It has 9 elements in 8 groups and 2 APD elements but no Asph elements. It is a pretty classic sonnar design.
It is a quite different design than the 50 f/1.2 for full frame mounts (Cosina makes that lens for Leica M, and Sony E mounts). I am using the Sony E mount version. I have had this lens for years, but recently got the SE version which is lighter and cannot be declicked for video and that is what I am using. I like the lens a lot, and have enjoyed using it on Sony. This lens has 8 element in 6 groups with 2 aspherical elements and 1 APD elements. It is not really a sonnar design and closer to a double gauss but it looks to me a bit like the Leica M 50 f/1.4 Asph as well. It is bigger lens. I will be comparing it to the Fuji shooting it in APS-C crop mode on Sony. You can see the specifics on it at the Cosina website here:
Since these lenses are going to be shot on an APS-C camera and a FF camera in crop mode I want to compare them to a somewhat similar lens on FF Sony. I have the Voigtlander 75 f/1.5 in Leica M mount which has the same field of view on FF as these 50 f/1.2 lenses shot on APS-C. The 75 f/1.5 bit bigger entrance pupil and therefore can create shallower depth of field (DOF) wide open, but only by about half a stop. I will compare the lenses wide open and that with as similar of entrance pupils/DOF as I can. I will compare at f/1.2 vs. f/1.5; f/1.4 vs. f/2; f/2 vs. f/2.8; and f/2.8 vs. f/4. This lens has 7 elements in 6 groups with 1 aspherical element and 3 APD elements. It is to my eye mostly a sonnar design, but perhaps less so of one than the 50 f/1.2 for Fuji X mount. I shot this lens with the TTartisans coded Leica M to Sony E mount adapter set to 75mm so I should have gotten IBIS with the correct focal length set. You can see the specifics on it at the Cosina website here:
Here are the measured weights of the lens bare without any caps or hoods and a picture of the lenses so you can see the size comparison better.
Voigtlander 50 f/1.2 for Fuji X mount (CVX 50): 287g
Voigtlander 50 f/1.2 SE for Sony E mount (CVE 50): 382g
Voigtlander 75 f/1.5 for Leica M with TT artisans adapter (CVM 75): 379g
When I shot these I used the Voigtlander specified hood for the CVX 50 and CVM 75, and on the CVE 50 I used the hood for the CVX.
p.1 #2 · A comparison of the Voitlander lenses (50 f/1.2 for Fuji X mount with 50 f/1.2 for Sony E mount cropped and 75 f/1.5 for Leica M
I decided to shoot a plastic bust with strong side light (it is window light) and some back light in front of a window with some foliage in the background. It was on a small table in our sunroom. It is a fairly ugly bust, but is pretty much head sized. It does not have a lot of detail on the surface. I will give close ups of the focus area (the left eye of the bust) and the bokeh to the right of the bust as you face it. I did my best to try to keep the magnification the same in the comparison which was a little tricky given the different pixel densities and using APS-C and FF 35mm. Note for the close ups they are pixel level on the CVX 50, to keep magnification the same I downscaled the CVM 75 shots and upscaled the CVE 50 shots.
I also used the metering of the Sony camera (I am using an A7r V) to set shutter speed (they were all shot at ISO 125, the base ISO of the Fuji). Then matched that on the Fuji. This means the CVM shots were underexposed, so I adjusted that in post when I brought them into Photoshop effectively turning up the ISO on the CVM shots. I did not disable the profile corrections on the either 50 and as an adapted lens the CVM 75 did not have profile correction (I suppose I could have enable that in post, but I didn't). Auto WB generated very different WB between the cameras, but I like the Fuji WB better so the used the Kelvin for that for all shots.
Importantly all of these are shot handheld and were cropped a bit to straighten my crooked handholding so when sizing the closeup they are never exact. For this type of shooting (of people at fairly close distances) I would also shoot handheld, so I decided to do that for the test even if it adds a bit of randomness to the shots. I also obviously use manual focus and I took three shots each time and picked the best one. I really didn't find it hard to obtain focus with any of the lenses, however.
Here are the wide open comparisons. First the whole scene, then the close up of the focus points, then the close ups of the bokeh.
X-T5VOIGTLANDER NOKTON 50mm F1.2 lens50mmf/1.21/1000s125 ISO0.0 EV
ILCE-7RM5Voigtlander NOKTON 50mm F1.2 Aspherical lens50mmf/1.21/1000s125 ISO0.0 EV
ILCE-7RM5Leica M 75mm F1.0 lens75mmf/1.01/800s125 ISO0.0 EV
X-T5VOIGTLANDER NOKTON 50mm F1.2 lens50mmf/2.01/500s125 ISO0.0 EV
ILCE-7RM5Voigtlander NOKTON 50mm F1.2 Aspherical lens50mmf/1.21/1000s125 ISO0.0 EV
X-T5VOIGTLANDER NOKTON 50mm F1.2 lens50mmf/1.21/1000s125 ISO0.0 EV
ILCE-7RM5Voigtlander NOKTON 50mm F1.2 Aspherical lens50mmf/1.21/1000s125 ISO0.0 EV
p.1 #10 · A comparison of the Voitlander lenses (50 f/1.2 for Fuji X mount with 50 f/1.2 for Sony E mount cropped and 75 f/1.5 for Leica M
Here is my take after these samples and using the lenses side by side for a couple of days. I may very well change my views as I use the lenses more.
First, I think all three lenses are useable for portraits and interestingly they all have quite nice and fairly similar bokeh. Maybe I will see differences in bokeh over time, but I am not seeing much right now. The differences are more in the plane of focus.
Second, the CVX 50 f/1.2 has quite a bit of uncorrected spherical aberrations resulting in less sharpness and contrast at the focus point and especially so at these distances. It is fairly well corrected for axial CA, however, and that may be because spherical aberrations help mask it. I think I will be quite happy with this lens as a dual purpose lens with quite a bit of character at wider apertures, but nice sharpness across the frame stopped down. I still need to check the stopped down performance more, however. It is also wonderfully smaller, yet with really nice ergonomics.
Third, the CVM 75 f/1.5 is quite a bit sharper at equivalent depth of field at the focus point than the other two lenses. It may be just that it has a slower aperture at equivalent depth of field, but from f/2 it is nice and sharp at the focus point. It also handles axial CA really well in most situations. It is bigger, however, and I don't see big differences from the other lenses unless I really pixel peep. It also has the worst ergonomics by a fair margin, IMO. So I am torn. I can see the better performance, but only if I look really closely. Is it worth carrying a bigger lens that isn't as good ergonomically for that difference? I am not sure.
Fourth, the CVE 50 f/1.2 cropped to APS-C to my eyes has a bit more axial CA and isn't quite as sharp at f/1.2, f/1.4, and f/1.6 in the focus plane than the CVX 50 f/1.2, but seems to be sharpening up across the frame a bit better at f/2 and f/2.8. I like it the least of the three but only by a small margin. I don't think I would use it to replace one of the other two, but it is nice to know that it could be used quite effectively as it is shot in these samples.
That is my take for now. I would love to hear any thoughts that any one might have.
p.1 #11 · A comparison of the Voitlander lenses (50 f/1.2 for Fuji X mount with 50 f/1.2 for Sony E mount cropped and 75 f/1.5 for Leica M
Thanks for doing this. I was about to write that I don't have any experience with any of these, but it seems I'm about to. I happened to come upon a mint CVX 50/1.2 on my lunch break, browsing the used section online, for a nearby store.
I've had my eye on it for years, but now the price was low enough I'd feel silly for not picking it up.
