The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax 10-17mm F3.5-4.5 ED Fisheye and the Canon 8-15mm f4L Fisheye 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 8-15mm f4L Fisheye USM is the longer of the two lenses at 83mm. The Pentax 10-17mm F3.5-4.5 ED Fisheye with a length of 72mm, is 11mm shorter. Besides being longer, the Canon 8-15mm f4L Fisheye USM also has a larger diameter of 79mm compared to the Pentax 10-17mm F3.5-4.5 ED Fisheye's 68mm 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 10-17mm F3.5-4.5 ED Fisheye weighs 320g, which means it is 220g (40%) lighter than the Canon 8-15mm f4L Fisheye USM which has a weight of 540g.
Lens Mounts
The Pentax 10-17mm F3.5-4.5 ED Fisheye has the Pentax KAF lens mount whereas the Canon 8-15mm f4L Fisheye 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 KAF 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 10-17mm F3.5-4.5 ED Fisheye has a focal range of 10-17mm and
1.7X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
15-25.5mm when used on a APS-C / DX format camera.
On the other hand, the Canon 8-15mm f4L Fisheye USM has a focal range of 8-15mm and 1.9X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 12.8 - 24mm.
