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 VC LD and the Sigma 18-125mm F3.8-5.6 DC OS HSM 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. Sigma 18-125mm F3.8-5.6 DC OS HSM is the longer of the two lenses at 89mm. The Tamron AF 28-300mm f3.5-6.3 XR VC LD with a length of 78mm, is 11mm shorter. On the other hand, the Tamron AF 28-300mm f3.5-6.3 XR VC LD has a larger diameter of 99mm compared to the Sigma 18-125mm F3.8-5.6 DC OS HSM'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. Sigma 18-125mm F3.8-5.6 DC OS HSM weighs 490g, 11% (65g) lighter than the Tamron AF 28-300mm f3.5-6.3 XR VC LD's weight of 555g.
Below you can find the dimension and weight table of the SuperZoom Lenses in Canon EF Mount for size comparison purposes.
Superzoom Lenses in Canon EF Mount for Size Comparison
Filter Threads
Both the Tamron AF 28-300mm f3.5-6.3 XR VC LD and the Sigma 18-125mm F3.8-5.6 DC OS HSM have the same Filter thread size of 67mm.
Below are links to the 67mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Tamron AF 28-300mm f3.5-6.3 XR VC LD and the Sigma 18-125mm F3.8-5.6 DC OS HSM has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K.
Tamron AF 28-300mm f3.5-6.3 XR VC LD is also available in the Nikon F (FX) mount.
Sigma 18-125mm F3.8-5.6 DC OS HSM is also available in Sigma SA and Nikon F (DX) mounts.
Focal Range
Tamron AF 28-300mm f3.5-6.3 XR VC LD has a focal range of 28-300mm and
10.7X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
44.8 - 480mm.
On the other hand, the Sigma 18-125mm F3.8-5.6 DC OS HSM has a focal range of 18-125mm and 6.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 28.8-200mm when used on a APS-C / DX format camera.
