The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 21mm F1.4 ED AS UMC CS and the Tamron 24mm F2.8 Di III OSD M1:2 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 21mm F1.4 ED AS UMC CS is the longer of the two lenses at 68mm. The Tamron 24mm F2.8 Di III OSD M1:2 with a length of 64mm, is 4mm shorter. On the other hand, the Tamron 24mm F2.8 Di III OSD M1:2 has a larger diameter of 73mm compared to the Samyang 21mm F1.4 ED AS UMC CS 's 64mm 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 24mm F2.8 Di III OSD M1:2 weighs 215g, 21% (60g) lighter than the Samyang 21mm F1.4 ED AS UMC CS 's weight of 275g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Sony E Mount for size comparison purposes.
Wideangle Lenses in Sony E Mount for Size Comparison
Filter Threads
The Samyang 21mm F1.4 ED AS UMC CS has a filter size of 58mm whereas the Tamron 24mm F2.8 Di III OSD M1:2 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 58mm filters that we recommend you to consider for the Samyang 21mm F1.4 ED AS UMC CS :
And these are the 67mm filters that we recommend for the Tamron 24mm F2.8 Di III OSD M1:2:
Lens Mounts
Both the Samyang 21mm F1.4 ED AS UMC CS and the Tamron 24mm F2.8 Di III OSD M1:2 has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony A6700, Sony FX30 and Sony ZV-E10.
Samyang 21mm F1.4 ED AS UMC CS is also available in Canon EF-M , Fujifilm X and Micro Four Thirds mounts.
Focal Range
Samyang 21mm F1.4 ED AS UMC CS is a prime lens with fixed focal lenght of 21mm which has an effective (full-frame 35mm equivalent) focal range of
31.5mm when used on a APS-C / DX format camera.
On the other hand, the Tamron 24mm F2.8 Di III OSD M1:2 is a prime lens with fixed focal lenght of 24mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 36mm.