The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 12mm f1.4 and the Tamron 11-20mm F2.8 RF 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 11-20mm F2.8 RF is the longer of the two lenses at 84mm. The Sigma 12mm f1.4 with a length of 67mm, is 17mm shorter. Besides being longer, the Tamron 11-20mm F2.8 RF also has a larger diameter of 73mm compared to the Sigma 12mm f1.4's 69mm 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 12mm f1.4 weighs 250g, which means it is 90g (26%) lighter than the Tamron 11-20mm F2.8 RF which has a weight of 340g.
Filter Threads
The Sigma 12mm f1.4 has a filter size of 62mm whereas the Tamron 11-20mm F2.8 RF has a 67mm 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 Sigma 12mm f1.4:
And these are the 67mm filters that we recommend for the Tamron 11-20mm F2.8 RF:
Lens Mounts
Both the Sigma 12mm f1.4 and the Tamron 11-20mm F2.8 RF has the same Canon RF lens mount. Some of the latest released cameras that are compatible with the Canon RF lenses are RED Komodo-X 6K, RED Komodo 6K and Canon EOS C70.
Sigma 12mm f1.4 is also available in the Sony E and Fujifilm X mounts.
Focal Range
Sigma 12mm f1.4 is a prime lens with fixed focal lenght of 12mm which has an effective (full-frame 35mm equivalent) focal range of
18mm when used on a APS-C / DX format camera.
On the other hand, the Tamron 11-20mm F2.8 RF has a focal range of 11-20mm and 1.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 17.6-32mm when used on a APS-C / DX format camera.
