The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 18-270mm f3.5-6.3 II PZD and the Sony DT 18-135mm F3.5-5.6 SAM 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. Tamron 18-270mm f3.5-6.3 II PZD is the longer of the two lenses at 88mm. The Sony DT 18-135mm F3.5-5.6 SAM with a length of 86mm, is 2mm shorter. On the other hand, the Sony DT 18-135mm F3.5-5.6 SAM has a larger diameter of 76mm compared to the Tamron 18-270mm f3.5-6.3 II PZD's 74mm 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. Sony DT 18-135mm F3.5-5.6 SAM weighs 398g, 11% (52g) lighter than the Tamron 18-270mm f3.5-6.3 II PZD's weight of 450g.
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 18-270mm f3.5-6.3 II PZD and the Sony DT 18-135mm F3.5-5.6 SAM has the same Sony Alpha lens mount. Some of the latest released cameras that are compatible with the Sony Alpha lenses are Sony A68, Sony A77 II and Sony A58.
Focal Range
Tamron 18-270mm f3.5-6.3 II PZD has a focal range of 18-270mm and 15.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-405mm when used on a APS-C / DX format camera. Sony DT 18-135mm F3.5-5.6 SAM has a focal range of 18-135mm and 7.5X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-202.5mm when used on a APS-C / DX format camera.