First time newbie - Antique Bauch & Lomb lens for dslr

[DirkStigNasty&Barry]

Hi all,

I'm new to this forum and new to this concept, so forgive my extreme inexperience. My interest lies the most in using really old antique glass, as there's something that captivates me about it.



I recently picked up an old Bausch & Lomb Zeiss - Tessar 1c from ebay (my first attempt at trying to retrofit an antique lens to my Canon Digital Rebel XT dSLR)

I'm not sure where to start.


(I put the lens up to the opening of the dSLR and it was basically a blur- though putting the lens up to my eye, if I can get something in focus, it looks incredible-better than the Canon dSLR lens I currently use IMO). It doesn't appear to have a focus ring on the lens, though the front piece of the lens does twist around (does nothing). The aperture works perfectly.

Does anyone have any advice where I could start in trying to retro fit this to work on my Canon Digital Rebel XT dSLR? Google searches return very scant results on the subject (mostly just pics and videos of other people who've done it, and this forum)

Pics of the lens attached. Thanks!

[DirkStigNasty&Barry]

p.s. I saw on another post a focusing helicoid with a screw mount. Would I just have to get something like that and an adapter to fit that on my dSLR to get it to work? Forgive me if I answered my own question.

[Lightshow]

Lenses are designed for a specific back focus distance(registration) to make infinity sharp, closer than that distance, everything will be OOF(out of focus), I believe this is a LF(large format) lens that has a larger registration than your DSLR, a bellows should help with focusing, you just have to find a way to adapt it, an M42 bellows with an M42 to EOS adapter should serve you well.
There are also focusing helicoids on ebay with screw threads, so, yes that could work for this lens, but may not for another lens.
The first thing you need to do is find out how much distance between the rear of the lens and the camera mount there is when distant objects are sharp, you then need to fit everything(bellows/helicoid) within that distance.

[luisalegria]

Nice one.
That's a quite early piece for B&L.
Made under license from Zeiss
Its a series 1c for 5x8 inch coverage so under the Zeiss/B&L system the focal length was 8 1/2 inches.
Or about 215mm
You can test that by putting it in sunlight and trying to focus a pinpoint. The distance from the pinpoint to about the center of your lens would be the FL.
Its not a small lens and the FL is rather long so you will need bellows. Focusing tubes normally would be rather short and will not have a long enough helicoid. Any bellows that fit your camera or that can be adapted would do to give a reasonable focus range for a 215mm lens, though maybe if you want to go to closer focus range you may need to add an extension tube.
Putting this lens on bellows needs a bit of thought. Its a bit wide for my favorite drilled bodycap method. What's the thread diameter?

[luisalegria]

Is that f/4.5 or f/6.3?
If its the 6.3 it may actually fit in a bodycap.
Get a bellows for your Canon. Fitting a bellows is just like mounting a lens. You can use a proper Canon bellows or one for any mount for which you have a canon adapter.
Get a plastic bodycap ($1-2) to fit the other end of the bellows, whatever mount it is. Canon is good as the mount diameter is quite large.
Drill a hole in the bodycap just slightly smaller than the thread on the lens. You should be able to screw the lens firmly into the plastic. Then just mount the lens on the bellows and you are set.
I suggest using a hood with this, BTW, as its very likely to flare.

[DirkStigNasty&Barry]

Thanks for the detailed responses! More than helpful.

It's an f4.5. I'll have to run down to the hardware store to measure the thread. There are actually two sets of threads in the back. One set on the inside by the glass and then a set on the outside where the brass begins. There are also threads in the front on the inside. Does anyone know what kind of mount this is?





I was looking around at some bellows online and found some fairly decent looking ones for around $50. All that I've seen go up to around 125mm max. If the focal length of the lens is 215mm, does that mean I need to also get an extender to make up the difference? Am I looking at the wrong bellows?

[kds315*]

http://photographyoftheinvisibleworld.blogspot.com/2011/01/how-to-determine-length-of-focusing.html

[guardian]

[luisalegria]

You will want to use the external male thread, not the internal female thread, That is normally used for the retaining rings holding in the lens elements. Its also harder to get a male fitting on the mount end of anything.

The external thread on this lens was screwed into a brass flange that was in turn attached to a lensboard by screws. This lens was meant for a fairly large 5x7 view camera or possibly a very large early reflex like a Graflex. The thread itself was not metric but American, what the specs were I have no idea, but you certainly would not be able to find a modern lens mount adapter for it. You will need to kludge up your own.

It is possible to find the antique flange that this antique lens was meant for, but it would be quite an undertaking. And it wouldnt help you much as that flange would be even harder to adapt as a mount than the thread on the lens.

For larger lenses one workaround I have used a lot is a T-mount. Look for t-mounts (sometimes called t2-mounts) on ebay. On one side they have a camera lens mount - any mount is available. On the other they have am M42x.75 thread in an inner ring held on by setscrews. If your thread is a bit smaller than M42 then you can wrap several layers of tape on the thread and screw it in to the M42 thread. If a bit bigger than M42 you can remove the inner ring by loosening the setscrews and use the setscrews to hold the taped lens in the T mount. I have even made my own custom general purpose T-mount adapter by drilling out the setscrew holes and tapping them for thicker and longer screws.

Many other kludges are possible.

If your thread, for instance, is close to one of the usual filter threads (and there are many more of them than the usual 49, 52, 55, 62 .. ) you could use a combination of filter adapter rings and a thing called a reverse adapter-camera mount on one end, MALE filter thread on the other. I have done this a few times too.

[luisalegria]

Almost any SLR bellows will do. If you plan on sticking this thing on a Canon DSLR there are cheap mount adapters for anything. Nikon for instance.

http://www.ebay.com/itm/Camera-bellows-/111400337053?pt=US_Lens_Adapters_Mounts_Tubes&hash=item19effa3e9d

Get a Nikon-Canon adapter, of the cheapest sort, plus this thing, and all you have to do is figure out how to get your lens on the other end of the bellows.

200mm is a bit long for most SLR bellows, but thats what our other cheap friends, extension tubes, are for.

Extension tubes -

http://www.ebay.com/itm/Macro-Extension-Tube-Ring-For-CANON-EOS-EF-DSLR-SLR-Camera-lens-/170883727602?pt=US_Lens_Adapters_Mounts_Tubes&hash=item27c976c0f2

With a bellows setup extension tubes can go on either end of the bellows, but I like using them on the lens end.

Sample setup, one of mine, with bellows and extension tubes -

http://forum.mflenses.com/wollensak-enlarging-raptar-162-4-5-on-bellows-t7250,highlight,%2Bwollensak.html

[philslizzy]

Bellows and a short extension tube too. You could mount it, as another respondent has said, in a body cap. I prefer to use a 'reverse adapter, this has a camera bayonet on one ens and a filther thread on the other. get a wide one 55mm for example, ignore the filter thread and push the lens into the hole. Use lots of hot glue to hold it in place and it will not budge until you pull it sharply out then the glue will come cleanly away. with no damage to the lens.

As its meant tor large format you'll be using the 'sweet spot' ie the centre of the lens and should get excellent results. Good luck and share your experience here - good or bad.