The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Voigtlander 28mm F2 Ultron and the Leica Summarit-M 35mm f2.5 for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Voigtlander 28mm F2 Ultron is the longer of the two lenses at 51mm. The Leica Summarit-M 35mm f2.5 with a length of 34mm is 17mm shorter. Besides being longer, the Voigtlander 28mm F2 Ultron also has a larger diameter of 55mm compared to Leica Summarit-M 35mm f2.5's 51mm diameter.
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, 9% (24g) lighter than the Voigtlander 28mm F2 Ultron's weight of 244g.
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 Voigtlander 28mm F2 Ultron and Leica Summarit-M 35mm f2.5 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.
Voigtlander 28mm F2 Ultron is a prime lens with fixed focal lenght of 28mm. Leica Summarit-M 35mm f2.5 is a prime lens with fixed focal lenght of 25-35mm.