You asked

Om system m zuiko 90mm f 3 5 macro is pro vs olympus m zuiko 60mm f 2 8 macro?

Both lenses are macro lenses for Micro Four Thirds, and both work on every camera in their lists, including the OM System OM-1. The difference is reach and steadiness.

The OM System M.Zuiko 90mm f/3.5 Macro IS PRO frames like 180mm on full frame and reaches 2x magnification. It's stabilised and weather-sealed, so I'd pick it for insects, flowers, and anything you can't get close to without spooking it.

The Olympus M.Zuiko 60mm f/2.8 Macro frames like 120mm and has no stabilisation. It's the better choice when you want to work closer to your subject, and its wider f/2.8 aperture gives you more light and a shallower background.

For a full breakdown of how the crop factor changes depth of field, see the focal length converter.

Written by Claude from this site's pages.

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