MD Rokkor 50/1.4 + 45/2 converted to AF mount PICS

After successfully converting a rokkor 45mm f2 lens by following Pete Ganzel's idea, I decided to convert a much more desirable lens. The 50mm f1.4 rokkor has the same optical formula as the Sony/Minolta 50/1.4 and this is probably the closest one can get to the AF version of that lens with the least amount of money spent.

Basically you grind off the old MD mount lug and epoxy (JB-Weld) the M-AF mount lug on. You'll need to shave an extra 1mm down until flush with the edge of the rim to maintain infinity focus. I did this on the 45mm rokkor, but on the 50mm, i only shaved down .5mm and adjusted the infinity focus by removing the front filter mount and using the adjustment screws to extend the glass elements out by .5mm. Now both lenses focus to infinity perfectly and are very fun to use!




Pricelist:
-45mm/2 rokkor $10 (free mount from junk lens) = $10
-50mm/1.4 rokkor $25 + $7 m42 to MAF adapter (only lug used) + $32

Of course if i count the hours spent working on each lens (about 2-3hrs) the cost goes up, but it's fun to work on these lenses, you'll gain a great deal of knowledge on how optics work and will feel a huge sense of accomplishment. Consequently these are my new favorite lenses to have on the body, I think a little bit of old school on a new DSLR looks sexy : )










Here's an updated diagram to show exactly how much of the m42-MAF adapter should be harvested.



Edited by salvageland - 31 March 2010 at 05:15

clarencewstone wrote: hey I'm looking to do the exact thing you mention. However, what is exactly the m42 mount adapter you are talking about? I havent came accross that before.

It's one of these....you just need it to harvest the Sony mount, just the lug part....the cheapest way to get the mount is one of these m42 to MAF adapters, or if you have a cheapy or broken lens that's useless to harvest the mount lug from...

clarencewstone wrote: hey savage! thanx for the help I just went to pete ganzel's site and i think im getting a decent understanding on how this is going to work. If you've done this procedure before how would u rate the difficulty? Just dont want to get in over my head lol

Its quite simple if you're a hands-on/DIY kind of person. The hardest part is harvesting the AF mount, you need to make sure to not shave too much material off from the base so that it will screw into the camera, and not to leave too much material so that it's not loose when screwed into the camera....The easiest way to do this is to fit/test the removed mount lug on a Minolta film body that you don't need to make sure the lug is flush against the camera mount...

On the original MD mount, you'll need to dremel off the old lug, and shave down the whole base of the mount with either a belt sander (quicker) or by putting sand paper flat on a counter and moving the mount in a straight back and forth motion on top of it (slower, this is the method i used).

The easiest part is sticking both parts together, just make sure to align the lug so that the aperture markings are on top, but it's not very critical to do this, just more aesthetically pleasing. You can use very little epoxy at first, just a few drops to set it then come back and fill the inside rim of the mount lug with another layer of epoxy....It usually hardens in 3-4 hours, and is ready to use!

Edited by salvageland - 31 December 2009 at 03:07

dogears wrote: Great job and thanks for sharing... When I finally get my hands on a MinMD50/1.4 I will have to try this, I know it can be found cheaper than the 45/2 and I can get two - 1 to try and 1 to use w/ the EOS-MD flange :P

thats so weird i just picked up a md50/1.7 and a 45/2
cant wait to get to work =P

salvageland wrote: clarencewstone wrote: hey savage! thanx for the help I just went to pete ganzel's site and i think im getting a decent understanding on how this is going to work. If you've done this procedure before how would u rate the difficulty? Just dont want to get in over my head lol Its quite simple if you're a hands-on/DIY kind of person. The hardest part is harvesting the AF mount, you need to make sure to not shave too much material off from the base so that it will screw into the camera, and not to leave too much material so that it's not loose when screwed into the camera....The easiest way to do this is to fit/test the removed mount lug on a Minolta film body that you don't need to make sure the lug is flush against the camera mount... On the original MD mount, you'll need to dremel off the old lug, and shave down the whole base of the mount with either a belt sander (quicker) or by putting sand paper flat on a counter and moving the mount in a straight back and forth motion on top of it (slower, this is the method i used). The easiest part is sticking both parts together, just make sure to align the lug so that the aperture markings are on top, but it's not very critical to do this, just more aesthetically pleasing. You can use very little epoxy at first, just a few drops to set it then come back and fill the inside rim of the mount lug with another layer of epoxy....It usually hardens in 3-4 hours, and is ready to use!

I've got a real good picture as to how I would go about it.
but as a photographer im more visual. I saw there was someone on a previous thread who had a play by play with pictures.
Can you point me towards any direction that would have that?
I also read that to achieve infinity focus im supposed to just keep guessing how to position that bottom bracket that goees around in quarter turns?

Edited by clarencewstone - 31 December 2009 at 09:21

=D
i love the picture
thank you!! it makes me feel so much better aobut playing operation on my lens.
I will let you guys know how it goes.
If i use the m42 rings it will function identical to the amount right?

travfar wrote: What's a better lens? The Rokkor 50 or the Super Takumar 50. I have both. The ST is easy to use with an adapter. Is it worth the effort to get the Rokkor working?

I've never used the TC 50, and i must say that I've been keeping an eye out for that lens for quite some time, but they seem to be going for quite a bit of money $50-$80. The other issue with those lenses are the yellow irradiation of the old optics that throw off the white balance. I decided to go with the Minolta 50 because it's readily available for great deals on ebay. Most of all I went with the Minolta because it's like staying within the company haha i know that sounds cheesy but the lens itself looks good on Sony cameras, the orange focal length mark matches with the orange alpha badge! Another thing is that these MD lenses are nice and compact and tend to have better coatings than older screw mount and Minolta MC lenses.

Now with all that said, I agree with you that the TC lenses are just drop in with the correct adapter and if one is not so inclined to do some hands on work, they should consider getting screw-mount lenses instead.