The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 10-20mm F3.5 EX DC HSM and the Pentax 12-24mm F4.0 ED AL 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. Sigma 10-20mm F3.5 EX DC HSM is the longer of the two lenses at 88mm. The Pentax 12-24mm F4.0 ED AL with a length of 84mm, is 4mm shorter. On the other hand, the Pentax 12-24mm F4.0 ED AL has a larger diameter of 88mm compared to the Sigma 10-20mm F3.5 EX DC HSM's 87mm 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 12-24mm F4.0 ED AL weighs 430g, 17% (90g) lighter than the Sigma 10-20mm F3.5 EX DC HSM's weight of 520g.
Filter Threads
The Sigma 10-20mm F3.5 EX DC HSM has a filter size of 82mm whereas the Pentax 12-24mm F4.0 ED AL 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 82mm filters that we recommend you to consider for the Sigma 10-20mm F3.5 EX DC HSM:
And these are the 77mm filters that we recommend for the Pentax 12-24mm F4.0 ED AL:
Lens Mounts
The Sigma 10-20mm F3.5 EX DC HSM has the Pentax KAF3 lens mount whereas the Pentax 12-24mm F4.0 ED AL has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are , and for the Pentax KAF3 Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Sigma 10-20mm F3.5 EX DC HSM is also available in the Canon EF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Sigma 10-20mm F3.5 EX DC HSM has a focal range of 10-20mm and
2.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
15-30mm when used on a APS-C / DX format camera.
On the other hand, the Pentax 12-24mm F4.0 ED AL has a focal range of 12-24mm and 2.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 18-36mm when used on a APS-C / DX format camera.
