Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Zeiss Batis 40mm F2 CF is the longer of the two lenses at 93mm. The Sony FE 35mm F1.8 with a length of 73mm is 20mm shorter. Besides being longer, the Zeiss Batis 40mm F2 CF also has a larger diameter of 91mm compared to Sony FE 35mm F1.8'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. Sony FE 35mm F1.8 weighs 280g, which means it is 81g (22%) lighter than the Zeiss Batis 40mm F2 CF which has a weight of 361g.
Both Sony FE 35mm F1.8 and Zeiss Batis 40mm F2 CF has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony FX30, Sony A7 IV and Sony ZV-E10.
Sony FE 35mm F1.8 is a prime lens with fixed focal lenght of 35mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 52.5mm.
Zeiss Batis 40mm F2 CF is a prime lens with fixed focal lenght of 40mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 60mm.