Portrait At-a-Glance Comparison (Upper Body Framing)
| Optical & Portrait Metric | Canon EF 50mm f/1.8 II | Canon RF 50mm F1.8 STM | What It Means in Practice |
|---|---|---|---|
| Upper-Body Working Distance | 2.01 m | 2.01 m | Identical working distance—both frame an upper-body portrait from the exact same spot. |
| Background Field of View (Compression) | 39° | 39° | Identical 39° horizontal background view behind the subject. |
| Entrance Pupil Diameter | 27.8 mm (f/1.8) | 27.8 mm (f/1.8) | Nearly identical distant background blur size at equal framing. |
| Corner Bokeh Roundness (90% Field) | 75% (-0.6 EV) | 77% (-0.5 EV) | Similar corner bokeh shape wide open (75% vs. 77% roundness at 90% field). |
| Effective Focal Length (Breathing) | 50.7 mm (+1.4%) | 51.4 mm (+2.8%) | At 2.0 m, Canon EF 50mm f/1.8 II frames like a 50.7 mm lens while Canon RF 50mm F1.8 STM frames like a 51.4 mm lens. |
| Depth of Field (Sharp Zone) | 26 cm (1.89 m – 2.15 m) | 26 cm (1.89 m – 2.15 m) | Both lenses deliver the exact same 26 cm sharp focus zone. |
| Minimum Focus Distance | 0.45 m | 0.3 m | Canon RF 50mm F1.8 STM focuses 15 cm closer (0.45 m vs. 0.3 m) for tighter close-ups. |