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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 US8508864B2 optical prescription (14 elements in 11 groups, 2 aspherical) with a 60.0 mm entrance pupil and 1 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 | US8508864B2 · 14 elements in 11 groups (2 aspherical) | Traced surface by surface in WebGL2 |
| Entrance Pupil Diameter | 60.0 mm (at f/1.5) | Controls distant background blur disc size |
| Upper-Body Working Distance | 3.61 m | Camera-to-subject distance for head-to-waist framing |
| Effective Focal Length (Breathing) | 91.5 mm (+1.7%) | Actual framing focal length at portrait distance |
| Depth of Field (Sharp Zone) | 21 cm (3.50 m – 3.72 m) | Sharp zone at wide-open aperture |
| Minimum Focus Distance | 1 m | Closest focusing distance from the sensor |
Wide open at f/1.5, the Leica Summilux-M 90mm f/1.5 ASPH. has a 60.0 mm entrance pupil (90 mm ÷ 1.5). In an upper-body portrait at 3.61 m, the sharp depth-of-field zone spans 21 cm (3.50 m to 3.72 m), while mechanical vignetting and 14 glass elements shape the out-of-focus highlights.
Based on patent US8508864B2, tracing the focusing group at 3.61 m gives an effective framing focal length of 91.5 mm (+1.7% vs. the nominal 90 mm). You can toggle "Match subject size" in the simulator to see the framing shift live.
The patent prescription (US8508864B2) specifies 14 lens elements in 11 groups with 2 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.