The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Leica Summilux-M 90mm F1.5 ASPH and the Leica Noctilux-M 75mm F1.25 ASPH for their suitability to various photography scenarios:
Size and Weight Comparison
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Below you can find a scaled side-by-side image of Leica Summilux-M 90mm F1.5 ASPH and Leica Noctilux-M 75mm F1.25 ASPH to get a better idea of how their sizes compare in real life.
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 Summilux-M 90mm F1.5 ASPH weighs 1010g, which means it is 45g (4%) lighter than the Leica Noctilux-M 75mm F1.25 ASPH which has a weight of 1055g.
Filter Threads
Both the Leica Summilux-M 90mm F1.5 ASPH and the Leica Noctilux-M 75mm F1.25 ASPH have the same Filter thread size of 67mm.
Below are links to the 67mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Leica Summilux-M 90mm F1.5 ASPH and the Leica Noctilux-M 75mm F1.25 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 Monochrome, Leica M11 and Leica M10.
Focal Range
Leica Summilux-M 90mm F1.5 ASPH is a prime lens with fixed focal lenght of 90mm.
On the other hand, the Leica Noctilux-M 75mm F1.25 ASPH is a prime lens with fixed focal lenght of 75mm.