It’s good to know lens limitations and flaws to make better pictures with it. 7artisans 35mm F1.2 is fast, so it is expected that F1.2 is soft.
When it comes to real shots, I’d use at least F2.8 for whole frame pictures, and F1.2-F2.0 range for center image objects.
F1.2 (purple fringing in the center)
F1.4 (still visible vignetting in the corners)
Barrel distortion of 7artisans 35mm F1.2 (shot at F2.8)
I like how 7artisans 35mm F1.2 performs in the center, and it just depends on the situation which aperture to use, F1.2-F2 is greatly working for many cases.
I think this lens will get actively used in the next few months : )
Landscape shots at F1.2 – F4 range
Here’s good example when F2.8-F4 is required to get better details in frame borders, otherwise it looks very distractive. For the landscape I’d always set at least F4 if I don’t plan to crop the frame.
Curvature + sharpness test
Here is the sequence of shots taken from a tripod at different apertures. I may be wrong but the lens may have slight focus-shift when changing aperture, so I’ve slightly refocused at the center for each image.
Borders and corners are almost roughly blurred at F1.2 – F2.8. The center is noticeably soft at F1.2-F1.4, which I like for portraits (and using Voigtlander 40mm F1.4 for that softness). I also see vignetting at F1.2-F2.0.
Samples below are resized to 1200px, you can look at full size here
Looks like F2.8 is a good point where most of the frame has acceptable sharpness variations for general shots.
You can also check live shot samples at public Flickr group 7artisans 35mm F1.2