The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 400mm f5.6L USM and the Canon 100-400mm f4.5-5.6L IS USM 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 400mm f5.6L USM is the longer of the two lenses at 257mm. The Canon 100-400mm f4.5-5.6L IS USM with a length of 189mm, is 68mm shorter. On the other hand, the Canon 100-400mm f4.5-5.6L IS USM has a larger diameter of 92mm compared to the Canon 400mm f5.6L USM's 90mm 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 400mm f5.6L USM weighs 1250g, which means it is 130g (9%) lighter than the Canon 100-400mm f4.5-5.6L IS USM which has a weight of 1380g.
Filter Threads
Both the Canon 400mm f5.6L USM and the Canon 100-400mm f4.5-5.6L IS USM have the same Filter thread size of 77mm.
Below are links to the 77mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Canon 400mm f5.6L USM and the Canon 100-400mm f4.5-5.6L IS USM has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K.
Focal Range
Canon 400mm f5.6L USM is a prime lens with fixed focal lenght of 400mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
640mm.
On the other hand, the Canon 100-400mm f4.5-5.6L IS USM has a focal range of 100-400mm and 4.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 160 - 640mm.
