Street Photography

I have just bought a Leica M4 for general use as I Do mostly street photography and can't decide on a Summicron 35 mm Or A Summicron C 40 mm I feel the 40 is a better choice Any ideas.?

Well, you'll either need to estimate the frame lines or buy an add on viewfinder for the 40. Good lens though.

Both good...IMHO small difference between the two. Flip a coin if you can't narrow down the choice otherwise. I'd personally go for the 35, but perhaps that's because I used one for so many years. OTOH the 40 more closely approximates the human eyes' field of view, which is probably why in the 1950-60s many Japanese cameras used 41-42.5mm for their fixed lens cameras.

Definitely get the 35mm. As others have said, the Leica M4 lacks 40mm framelines, so you'll either have to estimate the frame or attach an auxiliary viewfinder. But the more important factor is that the 40mm Summicron lens won't focus accurately on the M4, except by accident. The 40mm and 90mm lenses designed for the Leica CL camera have different rangefinder cams than other M-mount lenses. Although other M-mount lenses can focus accurately on a Leica CL, the reverse isn't true. At small apertures, depth of field may hide the focus error, but it will likely be a problem at wide apertures and close distances.

 

You will always hear some people say their 40mm or 90mm CL lenses work fine on other M-series cameras, but it's just luck. Sometimes the cams match, sometimes they don't. You can find a technical explanation elsewhere. Bottom line: Get the 35mm.

You will always hear some people say their 40mm or 90mm CL lenses work fine on other M-series cameras, but it's just luck. Sometimes the cams match, sometimes they don't. You can find a technical explanation elsewhere.

 

The haphazardness is a result of the (different) designs of the rangefinder coupling on these two lenses.

 

The 40mm and the 90mm lenses, designed to work with the CL, couple to the rangefinders’ arm via a Pitched Cam.

 

As far as I understand, all other M and LTM lenses have a Parallel Cam.

 

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I also believe that although the 40mm filter thread is 39mm dia., it has 0.75mm pitch, meaning that ‘normal’ 39mm Filters do not mate perfectly and there is risk of damaging the threads, the Leica “Series 5.5 Filters” are designed to be used with these lenses.

 

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Apropos the Framelines: some folk have filed a bit off the lens to accommodate alignment with the existing 35mm Framelines of the Camera.

 

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Bottom line: I also would get the 35mm.

 

WW

Supposedly but I have an old CL with the 40/2 and I have used it on my M2, M8, M9 and M10 and maybe there is some subtle focusing problem but it seems to do all right. And I've used my 50/2 summicron (not a C lens) on the CL and that worked fine too. I think a lot of people think the whole cam shape thing was just a Leica ploy to keep you from buying the cheaper C lenses and using them instead of their more expensive M lines.

I'd consider the 40mm M-Rokkor rather than the 40mm Summicron-C. It has the usual M focusing cam and is therefore a better match on a "real" M Leica. Also it has a normal filter thread not the Germanic series style with the retaining ring. Also it's cheaper but equal or better in performance.

I think a lot of people think the whole cam shape thing was just a Leica ploy to keep you from buying the cheaper C lenses and using them instead of their more expensive M lines.

 

Agree. But that doesn't deny the fact that the cams are different and thus the movement is different.

 

I'm not arguing: was simply providing the engineering background/rationale.

 

And although I have not that first hand experience with that 40mm lens on a Leica M, I also agree that (assuming there is indeed a focus problem - which I believe that there must be) it would be difficult to nail down in general day to day shooting.

 

What I mean is we'd assume that most "day to day" shots would be pulled around F/4~F/5.6 or smaller with the Main Subject at 3 metres or farther: how could you pick that focus error.

 

If F/2 were to be used, then (using back of an envelope calculations) you'd need to be framing something like an Head and Shoulders to a Tight Head Shot (around 500mm SD) to create a DoF to easily recognize that something was amiss - THEN of course if the two different Cams' Slopes/Separations were equal, at that close focus distance - I reckon there would be no error.

 

WW