Performance Review of the Canon EF 50mm f/1.2L USM Lens
Comparison with EF 50mm f/1.4 USM Lens

The Canon EF 50mm f/1.2L USM lens was evaluated and was compared to the EF 50mm f/1.4 with respect to resolution, 50% MTF and bokeh performance. The primary question I wanted to answer was: Would the 1.2L outperform the f/1.4 USM lens at f/1.4 and f/2. The short answer is: Yes.

Canon EF 50mm f/1.2L USM Lens Canon EF 50mm f/1.4 USM Lens and EF 50mm f/1.2L USM Lens

Resolution and 50% MTF Performance Data
Link to Methods Used The graphs show the best value obtained with 2 to 5 replicates.

Both lenses are very sharp in the center of the field. 50% MTF (Center weighted).
The 1.2L lens outperforms the 1.4 lens at f/1.4 and f/2.
At f/2.8 and f/4, the f/1.4 lens outperforms the L-lens.


Click on the photo to compare diffuse blurring of backgrounds and out of focus light pattern at various apertures with the EF 50mm f/1.2L and EF 50mm f/1.4 lenses. Click on the various images to see full width images cropped from portrait orientation photographs.
  • Out of Focus blurring is slightly better with the f/1.2L lens at f/1.4 and f/2
  • Out of focus light patterns of the aperture diaphragm are more rounded with the f/1.2L lens

Image Sharpness with a Mannequin Target

Detail of eyes showing image sharpness. The f/1.2L lens produces slightly sharper images at f/1.4 and f/2 than the f/1.4 lens.

Improved Resistance to Flare

Canon EF 50mm f/1.2L USM Lens Canon EF 50mm f/1.4 USM Lens
Monolight flash exposes the mannequin at f/2. Snooted monolight flash in background exposes the back of the mannequin at f/5.6. The new 1.2L lens shows markedly improved resistance to flare and internal reflections.


Compare vignetting as aperture is closed.
Both lenses vignette moderately at f/1.4 and very mildly at f/2. Illumination is almost even at f/2.8, and even at f/4

Corner Sharpness and Chromatic Aberration (CA)

Lens f/1.2 f/1.4 f/2 f/2.8 f/4
EF 50mm f/1.2L Soft
Moderate CA
Moderate CA
Moderate CA
Mild CA
Mild CA
EF 50mm f/1.4 Soft
Moderate CA
Moderate CA
Very Sharp
Mild CA
Very Sharp

Autofocus Accuracy and Speed

Focus accuracy and consistency was tested by focusing on a distant wall pattern and then refocusing on the mannequin eye and firing the shutter of an EOS-1Ds Mark II. In 20 repeat focusing actions, each lens was slightly out of focus 3 of 20 times (15%). Autofocus speed of each lens seemed to be comparable.

The autofocus test was conducted with good lighting. Tests run under low ambient lighting might reveal differences in autofocus speed and accuracy between the two lenses.

In Focus 17 of 20 repeat tests for each lens (85%). Out of focus 3 of 20 repeat tests for each lens (15%).

Worried about reports of this lens backfocusing?

Linear Distortion

Both lenses have very mild barrel distortion.

Lens Data

EF 50mm f/1.2L USM EF 50mm f/1.4 USM
Lens elements/groups 8/6 7/6
Blade number in aperture diaphragm 8 8
Max diameter x length 85.4mm x 65.5mm 73.8mm x 50.5mm
Filter Size 72mm 58mm
Weight 545 g 290 g
Motor USM Micro USM
Price, $ USD $1599

Summary / Conclusions

EF 50mm f/1.2L USM
The superbly built EF 50mm f/1.2L lens provided modestly sharper images with better out of focus blurring (bokeh) at f/1.4 and f/2 and was much more resistant to flare and internal reflections than the EF 50mm f/1.4 lens. This improved performance comes at the cost of increased size, weight and a greater than 5-fold higher purchase price. The f/1.2L lens did not focus faster or more accurately than the f/1.4 lens in these tests run under good lighting. Corner sharpness was lower and corner chromatic aberration was greater with the f/1.2L lens.

EF 50mm f/1.4 USM
This lens is well built, compact and focuses fast. Optical performance (resolution, microcontrast and bokeh) is superb. It is a tremendous value lens that offers high performance at low cost.

Equipment Review Index

Review of EF 50mm f/1.0L


© 2006, William L. Castleman
Initially posted 17 December 2006, Revised 23 January 2007