The type of photography that you are planning to use is an important decision factor. Here we have evaluated the OM System 90mm F3.5 Macro and the Olympus ED 75mm f1.8 for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. OM System 90mm F3.5 Macro is the longer of the two lenses at 136mm. The Olympus ED 75mm f1.8 with a length of 69mm, is 67mm shorter. Besides being longer, the OM System 90mm F3.5 Macro also has a larger diameter of 70mm compared to the Olympus ED 75mm f1.8's 64mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Olympus ED 75mm f1.8 weighs 305g, 32% (148g) lighter than the OM System 90mm F3.5 Macro's weight of 453g.
Filter Threads
The OM System 90mm F3.5 Macro has a filter size of 62mm whereas the Olympus ED 75mm f1.8 has a 58mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 62mm filters that we recommend you to consider for the OM System 90mm F3.5 Macro:
And these are the 58mm filters that we recommend for the Olympus ED 75mm f1.8:
Lens Mounts
Both the OM System 90mm F3.5 Macro and the Olympus ED 75mm f1.8 has the same Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with the Micro Four Thirds lenses are OM System OM-1 II, Panasonic G9 II and OM System OM-5.
Focal Range
OM System 90mm F3.5 Macro is a prime lens with fixed focal lenght of 90mm which has an effective (full-frame 35mm equivalent) focal range of
180mm when used on a FourThirds format camera.
On the other hand, the Olympus ED 75mm f1.8 is a prime lens with fixed focal lenght of 75mm which has an effective (full-frame 35mm equivalent) focal range of 150mm when used on a FourThirds format camera.