The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 18-300 F3.5-6.3 DC OS HSM and the Pentax 16-85mm F3.5-5.6 ED DC WR 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 18-300 F3.5-6.3 DC OS HSM is the longer of the two lenses at 102mm. The Pentax 16-85mm F3.5-5.6 ED DC WR with a length of 94mm, is 8mm shorter. Besides being longer, the Sigma 18-300 F3.5-6.3 DC OS HSM also has a larger diameter of 79mm compared to the Pentax 16-85mm F3.5-5.6 ED DC WR's 78mm diameter.
Below you can find a scaled side-by-side image of Sigma 18-300 F3.5-6.3 DC OS HSM and Pentax 16-85mm F3.5-5.6 ED DC WR to get a better idea of how their sizes compare in real life.
Comparison image of the Sigma 18-300 F3.5-6.3 DC OS HSM and the Pentax 16-85mm F3.5-5.6 ED DC WR Size and Weight 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 16-85mm F3.5-5.6 ED DC WR weighs 488g, 16% (97g) lighter than the Sigma 18-300 F3.5-6.3 DC OS HSM's weight of 585g.
Filter Threads
Both the Sigma 18-300 F3.5-6.3 DC OS HSM and the Pentax 16-85mm F3.5-5.6 ED DC WR have the same Filter thread size of 72mm .
Below are links to the 72mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Sigma 18-300 F3.5-6.3 DC OS HSM and the Pentax 16-85mm F3.5-5.6 ED DC WR has the same Pentax KAF3 lens mount . Some of the latest released cameras that are compatible with the Pentax KAF3 lenses are Pentax K-3 III Mono , Pentax KF and Pentax K-3 III .
Canon EF , Nikon F (DX) , Sigma SA and Sony Alpha mounts.
Focal Range
Sigma 18-300 F3.5-6.3 DC OS HSM has a focal range of 18-300mm and
16.7X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27-450mm when used on a APS-C / DX format camera.
On the other hand, the Pentax 16-85mm F3.5-5.6 ED DC WR has a focal range of 16-85mm and 5.3X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 24-127.5mm when used on a APS-C / DX format camera.
