The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Leica APO-SL 35mm F2 ASPH and the Leica Summicron-M 28mm f2 ASPH 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. Leica APO-SL 35mm F2 ASPH is the longer of the two lenses at 102mm. The Leica Summicron-M 28mm f2 ASPH with a length of 41mm, is 61mm shorter. Besides being longer, the Leica APO-SL 35mm F2 ASPH also has a larger diameter of 73mm compared to the Leica Summicron-M 28mm f2 ASPH's 53mm 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 Summicron-M 28mm f2 ASPH weighs 270g, 62% (450g) lighter than the Leica APO-SL 35mm F2 ASPH's weight of 720g.
Filter Threads
The Leica APO-SL 35mm F2 ASPH has a filter size of 67mm whereas the Leica Summicron-M 28mm f2 ASPH 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 67mm filters that we recommend you to consider for the Leica APO-SL 35mm F2 ASPH:
And these are the 46mm filters that we recommend for the Leica Summicron-M 28mm f2 ASPH:
Lens Mounts
The Leica APO-SL 35mm F2 ASPH has the Leica L lens mount whereas the Leica Summicron-M 28mm f2 ASPH has the Leica M lens mount. Some of the latest released cameras that are compatible with these mounts are Leica SL3-P, Panasonic S1 II and Panasonic S1 IIE for the Leica L Mount and Leica M EV1, Leica M11-D and Pixii Max for the Leica M Mount.
Focal Range
Leica APO-SL 35mm F2 ASPH is a prime lens with fixed focal lenght of 35mm.
On the other hand, the Leica Summicron-M 28mm f2 ASPH is a prime lens with fixed focal lenght of 28mm.