The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 15mm f1.4 DC C and the Sigma 18-50mm F2.8 DC DN C 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 18-50mm F2.8 DC DN C is the longer of the two lenses at 75mm. The Sigma 15mm f1.4 DC C with a length of 65mm, is 10mm shorter. Besides being longer, the Sigma 18-50mm F2.8 DC DN C also has a larger diameter of 65mm compared to the Sigma 15mm f1.4 DC C's 64mm 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 15mm f1.4 DC C weighs 225g, which means it is 65g (22%) lighter than the Sigma 18-50mm F2.8 DC DN C which has a weight of 290g.
Filter Threads
The Sigma 15mm f1.4 DC C has a filter size of 58mm whereas the Sigma 18-50mm F2.8 DC DN C has a 55mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Sigma 15mm f1.4 DC C:
And these are the 55mm filters that we recommend for the Sigma 18-50mm F2.8 DC DN C:
Lens Mounts
The Sigma 15mm f1.4 DC C has the Fujifilm X lens mount whereas the Sigma 18-50mm F2.8 DC DN C has the Sony E lens mount. Some of the latest released cameras that are compatible with these mounts are Fujifilm X-T30 III, Fujifilm X-E5 and Fujifilm X-M5 for the Fujifilm X Mount and Sony ZV-E10 II, Sony A6700 and Sony FX30 for the Sony E Mount.
Sigma 15mm f1.4 DC C is also available in the Canon RF and Sony E mounts.
Sigma 18-50mm F2.8 DC DN C is also available in Leica L and Fujifilm X mounts.
Focal Range
Sigma 15mm f1.4 DC C is a prime lens with fixed focal lenght of 15mm which has an effective (full-frame 35mm equivalent) focal range of
22.5mm when used on a APS-C / DX format camera.
On the other hand, the Sigma 18-50mm F2.8 DC DN C has a focal range of 18-50mm and 2.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 27-75mm when used on a APS-C / DX format camera.
