which ltm2m adapter do you use for the vogtlander 15?

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for my voigtlander 21 i use the 35/135 adapter on my m6/.58, because it gives the most uncluttered view. i am planning to get the 15mm lens. which of the three adapter versions is most suitable? maybe it could help to judge the size of the metering spot?

which is the best place (=cheapest) in the UK to get them? i found them for gbp 35. anywhere better?

-- stefan randlkofer (geesbert@yahoo.com), May 19, 2002

Answers

I use an old Leica one because I've measured that the Leica ones are a slightly different thickness from the modern copies, and I figure that they knew what they were doing more than the new guys, and that it was going to be a critical issue with that particular lens, given the relatively tiny margin of error it would allow.

-- Michael Darnton (mdarnton@hotmail.com), May 19, 2002.

michael, as i see it, the thickness of the adapter is not very important, because the mechanical linkage for the focus distance is done by the brass ring on the lens and the roller in the camera. otherwise a screwmount lens could never be exact. so even a lens which is not screwed in all the way in should give correct focus if focused with the rangefinder, though the distance scale would be off. correct me if i am wrong!

-- stefan randlkofer (geesbert@yahoo.com), May 19, 2002.

of course, this lens is not rangefinder linked, but the depth of field should be enough to cater for that difference. but you might have a point here.

-- stefan randlkofer (geesbert@yahoo.com), May 19, 2002.

I use the 50/75 ring, because a 50 or 75 is the only other focal length I'm likely to get that would need the adapter.

Since there is no reason to EVER look through the built-in finder when using the 15 (no focusing/unmetered bodies) it doesn't matter how cluttered/uncluttered the built-in finder is.

-- Andy Piper (apidens@denver.infi.net), May 19, 2002.


Stefan, use whatever adaptor you find for the least money, but get a genuine Leica adaptor. The aftermarket ones I tried all left the lens slightly askew (i.e. not lined up at 12 o'clock)which looks like heck. I don't think those fins on the front of the 15 is really a lens hood, but there to protect the front element, however for some reason they don't completely encircle the lens and so might cause vignetting if not lined up square to the film format.

As to judging the metering area with an M6, you can pretty much figure it's *all* of the in-camera finder. With an M7 on AE you could just use the accessory finder and imagine the usual spot the same proportion as the white dot on the shutter curtain.

-- Jay (infinitydt@aol.com), May 19, 2002.



Beware of the phase angle of the adapter's LSM thread...One of my Ebay bought noname specials is off a bit.....what happens is the lens scale is slightly off.. It sounds like not a big deal to someone who has not ever owned the 15mm lens..The lens shade ears of my 15mm are not vertical when the noname adapter is used and my M3.. What one gets with this combo is shading in 2 corners of the film; due to the 15mm lenses ears blocking the light...Kelly

-- Kelly Flanigan (zorki3c@netscape.net), May 19, 2002.

This has been covered many times before. It does not matter which framelines your adapter brings up. It is very common for LTM lenses to line up with the aperture index offset toward the finders. Finally, it is very easy to unscrew the mount off the 15 Heliar and rotate it to a different set of mounting holes so that the hood is square.

-- John Collier (jbcollier@shaw.ca), May 19, 2002.

John; Are you kidding! or NUTS? re: "Finally, it is very easy to unscrew the mount off the 15 Heliar and rotate it to a different set of mounting holes so that the hood is square."

The no-name cheapie/ebay LTM to M mount adapter of mine is 30 degrees off..The adapter's starting thread position is muffed up....They sell this crap on ebay as bargains....and would not give a refund.. The 15mm heliar of mine has 4 screws 90 degrees apart at the rear..Any dissasembly of the perfectly good 15mm 360 dollars lens is still going to only rotate the lens to one of the 90 degrees apart settings.. Since the 35 dollar adapter is off 30 degrees; none of the four 90 degree rotations will correct the problem...

The lens fits perfectly on half of my russian LSM cameras..Many of these camera bodys cost less that the adapter! Maybe the adapter companys should study russian precision! Why ruin /drill a perfectly good 360 dollar lens so it can fit with one BASTARD LSM to M adapter???????????????? The other 2 adapters of mine are ok; one is made by a company called Leitz in a city called Wetzlar; and the other company makes the Bessa.... The screwed up adapter has no name; because they dont want their name associated or used as another name for horse manure Kelly

-- Kelly Flanigan (zorki3c@netscape.net), May 20, 2002.

Haven't taken your Heliar apart, I see, to actually know what's there. Actually there's a series of screwholes behind each single screw, to allow for centering, but not enough holes to do the job if the lens is too far off. If top dead center is beyond either of the f/8 DOF marks you'll get vignetting; otherwise, no.

"michael, as i see it, the thickness of the adapter is not very important, because the mechanical linkage for the focus distance is done by the brass ring on the lens and the roller in the camera. -- stefan randlkofer"

Since the linkage moves at a different rate for all lenses other than the 50mm, this isn't going to bail you out if your adapter is bad for lenses other than the 50.

-- Michael Darnton (mdarnton@hotmail.com), May 20, 2002.


And you originally asked about the 15, not the 21, remember? No RF coupling on the 15.

-- Michael Darnton (mdarnton@hotmail.com), May 20, 2002.


Michael; Re "Since the linkage moves at a different rate for all lenses other than the 50mm, this isn't going to bail you out if your adapter is bad for lenses other than the 50."

The three different types of adapters for LSM to M only differ in one feature. That is the little special piece on the adapter that engages the framelines on the M series camera. The Leica M lenses also have this feature.

The three different types of adapters (that I know of) all have the same thickness. A 15mm Heliar can be used on any of the three types with no focusing problems. A 135mm lens can be used with a 50mm LSM to M adapter too; you just will not have a 135mm frameline in the finder. My M3 has no preview lever; I prefer to use the correct adapter.

The cam roller & lens cam moves at the same rate and distance for all lenses. On a 50mm lens the lens cam is usually directly connected to the lens block. A lens longer or shorter that 50mm has another helical thread in the lens. This is because the lens block moves either faster or slower than the lens cam surface. The distance that the lens cam & camera rangefinder cam moves is tied to the distance that the leica camera is focused. Almost all LSM and all Leica M's cams move the same distance when focusing from infinity to 1 meters. The rangefinder's input is the roller cam. When the images in the rangefinder align at an object 3 meters away; all the different focal length lens have their/his/her own cam surface at the same postion.

-- Kelly Flanigan (zorki3c@netscape.net), May 20, 2002.

Kelly, get out a caliper and measure your adapters. I have seven or so, and they are not all the same. The Leica ones measure consistently thinner than the off-brands, by at least .04mm or so. The Leica ones, interestingly enough, are .06mm thinner than the theoretical 1.00mm thickness, where the off-brands are pretty close to theoretical. I suspect this has to do with Leica's admission that the interface isn't going to be perfect, and will always vary on the plus rather than minus direction.

As with everything else where there's a disputation of standards (the Konica vs Leica fit, for instance) I'll go with the people who've been in the business for decades and know what results they get in real life, vs the new kid on the block who's working on theory rather than experience.

In the current example, if the 50mm lens is mounted out 1mm farther, the RF will simply move it back 1mm, into the correct position. A 25mm lens, however, will be adjusted by the RF to move the *cam* back 1mm, which will result in 2X the actual displacement of the lens itself necessary to correct the error.

-- Michael Darnton (mdarnton@hotmail.com), May 20, 2002.


Sorry--that's half the movement necessary that the lens moves back for every movement of the cam itself, not twice.

-- Michael Darnton (mdarnton@hotmail.com), May 20, 2002.

i have both the 12 and the 15, with one 28/90 voigt adaptor.

the 15 lines up square, the 12 goes past tdc. if i rotate it square it's not very tight. luckily, the hood on the 12 is adjustible, so i crank the lens on and adj. the hood.

-- steve (leitz_not_leica@hotmail.com), May 20, 2002.


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