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How to convert large format lenses to ltm ?
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PostPosted: Mon Jul 09, 2012 5:27 am    Post subject: How to convert large format lenses to ltm ? Reply with quote

Hi buddies

I've seen some people convert good 6x6 or 6x9 format lenses to m39 mount.Yesterday I saw a voigtlander vitoret III and lens mounted is:Voigtlander 50mm Ultron which is a good lens.Just want to know how can I make it usable

Thank you
Greetings from Turkey


PostPosted: Mon Jul 09, 2012 6:28 am    Post subject: Reply with quote

Is this to mount on a real Leica, Zorki, Fed ?

Leica M39 with rangefinder coupling ? Quite difficult. Would require an expert machinist.

Why do you want it to go in an M39 screw anyway ?

To mount an old 6x9 folder lens on your digital camera -
Simplest is to get a bellows for your camera, and a plastic body cap - if your lens is small enough.
Mount the lens you want on a plastic body cap for the bellows mount. All you need to do is drill the right size hole in the body cap.

There are other ways, if the lens focal length is too short (bellows are good only for 100mm or longer, if you want to go to infinity), you can try a focusing tube. If the lens is too big for a body cap there are a hundred other solutions.

Like this -

http://forum.mflenses.com/bauschandlomb-kodak-5-inch-f-8-rapid-rectilinear-t25908,highlight,%2Bbausch.html

http://forum.mflenses.com/bauschandlomb-planatograph-6-1-2-f-8-a-100-year-ol-t7550,highlight,%2Bbausch.html

http://forum.mflenses.com/bauschandlomb-tessar-164-4-5-enlarger-lens-on-bellows-t11018,highlight,%2Bbausch.html

http://forum.mflenses.com/elgeet-90-4-5-enlarger-lens-flash-t9356,highlight,%2Belgeet.html

http://forum.mflenses.com/elgeet-navitar-10-4-5-on-exakta-bellows-t7500,highlight,%2Belgeet.html


PostPosted: Mon Jul 09, 2012 12:26 pm    Post subject: Reply with quote

Hi Shyl,

The Voigtlander 50mm f/2 Ultron is definitely a nice lens, certainly a good user. However, it is a 35mm format lens, not 6x6 or 6x9. A Vitoret was a 35mm leaf shutter camera, usually outfitted with a front-cell focussing lens, like a Color-Lanthar (3 element lens). It was considered an amateur camera. The leaf shutter is built into the lens.


Maybe you saw this. It is a link to a very strange Vitoret with a L39 lens mount, probably a microscope camera.

http://www.trenholm.org/hmmerk/HMbook12.html#anchor120594

As the author states, the Vitoret camera body is thicker than a screw mount Leica body, so its back focus is about 4.5mm longer than a true LTM camera. This means a LTM lens would not focus to infinity on the body. What this means to you, if you are trying to mount a Vitoret lens on a an LTM body is that you have make your adapter no thicker than 4.5mm.

Do you have an image the lens/camera in question?

Paul


PostPosted: Mon Jul 09, 2012 2:32 pm    Post subject: Reply with quote

As has already been pointed out, 35 mm isn't large format. There are debates about the smallest LF format from time to time on large format forums. To the extent that there's a consensus, 4x5 (that's inches) is the smallest format that qualifies as large.

LF cameras usually -- there are exceptions -- have moveable standards with a bellows between them. Extension is changed for focusing by moving at least one standard.

Lenses in LF cameras are usually mounted in shutter. Some, however, are intended for use on cameras with behind-the-lens shutters, with a shutter hung in front of the lens, or with no shutter at all; these lenses are mounted in barrel. Lenses, in barrel or in shutter, are typically mounted on a lens board that can be attached to the camera's front standard.

Adaptation to smaller formats? Many are the ways. I shoot lenses made for larger formats on 2x3 Graphics and a 2x3 Cambo SC. I've tested most of my lenses by hanging them in front of a Nikon SLR before deciding to use them seriously.

I use barrel lenses (all but one) front-mounted on a #1 Copal shutter. Lens goes into a threaded bushing, often stepped; front female threads to accept the lens' mounting threads, rear threads M40x0.75 to screw into the front of a #1. I have a female M40x0.75-to-male M42x0.75 (t-mount) adapter, use it and a female T-to-male Nikon F adapter to mount lenses for test on a Nikon bellows.

LF lenses in shutter sometimes have rear cells whose diameter is greater than the shutter's mounting threads' diameter. The only secure way to hang such lenses in front of, e.g., a Nikon bellows is to screw an adapter into the lens' rear filter threads. If the lens doesn't have rear filter threads, secure mounting is slightly problematic. One needs a cup-shaped adapter that's a tight fit on the rear cell, with set screws to lock it on the lens.

You can read about the ways I've adapted lenses at http://www.galerie-photo.com/telechargement/dan-fromm-6x9-lenses-v2-2011-03-29.pdf

An approach that I haven't used yet is to mount the small format camera on a plate that attaches to a large format camera's rear standard. If you want to use a variety of LF lenses on small format, film or digital, this can be more cost-effective than having many adapters made. Cambo and low-end Sinar 4x5 cameras are good starting points. So, if you'll never want to use a lens longer than around 600 mm, is the Calumet CC-401.

I know that the OP's target camera is screw mount Leica (or clone). Focusing an LF lens hung in front of a rangefinder camera forces focusing through the lens. Focuslide, Visoflex, or the equivalent, and bellows and ... Not possible with short lenses.


PostPosted: Mon Jul 09, 2012 5:24 pm    Post subject: Reply with quote

"An approach that I haven't used yet is to mount the small format camera on a plate that attaches to a large format camera's rear standard"

I have. Its not hard if you've got a Graflok or Graflex back.

http://forum.mflenses.com/what-to-do-with-a-speed-graphic-in-a-digital-world-t5798,highlight,%2Bgraphic.html

Its got its uses, as you say for quickly checking LF lenses that are already on lensboards. But ut is too clumsy a solution for general use and even with a moderate-sized Speed Graphic its very difficult to use handheld.

I now have an interesting German bellows for Exakta that has interchangable lensboards (of its own type), and seems quite easy to modify otherwise. I am thinking to make a couple of special lensboard adapters for it to take Mini Speed Graphic and 3 1/4"x4 1/4" Speed Graphic lensboards. That would be a manageable and universal solution I think.


PostPosted: Mon Jul 09, 2012 8:02 pm    Post subject: Reply with quote

luisalegria wrote:
I have. Its not hard if you've got a Graflok or Graflex back.


Yes indeed. In fact, plates with male mounts for a variety of "35 mm" SLR male mounts attached are now available off-the-shelf. All, AFAIK, to fit Graflok (= International) backs. Making a plate etc. to fit a Graflex back is not a good idea, cameras with Graflex backs are scarce and most of them are Graflex SLRs with limited focusing travel.

I wouldn't use this approach with a Graphic because Graphics have limited maximum extension. 4x5s have around 12.5", can't be used easily with non-telephoto lenses much longer than 270 mm or with teles much over 385 mm.

luisalegria wrote:
Its got its uses, as you say for quickly checking LF lenses that are already on lensboards. But ut is too clumsy a solution for general use and even with a moderate-sized Speed Graphic its very difficult to use handheld.


Wot? Don't you use a tripod? Shooting a long lens handheld throws away a lot of image quality.

To be fair to you, I don't use my Graphics to get extension for a small format camera. I wouldn't use my Cambo handheld, ever; its too big and too heavy. I have a couple of long process lenses; Cambo + Nikon on tripod looks like a good way to use them on small format or, come the day when I break down and buy one, a digital Nikon SLR. My little tandem Graphic is good to 480 mm, perhaps a hair more with a Nikon behind it. But its no good at all with my 610 and 900.

luisalegria wrote:
I now have an interesting German bellows for Exakta that has interchangable lensboards (of its own type), and seems quite easy to modify otherwise. I am thinking to make a couple of special lensboard adapters for it to take Mini Speed Graphic and 3 1/4"x4 1/4" Speed Graphic lensboards. That would be a manageable and universal solution I think.


Promising idea. How much extension does it offer?

I've done something parallel, used a Soviet bellows in M39 with adapters on both ends to shoot macro with a Nikon and lenses up to around 210 mm. Can't imagine shooting anything much longer handheld, even with flash illumination.


PostPosted: Mon Jul 09, 2012 10:20 pm    Post subject: Reply with quote

I've got one of the fairly uncommon Speed Graphics with a Graflex back; this was a special order option I think, until Speed Graphics in 3 1/4 x 4 1/4 were no longer offered. Its got advantages, such as the ability to use all the Graflex backs, like the bag mags. However its much slower to use with the double-sided film holders than the spring back. The 120 roll holders for this size are very scarce. I just have one in 6x6, I've been looking for years for a 6x9.

This fix works well with my Tele Graflex also, if the object is testing lenses that would work on that thing anyway. It also makes a great lightmeter ! Who needs Polaroid ?

I've rarely had much use for longer LF lenses, my longest is a 15" Optar telephoto which works reasonably well (@20 ft minimum focus) on a 3 1/4 x 4 1/4 Speed. I even had a "top hat" made (by a good friend from mflenses !) to get closer focus with that.

I'm a sloppy, lazy guy, and I hate tripods, and do without whenever I can manage to. My style is to walk around and shoot whatever takes my fancy. Thats why the Pentax DSLR is, to me, the greatest photographic invention since digital photography. That built in Image Stabilization stuff works, even for LF lenses on bellows. Hand-held snapshots with 400mm tele ? - no problem. The 1:1 pixel peeping does not lie.

The bellows is the Multiscope, Seymours imported it for a few years. Its an extra large (widthxdepth) bellows, lonnger than a Mini Speed Graphic (2 1/2x3 1/4), certainly, but I haven't measured the full extension. I don't know if its got more than a 4x5 Speed. Its got its own "lensboards" - plates with the front and rear camera mounts. It should be easy enough to make boards for other mounts, adapters, etc.

BTW, if you need more extension with 35mm bellows, you could just add extension tubes, or extemporized tubing also . I've done that a lot. I have mounted simple 8"-10" lenses on my DSLR with close focus.


PostPosted: Mon Jul 09, 2012 11:17 pm    Post subject: Reply with quote

luisalegria wrote:
BTW, if you need more extension with 35mm bellows, you could just add extension tubes, or extemporized tubing also . I've done that a lot. I have mounted simple 8"-10" lenses on my DSLR with close focus.


Yep, I have around a meter of E. Leitz NY and Leitz Wetzlar tubes, also a couple of female T-mount-to-male LTM adapters and a handful of Novoflex female LTM-to-male Nikon F adapters. All very useful. In fact, I use ELNY tubes with some barrel lenses on my little 2x3 Graphics.

I don't know where prices are now, but when I got mine ELNY tubes were quite inexpensive.

I've always had parallelism problems with extemporized tubing, can't cut the ends perfectly square.

I have 24" of 4" PVC drain pipe, in three pieces (2 x 6", 1 x 12"), for my failed Baby Bertha project. Each of the six inchers has a 2x3 Cambo lens board at one end. Cheap flexible rubber(?) couplers hold them together well enough. Lightweight PVC pipe looks unsuitable for use as extension tubes -- it is translucent and very smooth and shiny inside -- but flocked paper from Edmund Optics cures all that. Failed project notwithstanding, I use 'em on the Cambo without the SLR module.


PostPosted: Mon Jul 09, 2012 11:35 pm    Post subject: Reply with quote

I have mostly been using Exakta tubes since my original bellows were for Exakta.
I have since modified them to fit on Pentax K.

Exakta tubes are very cheap, especially the third party Accura brand.
They screw together btw, M40 thread, except for the end parts.
Ekakta tubes are also useful for mounting lenses - like your LTM tubes I guess -
I wrap paper tape around the lens mounting thread until I get a tight press fit in the M40 screw.