The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon RF 135mm F1.8 L IS USM and the Sony FE 135mm F1.8 GM for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Canon RF 135mm F1.8 L IS USM is the longer of the two lenses at 130mm. The Sony FE 135mm F1.8 GM with a length of 127mm, is 3mm shorter. On the other hand, the Sony FE 135mm F1.8 GM has a larger diameter of 90mm compared to the Canon RF 135mm F1.8 L IS USM's 89mm diameter.
Below you can find a scaled side-by-side image of Canon RF 135mm F1.8 L IS USM and Sony FE 135mm F1.8 GM to get a better idea of how their sizes compare in real life.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Canon RF 135mm F1.8 L IS USM weighs 935g, which means it is 15g (1%) lighter than the Sony FE 135mm F1.8 GM which has a weight of 950g.
The Canon RF 135mm F1.8 L IS USM has the Canon RF lens mount whereas the Sony FE 135mm F1.8 GM has the Sony E lens mount. Some of the latest released cameras that are compatible with these mounts are Canon R8, Canon R50 and Canon R6 II for the Canon RF Mount and Sony A7R V, Sony FX30 and Sony A7 IV for the Sony E Mount.
Both lenses have the same focal range of 135mm and the fastest aperture of F1.8.