Sharp and bright, but strong vignetting at widest apertures
Considering its relatively low price, the EF 40mm f/2.8 STM was a solid performer on our DxOMark Camera Lens Ratings. When mounted on a Canon EOS 5D Mark II, it rates among the top seven standard prime lenses (with a focal range between 35mm and 85mm) achieving an overall DxOMark Score of 26.
Strengths of the Canon EF 40mm f/2.8 STM include resolution, as evidenced by its Sharpness score of 15P-Mpix. Additionally, our sharpness measurements and field maps (below) indicated that the lens delivered relatively consistent edge-to-edge sharpness from f/2.8 to f/11.
Canon EF 40mm f/2.8 STM: Acutance in the field
Other strengths include its low geometric distortion and well-controlled chromatic aberration as indicated by its low Chromatic Aberration score of 10µm.
The one weakness of the Canon EF 40mm f/2.8 STM was the strong vignetting evident at the widest apertures. You can see from the vignetting field maps below that at f/2.8, there is heavy shading across 2/3 of the field.
Canon EF 40mm f/2.8 STM: Shading in the field
Further readings for the Canon EF 40mm f/2.8 STM review
To provide photographers with a broader perspective about mobiles, lenses and cameras, here are links to articles, reviews, and analyses of photographic equipment produced by DxOMark, renown websites, magazines or blogs.
June 12, 2013
Our review of the Canon EF 40mm f/2.8 STM lens. In the latest of our lens reviews brought to you in partnership with DxOMark, we take a look at Canon's slimline 'pancake' prime for its APS-C and full frame SLRs. It's one of the smallest and cheapest lenses currently on the market, and includes a stepper motor for silent focusing during movie recording. But does its small size and low price result in compromised optics? Read our review to find out.
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