The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Zeiss Otus 1.4/55 and the Sigma 50mm F1.4 DG HSM A for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Zeiss Otus 1.4/55 is the longer of the two lenses at 141mm. The Sigma 50mm F1.4 DG HSM A with a length of 100mm is 41mm shorter. Besides being longer, the Zeiss Otus 1.4/55 also has a larger diameter of 92mm compared to Sigma 50mm F1.4 DG HSM A's 85mm 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. Sigma 50mm F1.4 DG HSM A weighs 815g, 15% (155g) lighter than the Zeiss Otus 1.4/55's weight of 970g.
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 Zeiss Otus 1.4/55 and Sigma 50mm F1.4 DG HSM A 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.
Zeiss Otus 1.4/55 is also available in Nikon F (FX) mount.
Sigma 50mm F1.4 DG HSM A is also available in Sony Alpha , Sigma SA, Nikon F (FX) and Leica L mounts.
Zeiss Otus 1.4/55 is a prime lens with fixed focal lenght of 55mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides an 35mm (FF) equivalent of 88mm.
Sigma 50mm F1.4 DG HSM A is a prime lens with fixed focal lenght of 50mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides an 35mm (FF) equivalent of 80mm.