The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 28-75mm f2.8 XR LD and the Sony DT 18-55mm F3.5-5.6 SAM II 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 28-75mm f2.8 XR LD is the longer of the two lenses at 92mm. The Sony DT 18-55mm F3.5-5.6 SAM II with a length of 69mm, is 23mm shorter. Besides being longer, the Tamron AF 28-75mm f2.8 XR LD also has a larger diameter of 73mm compared to the Sony DT 18-55mm F3.5-5.6 SAM II's 72mm 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. Sony DT 18-55mm F3.5-5.6 SAM II weighs 222g, 56% (288g) lighter than the Tamron AF 28-75mm f2.8 XR LD's weight of 510g.
Below you can find the dimension and weight table of the Standard Zoom Lenses in Sony Alpha Mount for size comparison purposes.
Standard Lenses in Sony Alpha Mount for Size Comparison
Filter Threads
The Tamron AF 28-75mm f2.8 XR LD has a filter size of 67mm whereas the Sony DT 18-55mm F3.5-5.6 SAM II has a 55mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Tamron AF 28-75mm f2.8 XR LD:
And these are the 55mm filters that we recommend for the Sony DT 18-55mm F3.5-5.6 SAM II:
Lens Mounts
Both the Tamron AF 28-75mm f2.8 XR LD and the Sony DT 18-55mm F3.5-5.6 SAM II 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 28-75mm f2.8 XR LD is also available in Canon EF , Nikon F (FX) and Pentax KAF mounts.
Focal Range
Tamron AF 28-75mm f2.8 XR LD has a focal range of 28-75mm and
2.7X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
42 - 112.5mm.
On the other hand, the Sony DT 18-55mm F3.5-5.6 SAM II has a focal range of 18-55mm and 3.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-82.5mm when used on a APS-C / DX format camera.