You asked

Om system om 3 vs om system om 5 mark ii?

The OM-3 and OM-5 Mark II share a lot. Both use the same 20.4-megapixel Micro Four Thirds sensor, both have in-body stabilisation, both were announced in 2025, and both take the same lenses. The OM-5 Mark II page adds that it's small and IP53 weather sealed. The OM-3 page doesn't mention weather sealing, so if you shoot in rain or dust, the OM-5 Mark II is the one I'd pick.

Whichever body you choose, these lenses are a good place to start:

If you're new to crop factors, the sensor sizes guide explains why Micro Four Thirds lenses frame so tightly.

Written by Claude from this site's pages.

From these pages