The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 18-250mm f3.5-6.3 II LD and the Sigma 18-200mm f3.5-6.3 II DC OS HSM 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 II DC OS HSM is the longer of the two lenses at 88mm. The Tamron AF 18-250mm f3.5-6.3 II LD with a length of 84mm, is 4mm shorter. Besides being longer, the Sigma 18-200mm f3.5-6.3 II DC OS HSM also has a larger diameter of 75mm compared to the Tamron AF 18-250mm f3.5-6.3 II LD's 74mm 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 18-250mm f3.5-6.3 II LD weighs 430g, which means it is 60g (12%) lighter than the Sigma 18-200mm f3.5-6.3 II DC OS HSM which has a weight of 490g.
Filter Threads
Both the Tamron AF 18-250mm f3.5-6.3 II LD and the Sigma 18-200mm f3.5-6.3 II DC OS HSM 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 18-250mm f3.5-6.3 II LD and the Sigma 18-200mm f3.5-6.3 II DC OS HSM has the same Nikon F (DX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (DX) lenses are Nikon D3500, Nikon D7500 and Nikon D5600.
Tamron AF 18-250mm f3.5-6.3 II LD is also available in the Canon EF , Sony Alpha and Pentax KAF mounts.
Sigma 18-200mm f3.5-6.3 II DC OS HSM is also available in Canon EF and Sigma SA mounts.
Focal Range
Tamron AF 18-250mm f3.5-6.3 II LD has a focal range of 18-250mm and
13.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27-375mm when used on a APS-C / DX format camera.
On the other hand, the Sigma 18-200mm f3.5-6.3 II DC OS HSM 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.
