The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Leica Thambar-M 90mm F2.2 and the Leica APO 75mm f2 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 Thambar-M 90mm F2.2 is the longer of the two lenses at 90mm. The Leica APO 75mm f2 ASPH with a length of 67mm, is 23mm shorter. On the other hand, the Leica APO 75mm f2 ASPH has a larger diameter of 58mm compared to the Leica Thambar-M 90mm F2.2's 57mm 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 APO 75mm f2 ASPH weighs 430g, 14% (70g) lighter than the Leica Thambar-M 90mm F2.2's weight of 500g.
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 Leica Thambar-M 90mm F2.2 and the Leica APO 75mm f2 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.
Focal Range
Leica Thambar-M 90mm F2.2 is a prime lens with fixed focal lenght of 90mm. Leica APO 75mm f2 ASPH is a prime lens with fixed focal lenght of 75mm.