What a beauty (warning: might cause GAS)

[outfitter]

Sonnars in LTM are mostly humps made up from parts and semi finished goods looted from the factory during the period of post-war "confusion". The Soviets themselves took many parts and made them up in LTM (some faked as Zeiss). Most of the heads of the barrels seem to be of Zeiss manufacture but the bodies and lower halves have been manufactured by a different method from the original Zeiss. Even where the the finish on the barrels seem to be like the official Zeiss products the giveaway is that the focal length is often Contax 52.4mm not LTM 51.6mm.

 

[40oz]

whatever :/

 

[outfitter]

whatever :/

Whatever what? Is your vocabulary so limited you can't finish the sentence?

 

[Paul T.]

Could the legendary inaccuracy of the Jupiter 3 on a Leica be down to the focus shift?

Has anyone tested J-3s, or Sonnar 50/1.5 on a Contax or Kiev, under rigorous conditions? Presumably there must be some focus shift there?

I noticed my Opton Sonnar was misfocusing on my R-D1 and had the adapter adjusted - now of course I wonder if it was equally misregistered on my Kiev 2 and I'd never noticed - purely because it's far easier to test for correct focus on a digital camera than to waste film on it....

 

[outfitter]

I must confess that I know just enough about the subject to get really confused. I know that in manufacture there is a range of focal lengths that are within the tolerances specified for each lens and that manufacturers like Leica have a whole range of cams depending on the actual focal length a particular lens. I also know that the Contax standard for the 50mm lens is 52.4mm while the Leica is 51.6mm (which is why my J-3 in LTM focus 4 inches behind on my Canon 7 at 8ft).

Now I start to get into trouble with the practical application of this knowledge. For example you can collimate a lens to focus at infinity but it will be off at closer distances (and visa versa). Now we get into a moving target short of thing. My LTM J-3 works just fine (more than fine) at infinity and closer distances because depth of field (I prefer f5.6 through f11) and no RF lens works all that well at closer distances wide open unless collimated for that distance (in which case far distances will be off).

Am I to conclude that if the lens is set at infinity the Contax vs Leica standard means the close focusing error is greater if you mix lenses and bodies, but if you are collimating for closer distances the different standards are not all that significant as you are changing the focal length anyhow? What closer distance would you collimate to - you like 8ft but what is the effect of that adjustment at closer and longer distances? Finally what does focus shift mean in this context?

To reduce this to practical terms, I use RF cameras mostly to shoot people (either frame filling or intermediate distances) and rarely for landscapes. I assume all factory collimation is done at infinity. What would be the most practical distances to collimate 35mm, 50mm, 85mm/105mm and 135mm lenses and what could I expect at various distances? :bang:

Michael

 

[ferider]

To reduce this to practical terms, I use RF cameras mostly to shoot people (either frame filling or intermediate distances) and rarely for landscapes. I assume all factory collimation is done at infinity. What would be the most practical distances to collimate 35mm, 50mm, 85mm/105mm and 135mm lenses and what could I expect at various distances? :bang:

Michael

I think it really depends on your shooting style, Michael.

For what I do, the only reason to have fast normal-short tele RF lenses is
wide open, close-up portraits or similar. All my lenses are selected to perform
well like that, and, the last time I counted, I have 6 Sonnar variants (LTM),
all in use. This includes both ZK 50/1.5 and 85/2, BTW.
Also, both ZK lenses work well wide open, close up and at infinity.
But the 85/2 has a minimum distance of 1.8m ...

While I do shoot landscapes, I typically stop the lens down at least 1 stop,
when focusing at infinity. Not only because of possible collimation issues
(all my lenses now are fine close up and at infinity), but because the
lenses get more corner/corner sharpness. Also, 40mm and wider is much
more practical for landscapes, anyways.

For my eye, most decently designed 50mm lenses behave very similarly
at f4 and up. So if f4 and up would be my main target, I would probably
walk around with a 50/{2.8-3.5} Elmar or LTM Heliar, for size, resolution
and contrast.

WRT the focus shift, I think this is highly overrated. For 50mm, the error that
you get by moving the point of focus out of the center (say into the 1/3rd corners),
is typically larger than a Sonnar's shift (at least for my lenses).

Look at my avatar. The major reason to use the Nokton instead of a smaller 40/2 lens
is it's close focus distance of .7m, which enables the above mentioned portraits.
In all non-portrait situations this lens gets stopped down one stop at least.

YMMV,

Roland.

PS: I assume that most lenses are collimated to infinity, when they leave factory
or CLA, because such collimation is simpler, technically.

 

[outfitter]

I think it really depends on your shooting style, Michael.

For what I do, the only reason to have fast normal-short tele RF lenses is
wide open, close-up portraits or similar. All my lenses are selected to perform
well like that, and, the last time I counted, I have 6 Sonnar variants (LTM),
all in use. This includes both ZK 50/1.5 and 85/2, BTW.
Also, both ZK lenses work well wide open, close up and at infinity.
But the 85/2 has a minimum distance of 1.8m ...

Roland what you say is interesting. I have always assumed, like the talking dog (i.e. not that it spoke well but that it spoke at all) the classic fast lenses were great technical feats but not necessarily good wide open. I like the J-9 and Nikkor 105mm (in Contax mount)wide open but that is both because a bit of softness is good for portraiture as is throwing the background out of focus. I must say I haven't been blown away with the quality of the f1.5 50mm Sonnar (or J-3 copy) when used wide open and at close distances. Of course even tiny focusing errors blow resolution to hell.

Could this be a product of collimation – for what distance are your lenses optimized? In SLR mounts the 180mm Sonnar and other fast telephoto Sonnars are at there best wide open, but of course collimation with a RF is not an issue there. I think I may be missing something really good if collimation can make these fast lenses sing wide open.

Michael

 

[outfitter]

At infinity, it was best at F2.8.

Wow. Can you point me to any links that show how to optimize at 5M? What ws the quality at infinity when stopped down or is this lens a close up lens mostly?

Michael


PS I just remembered that I have a pre-war aftermarket coated f1.5/50mm Sonnar at HenryS for cleaning and adjustment - what working distance do you suggest I have him adjust it for? I frequently work from minimum focus to about 20 feet but I wouldn't like to ruin the lens for infinity work.

 

[ferider]

Roland what you say is interesting. I have always assumed, like the talking dog (i.e. not that it spoke well but that it spoke at all) the classic fast lenses were great technical feats but not necessarily good wide open. I like the J-9 and Nikkor 105mm (in Contax mount)wide open but that is both because a bit of softness is good for portraiture as is throwing the background out of focus. I must say I haven't been blown away with the quality of the f1.5 50mm Sonnar (or J-3 copy) when used wide open and at close distances. Of course even tiny focusing errors blow resolution to hell.

Could this be a product of collimation – for what distance are your lenses optimized? In SLR mounts the 180mm Sonnar and other fast telephoto Sonnars are at there best wide open, but of course collimation with a RF is not an issue there. I think I may be missing something really good if collimation can make these fast lenses sing wide open.

Michael

Hi Michael,

my lenses all work well close up and wide open. I showed some examples in this thread:

http://www.rangefinderforum.com/forums/showthread.php?t=34185

The Nikkor 50/1.4, 85/2, 105/2.5 and the Canon 50/1.5 are all well collimated
for minimum distance - they came like this. The Nikkor at f1.4 is obviously
optimized for this since it starts to vignette at f1.4 and more distant focus.

It took me a long time to find the ZK lenses, not for collection, but because I
believed that - in contrast to the later Jupiter lenses - the LTM ZK lenses
are calibrated to propper LTM standard and work well close up and open.
And the two lenses that I got confirmed this.

Shooting any of those lenses close up and open is not easy and requires
a well-calibrated camera and steady hands. With the longer lenses I
typically miss 1 to 2 out of 3 shots, even though I use a good M3. The
105/2.5 is the hardest one to focus.

You might say an SLR is easier to use for this purpose. Technically maybe
true. But I like the RF method, camera size, and quiet shutter exactly in
these applications. Plus, I love Sonnars.

Best,

Roland.

 

[outfitter]

Hi Michael,



Plus, I love Sonnars.

Best,

Roland.

Wow again - I missed that post. A new project to drive me crazy - wish I understood all the optical stuff better but I like you and Brian's results too much to let a little ignorance stop me.

BTW you don't have to forgo Sonnars in SLR. I have the following Sonnars in SLR mounts: CZJ 180mm f2.8 in P6 mount with adapters for 42mm, Nikon and QBM; Rollei 135mm Sonnar f2.8 QBM; CZJ f3.5 135mm Sonnar 42mm; and 85mm Sonnar f2,8 QBM

Michael

 

[40oz]

I already got a matching pair - LTM and Contax mount 🙂

Gotta say I like them. Not necessary for every shot, and f1.5 isn't always a good idea, but one nice thing is even the out of focus shots look pretty lol.

 

[outfitter]

I'll post a thread on adjusting the J-3's. I use a TTL viewer with a fairly big magnifier on it. You can also use a film strip across the film gate and use a loupe to adjust actual focus to agree with the RF of the camera. I start at 5m, check again at 3m. Then test with film wide-open and close-up. I have good luck with this ad-hoc method.

I have your instructions for adjusting the J3 LTM but I'm afraid to work on mine - too many drilling and tapping of holes. Adjusting my J3 in Contax mount seems to have its own world of complexity. I happen to have the rare Contax ground glass focusing screen that snaps into the film gate and the shimming of the Contax mount J3 seems simple enough; the problem seems to be with checking the rangefinder accuracy on the Contax/Kiev. Only the Contax IIa/Kiev 4 series have the tripod bushing in the body to mount the body for testing. The bad news is that if the rangefinder is off the internal adjustments involve major dissassembly of the camera rangefinder and related cams and gears. If I can find a later Zeiss or Kiev body in which the RF is dead on at least I can check the backfocus of the lenses using that body as a test fixture.

Michael