Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Carl Zeiss Planar T1,4/50 is the longer of the two lenses at 69mm. The Canon 50mm f1.4 USM with a length of 51mm is 18mm shorter. On the other hand, the Canon 50mm f1.4 USM has a larger diameter of 74mm compared to Carl Zeiss Planar T1,4/50's 66mm diameter.
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 50mm f1.4 USM weighs 290g, 17% (60g) lighter than the Carl Zeiss Planar T1,4/50's weight of 350g.
Below you can find the dimension and weight table of the 'Standard Prime Lenses in Canon EF Mount for size comparison purposes.
Standard Prime Lenses in Canon EF Mount for Size Comparison
Both Carl Zeiss Planar T1,4/50 and Canon 50mm f1.4 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 Planar T1,4/50 is also available in Pentax KAF and Nikon F (FX) mounts.
Both lenses have the same focal range of 50mm and the fastest aperture of F1.4.