The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 28-200mm f3.8-5.6 XR and the Sony DT 18-250mm F3.5-6.3 for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Sony DT 18-250mm F3.5-6.3 is the longer of the two lenses at 86mm. The Tamron AF 28-200mm f3.8-5.6 XR with a length of 75mm, is 11mm shorter. Besides being longer, the Sony DT 18-250mm F3.5-6.3 also has a larger diameter of 75mm compared to the Tamron AF 28-200mm f3.8-5.6 XR's 71mm diameter.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Tamron AF 28-200mm f3.8-5.6 XR weighs 354g, which means it is 86g (19%) lighter than the Sony DT 18-250mm F3.5-6.3 which has a weight of 440g.
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
Lens Mounts
Both the Tamron AF 28-200mm f3.8-5.6 XR and the Sony DT 18-250mm F3.5-6.3 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 28-200mm f3.8-5.6 XR is also available in Canon EF , Nikon F (FX) and Pentax KAF mounts.
Focal Range
Tamron AF 28-200mm f3.8-5.6 XR has a focal range of 28-200mm and 7.1X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 42 - 300mm.
Sony DT 18-250mm F3.5-6.3 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.