This week we’re going to take a look at one of my favorite lenses, the Canon RF 50mm f/1.8 STM, also known as the Nifty Fifty.

The RF 50mm f/1.8 is more or less the same as the EF 50mm f/1.8 STM but updated with the new RF mount and some slight tweaks to the optics.

Why many photographers use a 50mm lens is that the focal length approximates the angle of view of human vision, and the f/1.8 aperture is fairly fast, allowing you to have nice bokeh in the background to make your subject stand out while being useful in low-light situations. This makes it a good lens for not much money.

I bought this lens just before going on a trip where the main purpose wasn’t photography, so I had to fit everything I needed (camera, strap, battery charger, etcetera) in a small camera bag. Mounted on the Canon RP, I was able to fit the body with the lens attached but the hood reversed in a jacket pocket. It served me well on the trip.

The RF 50mm f/1.8 has the same combination control and manual focus ring found on other smaller RF lenses, like the 16mm f/2.8 and the 24-105 STM. Since getting my R6 I have found a new love for the control ring, as it allows me to use it as an aperture ring, instead of controlling the aperture through a dial on the camera body. It has only one switch that changes between focus and control functions. Despite the small size, it is still easy to hold.

Image quality isn’t bad, especially for the price, though my R6’s mere 20 megapixels are more forgiving. The only bad part is the corners are a little soft and there is some chromatic aberration, especially with branches, but the latter can be cleaned up by applying a lens profile in post-processing.

Another change with the RF version of the Nifty Fifty is a slightly higher magnification ratio of 0.25x compared to the EF version’s 0.21x. The RF 50mm can focus as close as 30 centimeters from the sensor. This increase in magnification ratio is a characteristic of several inexpensive RF lenses, including the 24-105 STM and 16mm f/2.8, and is the result of being able to place larger lens elements closer to the sensor in a mirrorless camera.

The one disappointing thing about this lens is its focus motor. The STM motor is loud as it focuses. I was honestly shocked at how loud it is, as between STM and USM focus motor technologies, the STM motor is supposed to be the quieter one. It is also slow to focus, particularly going from one end of the focus range to the other, and it occasionally focuses on the wrong thing, even if the target is stationary. This is particularly the case when in servo AF with eye plus tracking mode. The R6 has a fantastic autofocus system that is let down by this lens. Manual focus override can help though. There is a “movie servo AF” mode that promises to make it quieter for videos, but I did not evaluate this feature.

I would recommend this lens for anyone with an R series camera because it’s nice to have something with a large aperture for a relatively low price, even if the autofocus motor is a bit noisy. The lens is quite small, just 70mm long, and weighs a mere 165 grams. It can be bought new for $180 or refurbished for $130.