The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Fujifilm 18-55mm F2.8-4 R LM OIS and the OM System 12-40mm F2.8 PRO II 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 12-40mm F2.8 PRO II is the longer of the two lenses at 84mm. The Fujifilm 18-55mm F2.8-4 R LM OIS with a length of 70mm, is 14mm shorter. Besides being longer, the OM System 12-40mm F2.8 PRO II also has a larger diameter of 70mm compared to the Fujifilm 18-55mm F2.8-4 R LM OIS's 65mm diameter.
Below you can find a scaled side-by-side image of Fujifilm 18-55mm F2.8-4 R LM OIS and OM System 12-40mm F2.8 PRO II to get a better idea of how their sizes compare in real life.
Comparison image of the Fujifilm 18-55mm F2.8-4 R LM OIS and the OM System 12-40mm F2.8 PRO II Size and Weight 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. Fujifilm 18-55mm F2.8-4 R LM OIS weighs 310g, which means it is 72g (18%) lighter than the OM System 12-40mm F2.8 PRO II which has a weight of 382g.
Filter Threads
The Fujifilm 18-55mm F2.8-4 R LM OIS has a filter size of 58mm whereas the OM System 12-40mm F2.8 PRO II has a 62mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Fujifilm 18-55mm F2.8-4 R LM OIS:
And these are the 62mm filters that we recommend for the OM System 12-40mm F2.8 PRO II:
Lens Mounts
The Fujifilm 18-55mm F2.8-4 R LM OIS has the Fujifilm X lens mount whereas the OM System 12-40mm F2.8 PRO II has the Micro Four Thirds lens mount . Some of the latest released cameras that are compatible with these mounts are Fujifilm X-T30 III , Fujifilm X-E5 and Fujifilm X-M5 for the Fujifilm X Mount and OM System OM-3 Astro , OM System OM-5 II and OM System OM-3 for the Micro Four Thirds Mount.
Focal Range
Fujifilm 18-55mm F2.8-4 R LM OIS has a focal range of 18-55mm and
3.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27-82.5mm when used on a APS-C / DX format camera.
On the other hand, the OM System 12-40mm F2.8 PRO II has a focal range of 12-40mm and 3.3X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 24-80mm when used on a FourThirds format camera.
