But after some mesuring i found out an easy conversion to EOS mount.
I used an EOS mount ring that i screwed of a discarded Sigma Zoom.
I removed the three screw tabs on the inside, and now the EOS mount fits completely over the original Praktica mount.
The difficult part is to turn down the thickness off the mount to about 0.5mm ( about a fingernail thick...)
That is so thin that it is better to make a metel ring first to fit between the lens mount flange and the claws of the lathe to take the pressure.

After i got the mount to the right size, i just glued it on with epoxy.
I also turned the ring with the red alignment dot to the right spot, and i cut off the aperture actuator.

It focusses exactly to infiny. When i use my eyes to focus on the horizon, i find that i can turn the ring about 2mm further till it hits the endstop. Perfect.

Allthought it potrudes into the mirrorbox it doesn't touch the mirror on my digital rebel. But for cameras with larger mirrors a bit of axtra work is probably needed. It's only the inner dust cap that is fixed with two screws, and is easyly removed.

Great lens! Will try to post some pics of the mount later. (The only downside is that it can never be opened again...)


By the way, this is my first post on this forum.
I actually did a google search for "praktica bayonet eos conversion" and found this thread.
Great forum! I will spend more time here.

Marcel.

(From The Netherlands, where we speak dutch, and where we pronounce "Auto Focus" exactly the same as "Out Of Focus"  ;-)  )