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Matching lenses from each maker's lineup, plus some classic medium and large format lenses. Email me if something is wrong or missing.
Interactive 3D portrait ray-traced through the published US20160070086A1 optical prescription (10 elements in 7 groups, 1 aspherical) with a 20.0 mm entrance pupil and 0.7 m minimum focus.
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Matching lenses from each maker's lineup, plus some classic medium and large format lenses. Email me if something is wrong or missing.
| Optical & Portrait Metric | Measured / Patent Value | What It Means in Practice |
|---|---|---|
| Patent Prescription | US20160070086A1 · 10 elements in 7 groups (1 aspherical) | Traced surface by surface in WebGL2 |
| Entrance Pupil Diameter | 20.0 mm (at f/1.4) | Controls distant background blur disc size |
| Upper-Body Working Distance | 1.15 m | Camera-to-subject distance for head-to-waist framing |
| Effective Focal Length (Breathing) | 28.1 mm (+0.2%) | Actual framing focal length at portrait distance |
| Depth of Field (Sharp Zone) | 21 cm (1.05 m – 1.26 m) | Sharp zone at wide-open aperture |
| Minimum Focus Distance | 0.7 m | Closest focusing distance from the sensor |
Wide open at f/1.4, the Leica Summilux-M 28mm f/1.4 ASPH. has a 20.0 mm entrance pupil (28 mm ÷ 1.4). In an upper-body portrait at 1.15 m, the sharp depth-of-field zone spans 21 cm (1.05 m to 1.26 m), while mechanical vignetting and 10 glass elements shape the out-of-focus highlights.
Based on patent US20160070086A1, tracing the focusing group at 1.15 m gives an effective framing focal length of 28.1 mm (+0.2% vs. the nominal 28 mm). You can toggle "Match subject size" in the simulator to see the framing shift live.
The patent prescription (US20160070086A1) specifies 10 lens elements in 7 groups with 1 aspherical surfaces. The interactive Optical X-Ray above traces rays through every surface in real time.
Also see: depth of field, bokeh, crop factor, lens compression.