The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 50mm F1.4 AS UMC and the Tamron 45mm 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. Tamron 45mm F1.8 Di VC USD is the longer of the two lenses at 92mm. The Samyang 50mm F1.4 AS UMC with a length of 75mm, is 17mm shorter. On the other hand, the Samyang 50mm F1.4 AS UMC has a larger diameter of 82mm compared to the Tamron 45mm 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 45mm F1.8 Di VC USD weighs 520g, 2% (15g) lighter than the Samyang 50mm F1.4 AS UMC's weight of 535g.
Below you can find the dimension and weight table of the Standard Prime Lenses in Nikon F (FX) Mount for size comparison purposes.
Standard Lenses in Nikon F (FX) Mount for Size Comparison
Filter Threads
The Samyang 50mm F1.4 AS UMC has a filter size of 77mm whereas the Tamron 45mm 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 50mm F1.4 AS UMC:
And these are the 67mm filters that we recommend for the Tamron 45mm F1.8 Di VC USD:
Lens Mounts
Both the Samyang 50mm F1.4 AS UMC and the Tamron 45mm 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 50mm F1.4 AS UMC is also available in Canon EF , Pentax KAF, Sony Alpha and Sony E mounts.
Tamron 45mm F1.8 Di VC USD is also available in Canon EF and Sony Alpha mounts.
Focal Range
Samyang 50mm F1.4 AS UMC is a prime lens with fixed focal lenght of 50mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
75mm.
On the other hand, the Tamron 45mm F1.8 Di VC USD is a prime lens with fixed focal lenght of 45mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 67.5mm.