The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 50mm f1.4 USM and the Canon EF 50mm f/1.8 STM 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. Canon 50mm f1.4 USM is the longer of the two lenses at 51mm. The Canon EF 50mm f/1.8 STM with a length of 39mm, is 12mm shorter. Besides being longer, the Canon 50mm f1.4 USM also has a larger diameter of 74mm compared to the Canon EF 50mm f/1.8 STM's 69mm 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. Canon EF 50mm f/1.8 STM weighs 159g, 45% (131g) lighter than the Canon 50mm f1.4 USM's weight of 290g.
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 50mm f1.4 USM has a filter size of 58mm whereas the Canon EF 50mm f/1.8 STM has a 49mm 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 Canon 50mm f1.4 USM:
And these are the 49mm filters that we recommend for the Canon EF 50mm f/1.8 STM:
Lens Mounts
Both the Canon 50mm f1.4 USM and the Canon EF 50mm f/1.8 STM 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.
Focal Range
Both lenses have the same focal range of
50mm but while Canon 50mm f1.4 USM has the fastest aperture of
F1.4, the Canon EF 50mm f/1.8 STM's widest aperture value is
F1.8.