The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax DA 18-50mm F4.5-5.6 DC WR RE and the Tamron AF 28-80mm f3.5-5.6 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 DA 18-50mm F4.5-5.6 DC WR RE is the longer of the two lenses at 71mm. The Tamron AF 28-80mm f3.5-5.6 with a length of 70mm, is 1mm shorter. On the other hand, the Tamron AF 28-80mm f3.5-5.6 has a larger diameter of 72mm compared to the Pentax DA 18-50mm F4.5-5.6 DC WR RE's 41mm 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 DA 18-50mm F4.5-5.6 DC WR RE weighs 158g, which means it is 79g (33%) lighter than the Tamron AF 28-80mm f3.5-5.6 which has a weight of 237g.
Filter Threads
Both the Pentax DA 18-50mm F4.5-5.6 DC WR RE and the Tamron AF 28-80mm f3.5-5.6 have the same Filter thread size of 58mm.
Below are links to the 58mm filters that we recommend you to consider for these lenses:
Lens Mounts
The Pentax DA 18-50mm F4.5-5.6 DC WR RE has the Pentax KAF3 lens mount whereas the Tamron AF 28-80mm f3.5-5.6 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.
Tamron AF 28-80mm f3.5-5.6 is also available in Canon EF , Nikon F (FX) and Sony Alpha mounts.
Focal Range
Pentax DA 18-50mm F4.5-5.6 DC WR RE has a focal range of 18-50mm and
2.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27-75mm when used on a APS-C / DX format camera.
On the other hand, the Tamron AF 28-80mm f3.5-5.6 has a focal range of 28-80mm and 2.9X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 42 - 120mm.
