[aurele]

Incredible job ! congratulation !

Here's one I had started a mod on a while back and only recently finished. Working on the mount was a major pain, requiring a good amount of machining.





X-posted to the Gear Porn thread.

Not quite as well known as it's 58mm sibling, but to my eye, sharper with a more modern rendering.

Requisite Kitty picture to show performance:


100% crop:

[ivanvernon]

Anyone know what the Pentacon 6 mount was? I thought it was for a 60x60 medium format camera. If that is wrong what eastern Bloc camera was medium format?

Here is pretty much the full story. Kiev used it and made plenty of medium format cameras.

[carlthellama]

After a few weekends work in the shed I have got my latest lens conversion to the point where it can be tested. The lens (shown a few posts back with a super takumar 50mm f1.4 for scale) is a Wray 36"f/6.3 reconnaissence lens which I believe dates from the 1940s. Apparently these were originally used for arial reconnaissence taking images on large format negatives (10"X8" I believe).

The attached photos bellow show the construction and the finished lens.

The first photo shows the component parts of the lens. These consist of:
The lens
A margarine tub lid (found to be exactly the right size to be used as a lens cap),
A clear plastic flange for bolting to the lens (built up from two hand sawn disks of 12mm plastic),
A plant pot with the bottom cut out (for building up the glassfiber section),
A plastic amunition transport case (salvaged on its way to a skip!)

The second photo shows the first stages of the build.
The glassfiber section has been built up around the plant pot with the plastic flange as an integral part of it. This was built up around the green plastic case to get a good fit and a layer of cling film was used as a release agent to prevent it sticking. An old bellows unit has been modified so it can be used as a focus mechanism and the mount for this has been bolted into the end of the green plastic case.

The third photo shows the above parts push fitted to show the assembly. After this photo was taken the wide end of the green plastic casing was cut of and the whole lens was trial assembled (push fitted only). Once it was dark I took it outside to find the infinity focus position using the moon as a target. Once this was found screw holes to hold everything together were drilled and more glassfiber and filler were added to the front section and sanded back to get a good finish. The glassfiber section was then painted and the inside of the green tube was lined with black paper to reduce scattered light.

The final phot shows the completed lens assembly mounted on a very heavy duty tripod (this thing is really heavy) with the Samsung GX20 mounted on the back. The tripod mount is right under the ballence point of the lens with the camera on the back. As the GX20 waights about half a kilogram you can imagine how much the lens must weigh for it to ballance as it is!

The lens is by no means finished and some work still needs to be done to improve the image quality and rigidity etc. I will post some photos taken with this once I have had a chance to sort them out.

By far the coolest thing I have ever seen.

[DimiTator]

CZ Planar 50/1.8 in Rollei QMB mount (wide open) ... it will (force) fit ever so nicely on a PK, but nothing past 1.5m due to registration difference ... OK by me, I like to shoot close. Got it for a song at a swap along with the Voigtlander in Rollei QMB, but it does not fit as well ... note the spider's web.



@ about f2.8 ...

Monsieur Poitier, je vais vous envouyez une question par PM concernant le Cardinar.

[DimiTator]

CZ Planar 50/1.8 in Rollei QMB mount (wide open) ... it will (force) fit ever so nicely on a PK, but nothing past 1.5m due to registration difference ... OK by me, I like to shoot close. Got it for a song at a swap along with the Voigtlander in Rollei QMB, but it does not fit as well ... note the spider's web.



@ about f2.8 ...

Bonsoir monsieur Poitiers,

J'ai vu que vous avez d'experience avec l'objetif "Cardinar" (Werra-mount), que vous avez convertez par Pentax.
Moi j'ai achetez une Cardinar en tres belle etat! Hélas, je n'ai aucune idee pour le converter par une autre camera. Moi j'au uneNikon. Pouvez vous m' aider par la conversion, je na sais d'ou commencer? Je suppose que ca sera similaire avec votre Cardinar, sauf que je dois adapter a Nikon.
Merci d'avance, et bien à vous.

By far the coolest thing I have ever seen.

Good evening Mr. Poitiers,

I saw that you have experience with the lens "Cardinar" (Werra-mount), which you have converted to Pentax.
I bought a Cardinar in very good condition! Unfortunatley, I have no idea how to convert it to another camera. I'm at Nikon. Can you help me by conversion, I do not know where to start? I guess it will be similar with your Cardinar, except that I have to adapt to Nikon.
Thank you in advance, and good to you.

[Jean Poitiers]

Bonsoir monsieur Poitiers,

J'ai vu que vous avez d'experience avec l'objetif "Cardinar" (Werra-mount), que vous avez convertez par Pentax.
Moi j'ai achetez une Cardinar en tres belle etat! Hélas, je n'ai aucune idee pour le converter par une autre camera. Moi j'au uneNikon. Pouvez vous m' aider par la conversion, je na sais d'ou commencer? Je suppose que ca sera similaire avec votre Cardinar, sauf que je dois adapter a Nikon.
Merci d'avance, et bien à vous.


Good evening Mr. Poitiers,

I saw that you have experience with the lens "Cardinar" (Werra-mount), which you have converted to Pentax.
I bought a Cardinar in very good condition! Unfortunatley, I have no idea how to convert it to another camera. I'm at Nikon. Can you help me by conversion, I do not know where to start? I guess it will be similar with your Cardinar, except that I have to adapt to Nikon.
Thank you in advance, and good to you.

Bonjour,

I am an American living in France and I prefer to answer in English ... and here so that everyone can benefit from the information.

What I have used is a cheap set of Chinese extension tubes for a K-mount ... the Cardinar lens will fit snugly inside the opening of the K-mount front tube and behind that I used "hard" felt material to secure better the lens. I cannot set the aperture from the outside ... one has to use a fingernail and move it manually inside this home-made mount system.

Please find below some images which may help you ... I unfortunately do not known about Nikon systems, thus I cannot advise you about any specifics there ... try the extension tube set-up with your proper Nikon mount and depending on the length of the tubes, you can have a near macro result ... longer tube length = closer to a "macro" or close focus image.

I just tried this lens set-up on the K-1 and it will work on a full frame ... but, the far focus is about 1 meter max. as now assembled. Plus my Werra 100mm lens is a bit "sick" and I need to attend to it ... the lens barrel will pull out of the body, so I need to put it back correctly and re-align, etc. ... another "rainy day" project.

Hope this helps and feel free to post here if you have any questions ... Salut, J

[Jean Poitiers]

Monsieur Poitier, je vais vous envouyez une question par PM concernant le Cardinar.

Hi, I just sent you a PM to tell you that the information is on this thread ... also, I forgot to add a sample image of the lens used on the full frame K-1.

Here it is ... rather hastily made in the back yard. Shot wide open and at about two and half feet distance ... Cheers, J

Attached Images

View Picture EXIF

File Date

 

[DimiTator]

Hi, I just sent you a PM to tell you that the information is on this thread ... also, I forgot to add a sample image of the lens used on the full frame K-1.

Here it is ... rather hastily made in the back yard. Shot wide open and at about two and half feet distance ... Cheers, J

Thanks a lot Jean, this really helps me!

[aurele]

Hello everyone,

I've got a Minolta MC Tele Rokkor PF 100mm f2.5 that i'd like to convert.

Does anyone already done it ?

I haven't seen a post related to it, so i'm asking. But so far i don't think it has been done.
I'll have to find a way to shave 1mm somewhere !

[swanlefitte]

Aurele, This tread might be a good starting point. It also deserves a link here anyway.
Konica, Minolta, etc. mount to Pentax K - How to save the old lenses - PentaxForums.com

[aurele]

Aurele, This tread might be a good starting point. It also deserves a link here anyway.
Konica, Minolta, etc. mount to Pentax K - How to save the old lenses - PentaxForums.com

thanks !

The main difficulty is that the mount is not visibly screwed to the rest of the lens.

Otherwise i would have done as usual : M42 to K adapter to replace the minolta mount.


EDIT : took a peak at the body and the mount is way too annoying to get : You have to unmount the back of the mount groupe. Dismantle all the aperture lever things (and those tricky little springs), to get to the mount. Mount that is like sandwich-ed between two piece of the mount bloc. Meaning you have to get an adapter, shimmed it to a small ring aroung the mount it self, create screw thread in it, then remount the whole thing.

I'm not equipped nor skilled to do this. Sad because this is a real keeper !

[Mothballs]

This is beyond impossible.

a 24mm-ish F???? Franken-lens.

Front lens block from a cheap broken Yashica kit zoom. Back lens block from some random projector lens. Lens body from a Pentax-M 50mm f2.

Scarred the back element, but luckily i know what the diameter and focal length are, so hopefully I will find a replacement.

Soft as heck, but stops down to be very reasonable.

[GUB]

Retina Curtar Xenon C f1:4 / 35mm. This is in fact only half a lens -- the other half is permanently attached to a 1950s model Retina camera. You could choose to attach either this 35mm front or a 50mm front. I am not sure whether the 35mm f4 refers to the full combination or is a technical description of this half. But this half attached to the K1 feels about right for 35mm but dof and exposure value feel nearer to f8or even f11. (A shot in just under full sunshine was about a stop underexposed at 1/250 iso100) The subject photos are uncropped FF.
I used a 25mm m42 tube to adapt the lens and this was a mistake. I hadn't left enough extension for a bellows or helicoid to fit as a focusing aid. So I am stuck with 1.5 metres and under if I want to focus adjust.

[swanlefitte]

Very cool images. Esp the first and last.

Edit: all of them.

[cprobertson1]

I was just pointed here by a fellow pentaxian! Given that it involves sticking bits of glass and plastic where they don't belong, I thought folks might find this DIY lens I've been working on to be of interest!

The attached photos show the baseplate which will allow me to attach other bits and bobs to it as I design and experiment - it's working pretty well so far (I'll include some example shots soon!) - and the CAD image shows my planned aperture system (plastic, card, or metal plates).

The baseplate is fitted onto the camera via an M42>PK adapter - it's made to be slightly smaller than the M42 thread diameter so that it will self-tap when screwed onto it - and after that, there are six M3-sized mounting holes for whatever I want to add on. The current plan is to add an aperture-plate holder with room for me to screw a filter adapter onto the front so that I can then comfortably mount other filters onto the adapter.

It is an approximately 50mm lens, with a maximum aperture of F/2. My smallest drill is 0.1mm, which means I can, in principle at least, stop it down to F/500 - but with an aperture 100-microns wide (plus maybe 50% for drill wobble), we're going to be dealing with diffraction on a whole other level!
--EDIT--
Or rather, it would be capable of that theoretical F/500 if the vignetting didn't destroy the image leaving only a tiny clear space at the centre where diffraction wins! The thickness of the plate would need to be less than the diameter of the hole to reduce this vignetting - and I can't reliably print a single layer 0.1mm plate!

Will hopefully have more sample pics tonight - maybe even with the new aperture plates!