The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron AF 70-300mm f4-5.6 LD and the Sigma 50-200mm F4-5.6 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. Tamron AF 70-300mm f4-5.6 LD is the longer of the two lenses at 117mm. The Sigma 50-200mm F4-5.6 DC OS HSM with a length of 102mm, is 15mm shorter. Besides being longer, the Tamron AF 70-300mm f4-5.6 LD also has a larger diameter of 77mm compared to the Sigma 50-200mm F4-5.6 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 50-200mm F4-5.6 DC OS HSM weighs 420g, 3% (15g) lighter than the Tamron AF 70-300mm f4-5.6 LD's weight of 435g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Canon EF Mount for size comparison purposes.
Telephoto Lenses in Canon EF Mount for Size Comparison
Filter Threads
The Tamron AF 70-300mm f4-5.6 LD has a filter size of 62mm whereas the Sigma 50-200mm F4-5.6 DC OS HSM 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 62mm filters that we recommend you to consider for the Tamron AF 70-300mm f4-5.6 LD:
And these are the 55mm filters that we recommend for the Sigma 50-200mm F4-5.6 DC OS HSM:
Lens Mounts
Both the Tamron AF 70-300mm f4-5.6 LD and the Sigma 50-200mm F4-5.6 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 Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Tamron AF 70-300mm f4-5.6 LD is also available in Nikon F (FX) , Sony Alpha and Pentax KAF mounts.
Sigma 50-200mm F4-5.6 DC OS HSM is also available in Pentax KAF3 , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Tamron AF 70-300mm f4-5.6 LD has a focal range of 70-300mm and
4.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
112 - 480mm.
On the other hand, the Sigma 50-200mm F4-5.6 DC OS HSM has a focal range of 50-200mm and 4.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 80-320mm when used on a APS-C / DX format camera.