Portrait At-a-Glance Comparison (Upper Body Framing)
| Optical & Portrait Metric | Canon RF 135mm F1.8 L IS USM | Sony FE 135mm F1.8 GM | What It Means in Practice |
|---|---|---|---|
| Upper-Body Working Distance | 5.40 m | 5.40 m | Identical working distance—both frame an upper-body portrait from the exact same spot. |
| Background Field of View (Compression) | 15° | 16° | Identical 15° horizontal background view behind the subject. |
| Entrance Pupil Diameter | 75.0 mm (f/1.8) | 75.0 mm (f/1.8) | Nearly identical distant background blur size at equal framing. |
| Corner Bokeh Roundness (90% Field) | 62% (-0.6 EV) | 61% (-0.9 EV) | Similar corner bokeh shape wide open (62% vs. 61% roundness at 90% field). |
| Effective Focal Length (Breathing) | 132.7 mm (-1.7%) | 130.8 mm (-3.1%) | At 5.4 m, Canon RF 135mm F1.8 L IS USM frames like a 132.7 mm lens while Sony FE 135mm F1.8 GM frames like a 130.8 mm lens. |
| Depth of Field (Sharp Zone) | 25 cm (5.28 m – 5.53 m) | 25 cm (5.28 m – 5.53 m) | Both lenses deliver the exact same 25 cm sharp focus zone. |
| Minimum Focus Distance | 0.7 m | 0.7 m | Both lenses share the same 0.7 m close-focus limit. |