The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Zeiss Milvus 18mm F2.8 and the Sigma 10-20mm F3.5 EX DC HSM 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 Sigma 10-20mm F3.5 EX DC HSM with a length of 88mm, is 5mm shorter. On the other hand, the Sigma 10-20mm F3.5 EX DC HSM has a larger diameter of 87mm 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. Sigma 10-20mm F3.5 EX DC HSM weighs 520g, 27% (201g) lighter than the Zeiss Milvus 18mm F2.8's weight of 721g.
Filter Threads
The Zeiss Milvus 18mm F2.8 has a filter size of 77mm whereas the Sigma 10-20mm F3.5 EX DC HSM has a 82mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 77mm filters that we recommend you to consider for the Zeiss Milvus 18mm F2.8:
And these are the 82mm filters that we recommend for the Sigma 10-20mm F3.5 EX DC HSM:
Lens Mounts
Both the Zeiss Milvus 18mm F2.8 and the Sigma 10-20mm F3.5 EX DC HSM has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Blackmagic URSA 12K LF, Z CAM E2-F6 II 6K and Z CAM E2-S6 II 6K.
Zeiss Milvus 18mm F2.8 is also available in the Nikon F (FX) mount.
Sigma 10-20mm F3.5 EX DC HSM is also available in Pentax KAF3 , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
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 1.6x crop, it provides a 35mm (FF) equivalent of
28.8mm.
On the other hand, the Sigma 10-20mm F3.5 EX DC HSM has a focal range of 10-20mm and 2.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 16-32mm when used on a APS-C / DX format camera.
