The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax 17-70mm F4.0 AL SDM and the Canon 24-105mm f4L 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 24-105mm f4L IS USM is the longer of the two lenses at 107mm. The Pentax 17-70mm F4.0 AL SDM with a length of 94mm, is 13mm shorter. Besides being longer, the Canon 24-105mm f4L IS USM also has a larger diameter of 84mm compared to the Pentax 17-70mm F4.0 AL SDM's 75mm 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. Pentax 17-70mm F4.0 AL SDM weighs 485g, which means it is 185g (27%) lighter than the Canon 24-105mm f4L IS USM which has a weight of 670g.
Filter Threads
The Pentax 17-70mm F4.0 AL SDM has a filter size of 67mm whereas the Canon 24-105mm f4L IS USM has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Pentax 17-70mm F4.0 AL SDM:
And these are the 77mm filters that we recommend for the Canon 24-105mm f4L IS USM:
Lens Mounts
The Pentax 17-70mm F4.0 AL SDM has the Pentax KAF3 lens mount whereas the Canon 24-105mm f4L IS USM has the Canon EF lens mount. Some of the latest released cameras that are compatible with these mounts are , and for the Pentax KAF3 Mount and Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K for the Canon EF Mount.
Focal Range
Pentax 17-70mm F4.0 AL SDM has a focal range of 17-70mm and
4.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
25.5-105mm when used on a APS-C / DX format camera.
On the other hand, the Canon 24-105mm f4L IS USM 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.
