The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Irix 45mm F1.4 and the Canon 16-35mm f4L IS USM for their suitability to various photography scenarios:
Size and Weight Comparison
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 16-35mm f4L IS USM weighs 615g, 33% (310g) lighter than the Irix 45mm F1.4's weight of 925g.
Filter Threads
Both the Irix 45mm F1.4 and the Canon 16-35mm f4L 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
The Irix 45mm F1.4 has the Pentax KAF2 lens mount whereas the Canon 16-35mm f4L IS USM has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF2 Mount and Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K for the Canon EF Mount.
Irix 45mm F1.4 is also available in the Canon EF and Nikon F (FX) mounts.
Focal Range
Irix 45mm F1.4 is a prime lens with fixed focal lenght of 45mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
67.5mm.
On the other hand, the Canon 16-35mm f4L IS USM 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.
