The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 30mm F1.4 EX DC HSM 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. Tamron 35mm F1.8 Di VC USD is the longer of the two lenses at 81mm. The Sigma 30mm F1.4 EX DC HSM with a length of 59mm, is 22mm shorter. Besides being longer, the Tamron 35mm F1.8 Di VC USD also has a larger diameter of 80mm compared to the Sigma 30mm F1.4 EX DC HSM's 77mm 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 30mm F1.4 EX DC HSM weighs 430g, which means it is 20g (4%) lighter than the Tamron 35mm F1.8 Di VC USD which has a weight of 450g.
Filter Threads
The Sigma 30mm F1.4 EX DC HSM has a filter size of 62mm 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 62mm filters that we recommend you to consider for the Sigma 30mm F1.4 EX DC HSM:
And these are the 67mm filters that we recommend for the Tamron 35mm F1.8 Di VC USD:
Lens Mounts
Both the Sigma 30mm F1.4 EX DC HSM and the Tamron 35mm F1.8 Di VC USD has the same Sony Alpha lens mount. Some of the latest released cameras that are compatible with the Sony Alpha lenses are Sony A68, Sony A77 II and Sony A58.
Sigma 30mm F1.4 EX DC HSM is also available in Canon EF-S , Nikon F (DX), Four Thirds, Pentax KAF and Sigma SA mounts.
Tamron 35mm F1.8 Di VC USD is also available in Canon EF and Nikon F (FX) mounts.
Focal Range
Sigma 30mm F1.4 EX DC HSM is a prime lens with fixed focal lenght of 30mm which has an effective (full-frame 35mm equivalent) focal range of
45mm when used on a APS-C / DX format camera.
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.