The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 24-105mm F3.5-5.6 IS STM and the Canon 35-80mm f4.0-5.6 III 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 F3.5-5.6 IS STM is the longer of the two lenses at 104mm. The Canon 35-80mm f4.0-5.6 III with a length of 64mm, is 40mm shorter. Besides being longer, the Canon 24-105mm F3.5-5.6 IS STM also has a larger diameter of 83mm compared to the Canon 35-80mm f4.0-5.6 III's 65mm 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 35-80mm f4.0-5.6 III weighs 175g, 66% (350g) lighter than the Canon 24-105mm F3.5-5.6 IS STM's weight of 525g.
Below you can find the dimension and weight table of the Standard Zoom Lenses in Canon EF Mount for size comparison purposes.
Standard Lenses in Canon EF Mount for Size Comparison
Filter Threads
The Canon 24-105mm F3.5-5.6 IS STM has a filter size of 77mm whereas the Canon 35-80mm f4.0-5.6 III has a 52mm 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 F3.5-5.6 IS STM:
And these are the 52mm filters that we recommend for the Canon 35-80mm f4.0-5.6 III:
Lens Mounts
Both the Canon 24-105mm F3.5-5.6 IS STM and the Canon 35-80mm f4.0-5.6 III 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.
Focal Range
Canon 24-105mm F3.5-5.6 IS STM 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 Canon 35-80mm f4.0-5.6 III has a focal range of 35-80mm and 2.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 56 - 128mm.