The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Viltrox 9mm F2.8 E and the Tamron 20mm 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. Tamron 20mm F2.8 Di III OSD M1:2 is the longer of the two lenses at 64mm. The Viltrox 9mm F2.8 E with a length of 56mm, is 8mm shorter. Besides being longer, the Tamron 20mm F2.8 Di III OSD M1:2 also has a larger diameter of 73mm compared to the Viltrox 9mm F2.8 E's 65mm 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. Viltrox 9mm F2.8 E weighs 175g, which means it is 45g (20%) lighter than the Tamron 20mm F2.8 Di III OSD M1:2 which has a weight of 220g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Sony E Mount for size comparison purposes.
Ultra-Wideangle Lenses in Sony E Mount for Size Comparison
Filter Threads
The Viltrox 9mm F2.8 E has a filter size of 58mm whereas the Tamron 20mm 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 Viltrox 9mm F2.8 E:
And these are the 67mm filters that we recommend for the Tamron 20mm F2.8 Di III OSD M1:2:
Lens Mounts
Both the Viltrox 9mm F2.8 E and the Tamron 20mm 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 ZV-E10 II, Sony A6700 and Sony FX30.
Focal Range
Viltrox 9mm F2.8 E is a prime lens with fixed focal lenght of 9mm which has an effective (full-frame 35mm equivalent) focal range of
13.5mm when used on a APS-C / DX format camera.
On the other hand, the Tamron 20mm F2.8 Di III OSD M1:2 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.
