The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Leica SL 100mm F2.8 and the Sigma 135mm F1.8 DG HSM A 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. Sigma 135mm F1.8 DG HSM A is the longer of the two lenses at 139mm. The Leica SL 100mm F2.8 with a length of 137mm, is 2mm shorter. Besides being longer, the Sigma 135mm F1.8 DG HSM A also has a larger diameter of 91mm compared to the Leica SL 100mm F2.8'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. Leica SL 100mm F2.8 weighs 801g, which means it is 329g (29%) lighter than the Sigma 135mm F1.8 DG HSM A which has a weight of 1130g.
Below you can find the dimension and weight table of the Telephoto Prime Lenses in Leica L Mount for size comparison purposes.
Telephoto Lenses in Leica L Mount for Size Comparison
Filter Threads
The Leica SL 100mm F2.8 has a filter size of 67mm whereas the Sigma 135mm F1.8 DG HSM A has a 82mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Leica SL 100mm F2.8:
And these are the 82mm filters that we recommend for the Sigma 135mm F1.8 DG HSM A:
Lens Mounts
Both the Leica SL 100mm F2.8 and the Sigma 135mm F1.8 DG HSM A has the same Leica L lens mount. Some of the latest released cameras that are compatible with the Leica L lenses are Leica SL3-P, Panasonic S1 II and Panasonic S1 IIE.
Focal Range
Leica SL 100mm F2.8 is a prime lens with fixed focal lenght of 100mm.
On the other hand, the Sigma 135mm F1.8 DG HSM A is a prime lens with fixed focal lenght of 135mm.
