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 600mm f4.0L IS USM 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 600mm f4.0L IS USM is the longer of the two lenses at 456mm. The Canon 16-35mm F2.8L III with a length of 128mm, is 328mm shorter. Besides being longer, the Canon 600mm f4.0L IS USM also has a larger diameter of 168mm compared to the Canon 16-35mm F2.8L III's 89mm diameter.
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 16-35mm F2.8L III weighs 790g, which means it is 4570g (85%) lighter than the Canon 600mm f4.0L IS USM which has a weight of 5360g.
Both the Canon 16-35mm F2.8L III and the Canon 600mm f4.0L IS USM has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
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 an 35mm (FF) equivalent of 25.6 - 56mm.
Canon 600mm f4.0L IS USM is a prime lens with fixed focal lenght of 600mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides an 35mm (FF) equivalent of 960mm.