The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony FE 20mm F1.8 G and the Zeiss Milvus 18mm F2.8 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. Zeiss Milvus 18mm F2.8 is the longer of the two lenses at 93mm. The Sony FE 20mm F1.8 G with a length of 85mm, is 8mm shorter. On the other hand, the Sony FE 20mm F1.8 G has a larger diameter of 74mm compared to the Zeiss Milvus 18mm F2.8's 73mm 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. Sony FE 20mm F1.8 G weighs 373g, which means it is 348g (48%) lighter than the Zeiss Milvus 18mm F2.8 which has a weight of 721g.
Filter Threads
The Sony FE 20mm F1.8 G has a filter size of 67mm whereas the Zeiss Milvus 18mm F2.8 has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Sony FE 20mm F1.8 G:
And these are the 77mm filters that we recommend for the Zeiss Milvus 18mm F2.8:
Lens Mounts
The Sony FE 20mm F1.8 G has the Sony E lens mount whereas the Zeiss Milvus 18mm F2.8 has the Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with these mounts are Sony A9 III, Sony A7C Mark II and Sony A7CR for the Sony E Mount and Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount.
Zeiss Milvus 18mm F2.8 is also available in Canon EF mount.
Focal Range
Sony FE 20mm F1.8 G is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
30mm.
On the other hand, the Zeiss Milvus 18mm F2.8 is a prime lens with fixed focal lenght of 18mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 27mm.