Filling in as the premium normal-length lens, the EF-M 32mm f/1.4 STM from Canon is a 51.2mm-equivalent prime characterized by its impressively bright f/1.4 maximum aperture. This fast design affords increased control over depth of field for working with selective focus techniques, and also suits shooting in difficult lighting conditions. One aspherical element is used in the optical design, and helps to reduce spherical aberrations and distortion for improved sharpness and clarity throughout the aperture range. A Super Spectra Coating has also been applied to control flare and ghosting for greater contrast when shooting in bright or backlit conditions. Additionally, an STM motor is featured and provides quick, smooth, and precise autofocus performance along with full-time manual focus override.
Sometimes, it is easy to justify the purchase of a lens for a subset of its attributes (such as price), but when it is time to select the ideal lens for a particular use, the focal length always becomes a very important attribute. The focal length determines the angle of view which determines the subject distance required for the desired framing and the distance from the subject determines the perspective.
The 32mm focal length is a rather unusual one in the DSLR and MILC (Mirrorless Interchangeable Lens Camera) market, though brands like Cooke and Arri offer a variety of ultra-expensive 32mm models for the filmmaking world. On an EOS M camera with an APS-C-format imaging sensor, this lens provides an angle of view similar to a 51.2mm lens on a full frame camera, hitting very close to the ultra-popular 50mm focal length angle of view.
What is the APS-C 32mm focal length useful for? This angle of view appears very natural, approximating how we perceive a scene with our own eyes in field of view and perspective terms and affords very strong general-purpose usefulness. As you will likely figure out, I didn't find a lack of subjects for this lens. They're everywhere.
The 32mm APS-C focal length works especially well for still and video capture of fashion, portraiture, weddings, documentaries, the street, lifestyle, sports, architecture, landscape, and around-the-home activities along with general studio photography applications including product photography. As you likely noted, a number of good applications for this lens include people as subjects.
Still, this lens did not fly under everyone's radar and many have said, in one form or another, "You have to try this lens!" That opportunity finally came and ... the advice was spot-on.
This tiny, lightweight little lens has a great general-purpose focal length, an ultra-wide aperture, impressive image quality (including at f/1.4) and a very reasonable price. This lens is reason alone to buy an EOS M-series camera just to use it on.