The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Voigtlander 21mm F1.8 Ultron and the Carl Zeiss Biogon T2,8/21 ZM for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Voigtlander 21mm F1.8 Ultron is the longer of the two lenses at 92mm. The Carl Zeiss Biogon T2,8/21 ZM with a length of 75mm, is 17mm shorter. Besides being longer, the Voigtlander 21mm F1.8 Ultron also has a larger diameter of 62mm compared to the Carl Zeiss Biogon T2,8/21 ZM's 53mm diameter.
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. Carl Zeiss Biogon T2,8/21 ZM weighs 280g, 32% (132g) lighter than the Voigtlander 21mm F1.8 Ultron's weight of 412g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Leica M Mount for size comparison purposes.
Wideangle Lenses in Leica M Mount for Size Comparison
Filter Threads
The Voigtlander 21mm F1.8 Ultron has a filter size of 58mm whereas the Carl Zeiss Biogon T2,8/21 ZM has a 46mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Voigtlander 21mm F1.8 Ultron:
And these are the 46mm filters that we recommend for the Carl Zeiss Biogon T2,8/21 ZM:
Lens Mounts
Both the Voigtlander 21mm F1.8 Ultron and the Carl Zeiss Biogon T2,8/21 ZM has the same Leica M lens mount. Some of the latest released cameras that are compatible with the Leica M lenses are Leica M EV1, Leica M11-D and Pixii Max.
Focal Range
Both lenses have the same focal range of
21mm but while Voigtlander 21mm F1.8 Ultron has the fastest aperture of
F1.8, the Carl Zeiss Biogon T2,8/21 ZM's widest aperture value is
F2.8.
