The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 24-105mm F4L IS II and the Tamron 45mm F1.8 Di VC USD 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 24-105mm F4L IS II is the longer of the two lenses at 118mm. The Tamron 45mm F1.8 Di VC USD with a length of 92mm, is 26mm shorter. Besides being longer, the Canon 24-105mm F4L IS II also has a larger diameter of 84mm compared to the Tamron 45mm F1.8 Di VC USD's 80mm 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. Tamron 45mm F1.8 Di VC USD weighs 540g, 32% (255g) lighter than the Canon 24-105mm F4L IS II's weight of 795g.
Filter Threads
The Canon 24-105mm F4L IS II has a filter size of 77mm whereas the Tamron 45mm F1.8 Di VC USD 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 77mm filters that we recommend you to consider for the Canon 24-105mm F4L IS II:
And these are the 67mm filters that we recommend for the Tamron 45mm F1.8 Di VC USD:
Lens Mounts
Both the Canon 24-105mm F4L IS II and the Tamron 45mm F1.8 Di VC USD 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.
Tamron 45mm F1.8 Di VC USD is also available in Nikon F (FX) and Sony Alpha mounts.
Focal Range
Canon 24-105mm F4L IS II has a focal range of 24-105mm and
4.4X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
38.4 - 168mm.
On the other hand, the Tamron 45mm F1.8 Di VC USD is a prime lens with fixed focal lenght of 45mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 72mm.