The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Voigtlander 75mm F1.8 Heliar Classic and the Leica Summarit-M 75mm f2.5 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. Voigtlander 75mm F1.8 Heliar Classic is the longer of the two lenses at 74mm. The Leica Summarit-M 75mm f2.5 with a length of 61mm, is 13mm shorter. Besides being longer, the Voigtlander 75mm F1.8 Heliar Classic also has a larger diameter of 58mm compared to the Leica Summarit-M 75mm f2.5's 55mm 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 75mm f2.5 weighs 345g, 19% (82g) lighter than the Voigtlander 75mm F1.8 Heliar Classic's weight of 427g.
Below you can find the dimension and weight table of the Telephoto Prime Lenses in Leica M Mount for size comparison purposes.
Telephoto Prime Lenses in Leica M Mount for Size Comparison
Lens Mounts
Both the Voigtlander 75mm F1.8 Heliar Classic and the Leica Summarit-M 75mm 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 Monochrome, Leica M11 and Leica M10.
Focal Range
Both lenses have the same focal range of 75mm but while Voigtlander 75mm F1.8 Heliar Classic has the fastest aperture of F1.8, the Leica Summarit-M 75mm f2.5's widest aperture value is F2.5.