The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Carl Zeiss Makro-Planar T2/100 and the Canon 100mm f2.8 Macro USM 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. Canon 100mm f2.8 Macro USM is the longer of the two lenses at 119mm. The Carl Zeiss Makro-Planar T2/100 with a length of 113mm, is 6mm shorter. Besides being longer, the Canon 100mm f2.8 Macro USM also has a larger diameter of 79mm compared to the Carl Zeiss Makro-Planar T2/100's 76mm 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. Canon 100mm f2.8 Macro USM weighs 600g, 11% (80g) lighter than the Carl Zeiss Makro-Planar T2/100's weight of 680g.
Below you can find the dimension and weight table of the Macro Prime Lenses in Canon EF Mount for size comparison purposes.
Macro Prime Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both the Carl Zeiss Makro-Planar T2/100 and the Canon 100mm f2.8 Macro USM has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Carl Zeiss Makro-Planar T2/100 is also available in Pentax KAF and Nikon F (FX) mounts.
Focal Range
Both lenses have the same focal range of 100mm but while Carl Zeiss Makro-Planar T2/100 has the fastest aperture of F2.0, the Canon 100mm f2.8 Macro USM's widest aperture value is F2.8.