The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax 16-85mm F3.5-5.6 ED DC WR and the Pentax 18-55mm F3.5-5.6 AL 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. Pentax 16-85mm F3.5-5.6 ED DC WR is the longer of the two lenses at 94mm. The Pentax 18-55mm F3.5-5.6 AL WR with a length of 68mm, is 26mm shorter. Besides being longer, the Pentax 16-85mm F3.5-5.6 ED DC WR also has a larger diameter of 78mm compared to the Pentax 18-55mm F3.5-5.6 AL WR's 69mm 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 18-55mm F3.5-5.6 AL WR weighs 230g, 52% (258g) lighter than the Pentax 16-85mm F3.5-5.6 ED DC WR's weight of 488g.
Filter Threads
The Pentax 16-85mm F3.5-5.6 ED DC WR has a filter size of 72mm whereas the Pentax 18-55mm F3.5-5.6 AL WR 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 72mm filters that we recommend you to consider for the Pentax 16-85mm F3.5-5.6 ED DC WR:
And these are the 52mm filters that we recommend for the Pentax 18-55mm F3.5-5.6 AL WR:
Lens Mounts
The Pentax 16-85mm F3.5-5.6 ED DC WR has the Pentax KAF3 lens mount whereas the Pentax 18-55mm F3.5-5.6 AL WR has the Pentax KAF 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 KAF3 Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Focal Range
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.
On the other hand, the Pentax 18-55mm F3.5-5.6 AL WR has a focal range of 18-55mm and 3.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-82.5mm when used on a APS-C / DX format camera.