With its “PRO” designation, this lens is designed for
enthusiast and professional underwater photographers. Knowing of the x2 crop factor of OM Digital Solutions cameras, a 180mm (90x2) effective focal lenght could
deliver the "big difference".

Constructed from 18 elements, arranged in 13 groups, the lens features a stabilization system that works together with OM System and Olympus camera bodies to delivers up to 7 steps of compensation via 5-axis sync image stabilisation.
The lens also features an acceleration sensor on the lens that detects motion
blur for correction of shift (so they say), which might have a positive impact on macro shooting.

The M.Zuiko 90mm F3.5 Macro IS PRO weighs a 453g and measures just 5.4" long by 2.7" diameter (136mm x 70mm). A minimum focus distance of 8.8" (22.4cm) means a working distance of around three inches (8cm) from the end of the lens, thus giving enough room for proper lightning when trying to shoot the most tiny critters.