Canon EF 50mm f/1.8 STM - Review / Test Report - Sample Images & Verdict
Lens Reviews - Canon EOS (Full Format)

Verdict

The Canon EF 50mm f/1.8 STM is a slight improvement over the old EF 50mm f/1.8 II - more so mechanically rather than optically. Now the old EF 50mm f/1.8 II was already a good lens actually especially when stopped down. The EF 50mm f/1.8 STM has a much higher center sharpness at fully open aperture though. The low contrast in the image borders/corners remains an issue but the resolution is quite decent here. Stopping down to f/2.8 helps to lift the overall quality but the lens really shines between f/4 and f/8 where it doesn't really get any better than that actually. The low CAs also contribute to the high sharpness perception at medium aperture settings. Just like its predecessor, it produces a hefty amount of vignetting at fully open aperture. Some photographers are actually after such an effect e.g. for portraits. However, otherwise you probably prefer to stop down a bit or correct the issue during post-processing. Image distortions aren't completely negligible but still very low. An unfortunate weakness of the lens remains the bokeh. There's also some bokeh fringing at large apertures but this is nothing out of the ordinary actually.

The build quality has been substantially improved. While it remains a light-weight lens, it doesn't feel like a toy anymore. Canon is using high quality plastics based on a metal mount and there's a decent focus ring now. Whether the new STM AF is an improvement or not may be debatable. While we haven't taken any formal measurements here, the AF doesn't seem to be any faster than on the EF 50mm f/1.8 II. However, the noise during focus operations has been reduced and full-time manual focusing is now also possible.

Thus the Canon EF 50mm f/1.8 STM is certainly a worthy successor of the EF 50mm f/1.8 II but they aren't worlds apart either.

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