Solutions/settings in PL if no optical module exists?

A question about optical modules: How do you deal with it when you use lenses for which there are no modules in PhotoLab(7)? What corrections do you make manually?

And a question I’ve never really thought about: What about RAW converters that don’t provide correction modules for lenses at all?


When a camera is used with an unsupported lens, the respective tools are still present but partially greyed out:

  • Vignetting
  • Lens Softness Correction
  • Chromatic Aberration
  • Distortion

You can then decide to try manual corrections or leave things be. After all, not all images need straight lines, e.g. landscapes and portraits … depending on how good or bad the lens is. Check capture below for partially disabled tools and metadata entries. Distance 50 yards.

(Equivalent focal length ca. 500mm)

Thank you very much for your answer.
I wonder why DxO deactivates Lens Softness Correction. Maybe it can only be used properly with known lens data.
I’m curious: why didn’t you use USM?

Lens Softness Correction is specially designed for use with a module. Imagine some field curvature, which can e.g. produce a ring of sharpness and softer edges and centre. LSC will selectively sharpen the softer areas and leave the sharp areas mostly alone.

I disabled USM in order to see what the image looks like with minimal optical intervention. As we can see with the tiles in the lower lefthand area of the screen capture, the lens is no slouch at all, even though it’s at least 40 years old. Mamiya lenses had an excellent reputation then - and using only the centre portion helped too.

M645 lenses are built for image circles of at least 70mm. Using it on a full frame camera with an image circle of about 42mm results in a crop factor of about 1.67 and the potentially softer edges and corners are not captured by the sensor. Downside: Manually focusing is not easy because DSLR screens are not optimised for it and focus peeking is not precise enough in a DSLR. Mirrorless might be a better option for precise focusing.

Thank you for the explanation of Lens Softness Correction.

Yes, I suspected that this may have been the reason for not using USM.
I know Mamiya medium format cameras and lenses, they really had/have a good reputation. These lenses used with 35mm cameras bring undoubted advantages. It’s similar to using a Nikon FX lens on a Nikon DX camera - only the center part of the lens reaches the Sensr and the peripheral areas are left out.

The goal (for an image) isn’t necessarily a kind of engineered perfection - rather, an emotional character or verity may take precedence. As none of my lenses produce any exif data, I only ‘correct’ their results on an ad-hoc basis. For example, I won’t correct distortion (barrel, pincushion …) unless I feel that it causes psychological discomfort relative to certain straight lines in a particular image. Neither am I much bothered by vignetting. You can accept many things as part of the character of a given lens and actually enjoy them. I will usually try to curb excessive chromatic aberration because it tends to ugliness. Etc …

Yes, of course, I understand what you mean. Fortunately, this one lens, which is not and will not be supported by DxO, is a lens that I use 99% of the time to photograph animals. So the lack of a correction module shouldn’t play a major role.