|Canon EF 50mm f/1.8 STM|
The Canon EF 50mm f/1.8 II is something of a joke in the photographic world... a light-hearted positive joke but a joke nonetheless. The punchline is that it's a remarkably sharp lens with toy-like build quality that comes at absurdly low retail price. It's the closest thing in the camera world to a piece of fast-fashion clothing; you never get the sense that they intended fro you to keep it forever. Many people who bought this lens did so with a smile on their face because of how little they were paying. It's a lens that was in dire need of upgrading... and in a way it wasn't. While it is true that you need to continuously improve in order to maintain brand loyalty, there is something to be said about offering ridiculously low prices.
The Canon EF 50mm f/1.8 STM is a fitting step up from the older f/1.8, and in every conceivable way, improves upon the previous lens. It's still cheap, just not as jokingly cheap as the the last time. So has Canon maintained the magic "so cheap it's good" formula or has something changed during the upgrade?
Design and Build Quality
The STM lens is a very much a modern lens build-wise; the f/1.8 II was a film-era hold over. This new lens feels tighter and does not have any barrel wobble. The lens mount has also changed from plastic to metal. The focus ring is more substantial than before, and like all STM lenses, its a fly-by-wire affair.
The big improvement is the change to STM stepper motors. The autofocus mechanism no longer sounds like the gear-train of a toy car, and is in keeping with the almost silent operation of the other STM lenses, like the 18-55mm kit lens for the T5i, T6i or T6s. The keyword is "almost"... the copy that I had access to had a slight whisper to it that other STM lenses don't. For most people this won't matter, but the idea with the STM lenses as opposed to the USM lenses is that the former focus quietly when used for video. The problem is that being "nearly silent" is not particularly useful, as you need to be absolutely silent in order to create any kind of quality video.
Except for the change in number of aperture blades, the optical design is exactly the same as the previous two versions on the Canon 50mm f/1.8. For the price, this is understandable, as the extra cost clearly goes into the packaging and new focus motors. A change in optical design would have bumped the price up a bit more, probably closer to where the Nikon AF-S 50mm f/1.8 G sits. The minimum aperture is now f/22 instead of f/16, which allows for a bit more exposure leeway in extremely bright situations. The change from 5 straight blades to 7 rounded ones makes the bokeh a bit more pleasing, but otherwise the image quality is unchanged. It's a lens that you can use wide-open, but it does better stopped down. Like almost all 50mm DSLR lenses, peak sharpness is roughly around f/5.6, and truth be told it's not that different from the more expensive EF 50mm f/1.4 USM.
Though Canon get frequent criticism from the photographic community for fairly non-exciting consumer DSLR bodies, their consumer-level lens set has quietly developed into one of the best value-oriented propositions in modern digital photography. The EF-S 10-18mm STM and the EF-S 28mm f2.8 STM are both extremely cheap and useful for what they do. The EF 50mm STM makes for a natural protrait lens on the crop bodies, more so than the 40mm f/2.8 which is too short for serious portrait work.
All told, this was an update that was long over due, as the antiquated build of the version II lens did not fit in with the rest of the Canon lineup. While it's a bit of a letdown that the image quality hasn't been changed, truth be told, that wasn't the weak point of the old lens. The 50mm STM is therefore, still a "no-brainer" purchase, it's just not as ridiculous a no-brainer as before.
With thanks to Broadway Camera