The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 20mm F1.8 and the Tamron 35mm F1.8 Di VC USD 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. Samyang 20mm F1.8 is the longer of the two lenses at 88mm. The Tamron 35mm F1.8 Di VC USD with a length of 81mm, is 7mm shorter. Besides being longer, the Samyang 20mm F1.8 also has a larger diameter of 83mm compared to the Tamron 35mm F1.8 Di VC USD's 80mm 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. Tamron 35mm F1.8 Di VC USD weighs 450g, 9% (47g) lighter than the Samyang 20mm F1.8's weight of 497g.
Filter Threads
The Samyang 20mm F1.8 has a filter size of 77mm whereas the Tamron 35mm F1.8 Di VC USD 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 77mm filters that we recommend you to consider for the Samyang 20mm F1.8:
And these are the 67mm filters that we recommend for the Tamron 35mm F1.8 Di VC USD:
Lens Mounts
Both the Samyang 20mm F1.8 and the Tamron 35mm F1.8 Di VC USD has the same Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (FX) lenses are Nikon D6, Nikon D780 and Nikon D3500.
Samyang 20mm F1.8 is also available in Canon EF , Canon EF-M, Fujifilm X, Micro Four Thirds, Pentax KAF, Samsung NX, Sony Alpha and Sony E mounts.
Tamron 35mm F1.8 Di VC USD is also available in Canon EF and Sony Alpha mounts.
Focal Range
Samyang 20mm F1.8 is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
30mm.
On the other hand, the Tamron 35mm F1.8 Di VC USD is a prime lens with fixed focal lenght of 35mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 52.5mm.