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 Tamron AF 18-200mm f3.5-6.3 XR II LD for their suitability to various photography scenarios:
Size and Weight Comparison
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, 5% (22g) lighter than the Tamron AF 28-300mm f3.5-6.3 XR LD's weight of 420g.
Filter Threads
Both the Tamron AF 28-300mm f3.5-6.3 XR 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 28-300mm f3.5-6.3 XR LD has the Nikon F (FX) lens mount whereas the Tamron AF 18-200mm f3.5-6.3 XR II LD has the Nikon F (DX) 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 Nikon D3500, Nikon D7500 and Nikon D5600 for the Nikon F (DX) Mount.
Tamron AF 28-300mm f3.5-6.3 XR 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 , Sony Alpha and Pentax KAF 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 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.
