The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 28-300mm f3.5-6.3 XR LD and the Sigma 18-200mm F3.5-6.3 DC OS HSM C 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 18-200mm F3.5-6.3 DC OS HSM C is the longer of the two lenses at 86mm. The Tamron AF 28-300mm f3.5-6.3 XR LD with a length of 84mm, is 2mm shorter. On the other hand, the Tamron AF 28-300mm f3.5-6.3 XR LD has a larger diameter of 73mm compared to the Sigma 18-200mm F3.5-6.3 DC OS HSM C's 71mm 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. Tamron AF 28-300mm f3.5-6.3 XR LD weighs 420g, which means it is 10g (2%) lighter than the Sigma 18-200mm F3.5-6.3 DC OS HSM C which has a weight of 430g.
Below you can find the dimension and weight table of the SuperZoom Lenses in Sony Alpha Mount for size comparison purposes.
Superzoom Lenses in Sony Alpha Mount for Size Comparison
Filter Threads
Both the Tamron AF 28-300mm f3.5-6.3 XR LD and the Sigma 18-200mm F3.5-6.3 DC OS HSM C have the same Filter thread size of 62mm.
Below are links to the 62mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Tamron AF 28-300mm f3.5-6.3 XR LD and the Sigma 18-200mm F3.5-6.3 DC OS HSM C has the same Sony Alpha lens mount. Some of the latest released cameras that are compatible with the Sony Alpha lenses are Sony A99 II, Sony A68 and Sony A77 II.
Tamron AF 28-300mm f3.5-6.3 XR LD is also available in the Canon EF , Nikon F (FX) and Pentax KAF mounts.
Sigma 18-200mm F3.5-6.3 DC OS HSM C is also available in Canon EF , Nikon F (DX), Pentax KAF3 and Sigma SA mounts.
Focal Range
Tamron AF 28-300mm f3.5-6.3 XR LD has a focal range of 28-300mm and
10.7X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
42 - 450mm.
On the other hand, the Sigma 18-200mm F3.5-6.3 DC OS HSM C has a focal range of 18-200mm and 11.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-300mm when used on a APS-C / DX format camera.
