The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 16-35mm F2.8L III and the Canon 10-18mm f4.5-5.6 IS STM 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. Canon 16-35mm F2.8L III is the longer of the two lenses at 128mm. The Canon 10-18mm f4.5-5.6 IS STM with a length of 72mm, is 56mm shorter. Besides being longer, the Canon 16-35mm F2.8L III also has a larger diameter of 89mm compared to the Canon 10-18mm f4.5-5.6 IS STM's 75mm 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. Canon 10-18mm f4.5-5.6 IS STM weighs 240g, 69% (550g) lighter than the Canon 16-35mm F2.8L III's weight of 790g.
Filter Threads
The Canon 16-35mm F2.8L III has a filter size of 82mm whereas the Canon 10-18mm f4.5-5.6 IS STM has a 67mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 82mm filters that we recommend you to consider for the Canon 16-35mm F2.8L III:
And these are the 67mm filters that we recommend for the Canon 10-18mm f4.5-5.6 IS STM:
Lens Mounts
The Canon 16-35mm F2.8L III has the Canon EF lens mount whereas the Canon 10-18mm f4.5-5.6 IS STM has the Canon EF-S lens mount. Some of the latest released cameras that are compatible with these mounts are Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K for the Canon EF Mount and Canon T8i, Canon 90D and Canon SL3 for the Canon EF-S Mount.
Focal Range
Canon 16-35mm F2.8L III has a focal range of 16-35mm and
2.2X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
25.6 - 56mm.
On the other hand, the Canon 10-18mm f4.5-5.6 IS STM has a focal range of 10-18mm and 1.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 16-28.8mm when used on a APS-C / DX format camera.
