The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 40mm f2.8 STM and the Sigma 40mm F1.4 DG HSM A 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 40mm F1.4 DG HSM A is the longer of the two lenses at 131mm. The Canon 40mm f2.8 STM with a length of 22mm, is 109mm shorter. Besides being longer, the Sigma 40mm F1.4 DG HSM A also has a larger diameter of 88mm compared to the Canon 40mm f2.8 STM's 68mm 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.
Below you can find the dimension and weight table of the Standard Prime Lenses in Canon EF Mount for size comparison purposes.
Standard Lenses in Canon EF Mount for Size Comparison
Filter Threads
The Canon 40mm f2.8 STM has a filter size of 52mm whereas the Sigma 40mm F1.4 DG HSM A 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 52mm filters that we recommend you to consider for the Canon 40mm f2.8 STM:
And these are the 82mm filters that we recommend for the Sigma 40mm F1.4 DG HSM A:
Lens Mounts
Both the Canon 40mm f2.8 STM and the Sigma 40mm 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.
Sigma 40mm F1.4 DG HSM A is also available in Nikon F (FX) , Sigma SA, Sony E and Leica L mounts.
Focal Range
Both lenses have the same focal range of
40mm but while Canon 40mm f2.8 STM has the fastest aperture of
F2.8, the Sigma 40mm F1.4 DG HSM A's widest aperture value is
F1.4.