The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Venus 105mm F2 and the Sigma 18-35mm F1.8 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. Sigma 18-35mm F1.8 DC HSM is the longer of the two lenses at 121mm. The Venus 105mm F2 with a length of 99mm, is 22mm shorter. Besides being longer, the Sigma 18-35mm F1.8 DC HSM also has a larger diameter of 78mm compared to the Venus 105mm F2's 76mm diameter.
Below you can find a scaled side-by-side image of Venus 105mm F2 and Sigma 18-35mm F1.8 DC HSM to get a better idea of how their sizes compare in real life.
Comparison image of the Venus 105mm F2 and the Sigma 18-35mm F1.8 DC HSM Size and Weight 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. Venus 105mm F2 weighs 745g, which means it is 65g (8%) lighter than the Sigma 18-35mm F1.8 DC HSM which has a weight of 810g.
Filter Threads
The Venus 105mm F2 has a filter size of 67mm whereas the Sigma 18-35mm F1.8 DC HSM has a 72mm 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 Venus 105mm F2:
And these are the 72mm filters that we recommend for the Sigma 18-35mm F1.8 DC HSM:
Lens Mounts
The Venus 105mm F2 has the Pentax KAF2 lens mount whereas the Sigma 18-35mm F1.8 DC HSM has the Sigma SA lens mount . Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Mono , Pentax KF and Pentax K-3 III for the Pentax KAF2 Mount and Sigma SD1 Merrill , Sigma SD1 and
Sony E , Canon EF , Nikon F (FX) and Sony Alpha mounts.
Canon EF , Pentax KAF , Sony Alpha and Nikon F (DX) mounts.
Focal Range
Venus 105mm F2 is a prime lens with fixed focal lenght of 105mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
157.5mm .
On the other hand, the Sigma 18-35mm F1.8 DC HSM has a focal range of 18-35mm and 1.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-52.5mm when used on a APS-C / DX format camera.
