CV Nokton 40mm f/1.2 vs. 50mm f/1.2

[Bill Blackwell]

Has anyone done any real-world testing between the CV 40mm f/1.2 and the 50mm f/1.2? Other than the obvious extra room the 40 provides in the corners, are there any real differences in rendering between them?

I currently own the 40 -

All the above were recently shot with the 40mm Nokton f/1.2 (6-bit coded as a 50mm Noctilux f/1.2 [the new one]) on my M10-P. All but the last one (~70% of the original image) are uncropped full-frame.

 

[Bill Blackwell]

I can't believe no one but me has thought about this.

Stephen, what do you think?

 

[CameraQuest]

I can't believe no one but me has thought about this.

Stephen, what do you think?

real world they are the same lens, only different focal lengths.

However the 50/1.2 appeared later. Some consider it the best fast M 50 ever made.

 

[pyeh]

Bill, I hesitated to answer your question. I have both lenses and I think both are terrific. I haven't compared their images though, except enough to think that they render identically.
I bought the 40mm as a fast lens for my cameras with 40mm framelines, and I bought the 50mm to have a fast lens for my other rangefinders. I had the Voigtlander 50/1.1 years ago, but the 1.2 is in another league.

 

[Bill Blackwell]

Thanks, Guys. I appreciate your responses.

Real world they are the same lens, only different focal lengths. However the 50/1.2 appeared later. Some consider it the best fast M 50 ever made.

I've looked at every review I could find on both lenses and I have seen the "best 50" comment used more than once. But I've never seen a direct real-world comparison between the 40 and 50. Interestingly, I really didn't like the 40 at first; I couldn't find a 6-bit code that worked (I had the lens milled for it). As a Noctilux f/1 it was terrible - it vignetted at every stop and the files were blaa and lifeless. Then I moved to the Asph Summilux, which was better, but it still didn't really do it for me. But when I got hold of the 6-bit code of the new 50mm Noctilux f/1.2 I tried it right away and it works perfectly. I imagine it would do the same for the 50.

Bill, I hesitated to answer your question. I have both lenses and I think both are terrific. I haven't compared their images though, except enough to think that they render identically.
I bought the 40mm as a fast lens for my cameras with 40mm framelines, and I bought the 50mm to have a fast lens for my other rangefinders. I had the Voigtlander 50/1.1 years ago, but the 1.2 is in another league.

I owned more than one example of the Nokton f/1.1 and could never get along with it. I didn't like the bokeh and there was terrible focus shift (especially on close-ups) at the wider apertures. I bought the 40 as an "open box" with the shade at a very good price. As I indicated above, I struggled to make it work, but I'm very much enjoying it now.

I'm thinking there's no reason to have the 50 (my primary 50 is an Asph Summilux), but I wanted to see if someone would actually say so (from experience).

 

[pyeh]

Bill, for sure if you have other fast 50s that you like then no need to get the 50/1.2.
I too have other fast-enough 50s and a slew of slower ones and I reach for them before I use the 50/1.2, good as it is.
I think the 40mm is distinctive because there are so few 40mm lenses around, and with the CLEs I have it's tailor made. It doesn't even block the RF window, if you leave the hood off. On a full frame mirrorless camera 40mm is a useful in-between focal length for me, and on an APS-C mirrorless it's not too narrow.

 

[Bill Blackwell]

I purchased the 50mm f/1.2 at a good price some time back to compare with the 40mm f/1.2. I found the pincushion distortion out of the 50mm f/1.2 to be substantial (worse than the 40mm f/2). Both are terrible in this respect though. Otherwise I found no distinct difference in rendering between them other than the slightly more coverage of the 40mm f/1.2. I ultimately sold the 50mm f/1.2, but I still own and use the 40mm f/1.2.

CV 50mm Nokton f/1.2 - pincushion distortion.

 

[Ko.Fe.]

I assume it is about VM on M mount. If so, to me it mostly depends on framelines accuracy.
40 filed for 35mm frames is great on cameras with inaccurate 35 framelines.
For example, M9 series cameras, where f1.2 also makes old fashion practical sense on limited ISO range.