Lens review

OM System M.Zuiko Digital ED 90 mm f/3.5 Macro IS PRO

8 February 2023
Maciej Latałło

11. Summary


  • shapely, solid, and weather-sealed casing,
  • very good image quality in the frame centre,
  • good image quality on the edge of the frame,
  • slight longitudinal chromatic aberration,
  • low lateral chromatic aberration,
  • lack of problems with spherical aberration,
  • negligible distortion,
  • properly corrected coma,
  • very low astigmatism,
  • decent vignetting correction,
  • efficient optical stabilization,
  • sensible out-of-focus areas.


  • weak cooperation with the MC-20 teleconverter,
  • too slow aperture that makes it impossible to use the possibilities of the system to the full.
It is not my task to get smart and tell photographic companies how they should conduct their business. Still, it's a fact that the imagining division of Olympus was never a very profitable one and finally was sold to Japan Industrial Partners and they created a new company, OM Digital Solutions. Obviously something went wrong and, as mistakes had been made, you might wonder what these were.

If you ask me, I think the major mistake was that Olympus had never leveraged the potential of the smaller sensor. Employing a smaller detector provides you some assets and some liabilities. When it comes to the assets, there is a possibility of constructing small, lightweight lenses that are also faster and better corrected on the edges than their full frame equivalents.

I did expect that the Olympus system would be filled with f/0.8-f/1.4 instruments whereas during six years of the existence the fastest lenses, offered by them had an aperture of f/1.8.

Please Support Us

If you enjoy our reviews and articles, and you want us to continue our work please, support our website by donating through PayPal. The funds are going to be used for paying our editorial team, renting servers, and equipping our testing studio; only that way we will be able to continue providing you interesting content for free.

- - - - - - - - - - - - - - - - - advertisement - - - - - - - - - - - - - - - - -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Now the system has a new owner but it seems the conclusions haven't been drawn at all. In times when such macro lenses as the Sigma 180 mm f/2.8 APO Macro EX DG OS HSM, have been launched, OM Digital Solutions offers us a macro device with the same focal length equivalent but with an f/3.5 apperture.

If you can construct a good f/2.8 macro lens I don't doubt that you can also offer an f/2.0 macro lens equally efficient for the Micro 4/3 system which would be, additionally, significantly smaller and lighter. After all, such macro lenses designed for smaller sensors aren't that rare – it's enough you mention here the well-thought-out Tamron SP AF 60 mm f/2.0 Di II LD (IF) Macro 1:1, designed for APS-C/DX class detectors.

Still, the OMDS company decided to present an f/3.5 macro lens and the consequences of such a decision are brutal, mainly because of the laws of optics. Now you should remind yourself of a chart from the build quality chapter that showed clearly that the effecitve aperture for the 1:1 scale amounts to f/6.3 and for the 2:1 scale is only f/8.0.

Our resolution test showed clearly that the lens has to be closed down by 1-1.5 EV to reach the peak of its performance. It means that the macro scale and the maximum performance needs an effective aperture f/8-11 so you will have to tolerate just decent resolution values near 55-65 lpmm at most. They are very far from record values amounting to 95-100 lpmm that are possible to achieve in the Micro 4/3 system.

In other words, the decision of using the f/3.5 aperture means potential users will profit from only a bit over a half of resolution that can be offered by this system.

Another misconception is a recommendation for photographers to attach the OM System M.Zuiko Digital ED 90 mm f/3.5 Macro IS PRO to a teleconverter. We are tempted by an impressive 4:1 mapping scale but nobody mentions the fact that working in its proximity you can count on the maximum effective aperture of f/16. By f/16 the Micro 4/3 system is simply useless because it provides resolution on a level of just 40-42 lpmm. Indeed, even such values are unattainable because it's a diffraction limit for this aperture. Meanwhile for this set it constitutes the maximum relative aperture which has to be closed down by 1-3 EV in order to achieve the peak of the performance. It means in turn you would have to employ f/22-45 apertures which are completely useless in the case of the Micro 4/3 system.

I don't doubt that a macro lens, designed for the Micro 4/3 system, that is supposed to offer better mappings than 1:1 should be faster than its full frame equivalents. Unfortunately OM Digital Solutions copy mistakes of Olympus and consequently offer slower lenses, destroying all possible assets of the use of a smaller sensor. I fail to understand such a policy...

When it comes to the tested model, so the OM System M.Zuiko Digital ED 90 mm f/3.5 Macro IS PRO, it performed exactly as we expected, delivering good quality images up from the maximum relative aperture, very good on slight stopping down. Its parameters didn't allow it to do more but we've already covered that topic...