The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 40mm F1.4 DG HSM A and the Sigma 30mm F1.4 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 40mm F1.4 DG HSM A is the longer of the two lenses at 131mm. The Sigma 30mm F1.4 DC HSM with a length of 63mm, is 68mm shorter. Besides being longer, the Sigma 40mm F1.4 DG HSM A also has a larger diameter of 88mm compared to the Sigma 30mm F1.4 DC HSM's 74mm 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 Sigma 40mm F1.4 DG HSM A has a filter size of 82mm whereas the Sigma 30mm F1.4 DC HSM has a 62mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 82mm filters that we recommend you to consider for the Sigma 40mm F1.4 DG HSM A:
And these are the 62mm filters that we recommend for the Sigma 30mm F1.4 DC HSM:
Lens Mounts
Both the Sigma 40mm F1.4 DG HSM A and the Sigma 30mm F1.4 DC HSM 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.
Sigma 30mm F1.4 DC HSM is also available in Nikon F (DX) and Sigma SA mounts.
Focal Range
Sigma 40mm F1.4 DG HSM A is a prime lens with fixed focal lenght of 40mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
64mm.
On the other hand, the Sigma 30mm F1.4 DC HSM is a prime lens with fixed focal lenght of 30mm which has an effective (full-frame 35mm equivalent) focal range of 48mm when used on a APS-C / DX format camera.