The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 28-300mm f3.5-6.3 VC PZD and the Sigma 18-50mm F2.8-4.5 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. Tamron 28-300mm f3.5-6.3 VC PZD is the longer of the two lenses at 96mm. The Sigma 18-50mm F2.8-4.5 DC OS HSM with a length of 89mm, is 7mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 74mm.
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 18-50mm F2.8-4.5 DC OS HSM weighs 395g, 26% (145g) lighter than the Tamron 28-300mm f3.5-6.3 VC PZD's weight of 540g.
Filter Threads
Both the Tamron 28-300mm f3.5-6.3 VC PZD and the Sigma 18-50mm F2.8-4.5 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
The Tamron 28-300mm f3.5-6.3 VC PZD has the Nikon F (FX) lens mount whereas the Sigma 18-50mm F2.8-4.5 DC OS HSM 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 28-300mm f3.5-6.3 VC PZD is also available in the Canon EF and Sony Alpha mounts.
Sigma 18-50mm F2.8-4.5 DC OS HSM is also available in Canon EF , Pentax KAF3, Sony Alpha and Sigma SA mounts.
Focal Range
Tamron 28-300mm f3.5-6.3 VC PZD 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 Sigma 18-50mm F2.8-4.5 DC OS HSM has a focal range of 18-50mm and 2.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-75mm when used on a APS-C / DX format camera.
