As we’d expect given the new optics, the EF 24mm f/2.8 IS USM was able to outperform the EF 24mm f/2.8 despite its similar specifications. The Sharpness score for the new lens places it among lenses with the top score of 17 perceptual megapixels (P-MPix) when mounted on a full-frame Canon EOS 5D Mark II. The older EF 24mm f/2.8 scores acceptably at 14P-MPix, but the the newer optics make a noticable difference in resolution.
The new lens also shines when it comes to light transmission, with a Transmission Score that’s spot-on for an f/2.8 lens with a 2.8TStop. The EF 24mm f/2.8 on the other hand tested low for transmission coming in with a 3.3TStop, indicating that it loses a half stop.
Both lenses perform well on the Distortion metric, indicating that distortion is well controlled for such a short focal length. They also perform similarly on the Vignetting metric, both scoring -2EV, with lens shading strong at full aperture f/2.8 and still noticable between f/4 to f/22—not surprising for lenses at this focal length and aperture.
Slight chromatic aberration is noticable using both lenses, which scored similarly at 12µm and 13µm respectively for the new IS USM lens and the original lens.