The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Leica Summarit-M 35mm f2.5 and the Leica Elmarit-M 21mm f2.8 ASPH for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Leica Elmarit-M 21mm f2.8 ASPH is the longer of the two lenses at 46mm. The Leica Summarit-M 35mm f2.5 with a length of 34mm, is 12mm shorter. Besides being longer, the Leica Elmarit-M 21mm f2.8 ASPH also has a larger diameter of 58mm compared to the Leica Summarit-M 35mm f2.5's 51mm diameter.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Leica Summarit-M 35mm f2.5 weighs 220g, which means it is 80g (26%) lighter than the Leica Elmarit-M 21mm f2.8 ASPH which has a weight of 300g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Leica M Mount for size comparison purposes.
Wideangle Prime Lenses in Leica M Mount for Size Comparison
Both the Leica Summarit-M 35mm f2.5 and the Leica Elmarit-M 21mm f2.8 ASPH has the same Leica M lens mount. Some of the latest released cameras that are compatible with the Leica M lenses are Leica M11, Leica M10 and Leica M Typ 262.
Leica Summarit-M 35mm f2.5 is a prime lens with fixed focal lenght of 25-35mm. Leica Elmarit-M 21mm f2.8 ASPH is a prime lens with fixed focal lenght of 21mm.