The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 70-300mm f4-5.6 LD and the Tamron AF 18-200mm f3.5-6.3 XR II LD 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. Tamron AF 70-300mm f4-5.6 LD is the longer of the two lenses at 117mm. The Tamron AF 18-200mm f3.5-6.3 XR II LD with a length of 84mm, is 33mm shorter. Besides being longer, the Tamron AF 70-300mm f4-5.6 LD also has a larger diameter of 77mm compared to the Tamron AF 18-200mm f3.5-6.3 XR 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 18-200mm f3.5-6.3 XR II LD weighs 398g, 8% (37g) lighter than the Tamron AF 70-300mm f4-5.6 LD's weight of 435g.
Filter Threads
Both the Tamron AF 70-300mm f4-5.6 LD and the Tamron AF 18-200mm f3.5-6.3 XR II LD 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
The Tamron AF 70-300mm f4-5.6 LD has the Nikon F (FX) lens mount whereas the Tamron AF 18-200mm f3.5-6.3 XR II LD has the Sony Alpha lens mount. Some of the latest released cameras that are compatible with these mounts are Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount and Sony A68, Sony A77 II and Sony A58 for the Sony Alpha Mount.
Tamron AF 70-300mm f4-5.6 LD is also available in the Canon EF , Sony Alpha and Pentax KAF mounts.
Tamron AF 18-200mm f3.5-6.3 XR II LD is also available in Canon EF , Nikon F (DX) and Pentax KAF mounts.
Focal Range
Tamron AF 70-300mm f4-5.6 LD has a focal range of 70-300mm and
4.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
105 - 450mm.
On the other hand, the Tamron AF 18-200mm f3.5-6.3 XR II LD 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.
