The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Kamlan 28mm F1.4 and the Sigma 30mm F2.8 EX DN 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. Kamlan 28mm F1.4 is the longer of the two lenses at 65mm. The Sigma 30mm F2.8 EX DN with a length of 39mm, is 26mm shorter. On the other hand, the Sigma 30mm F2.8 EX DN has a larger diameter of 61mm compared to the Kamlan 28mm F1.4's 55mm 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 F2.8 EX DN weighs 135g, 64% (249g) lighter than the Kamlan 28mm F1.4's weight of 384g.
Filter Threads
The Kamlan 28mm F1.4 has a filter size of 52mm whereas the Sigma 30mm F2.8 EX DN has a 46mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 52mm filters that we recommend you to consider for the Kamlan 28mm F1.4:
And these are the 46mm filters that we recommend for the Sigma 30mm F2.8 EX DN:
Lens Mounts
Both the Kamlan 28mm F1.4 and the Sigma 30mm F2.8 EX DN 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.
Kamlan 28mm F1.4 is also available in Canon EF-M , Fujifilm X and Micro Four Thirds mounts.
Sigma 30mm F2.8 EX DN is also available in Micro Four Thirds mount.
Focal Range
Kamlan 28mm F1.4 is a prime lens with fixed focal lenght of 28mm which has an effective (full-frame 35mm equivalent) focal range of
42mm when used on a APS-C / DX format camera.
On the other hand, the Sigma 30mm F2.8 EX DN 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.