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Leica DG Summilux 25mm f/1.4 II ASPH. — Bokeh & Optical Ray-Tracing Simulator
Interactive 3D portrait ray-traced through the published JP2013-003324A optical prescription (9 elements in 7 groups, 3 aspherical) with a 17.9 mm entrance pupil and 0.3 m minimum focus.
Optical & Portrait Specifications (Upper Body Framing)
| Optical & Portrait Metric | Measured / Patent Value | What It Means in Practice |
|---|---|---|
| Patent Prescription | JP2013-003324A · 9 elements in 7 groups (3 aspherical) | Traced surface by surface in WebGL2 |
| Entrance Pupil Diameter | 17.9 mm (at f/1.4) | Controls distant background blur disc size |
| Upper-Body Working Distance | 2.10 m | Camera-to-subject distance for head-to-waist framing |
| Effective Focal Length (Breathing) | 24.7 mm (-1.1%) | Actual framing focal length at portrait distance |
| Depth of Field (Sharp Zone) | 42 cm (1.90 m – 2.33 m) | Sharp zone at wide-open aperture |
| Minimum Focus Distance | 0.3 m | Closest focusing distance from the sensor |
Questions
How much background blur does the Leica DG Summilux 25mm f/1.4 II ASPH. produce?
Wide open at f/1.4, the Leica DG Summilux 25mm f/1.4 II ASPH. has a 17.9 mm entrance pupil (25 mm ÷ 1.4). In an upper-body portrait at 2.10 m, the sharp depth-of-field zone spans 42 cm (1.90 m to 2.33 m), while mechanical vignetting and 9 glass elements shape the out-of-focus highlights.
Does the Leica DG Summilux 25mm f/1.4 II ASPH. show focus breathing at portrait distance?
Based on patent JP2013-003324A, tracing the focusing group at 2.10 m gives an effective framing focal length of 24.7 mm (-1.1% vs. the nominal 25 mm). You can toggle "Match subject size" in the simulator to see the framing shift live.
What optical design is inside the Leica DG Summilux 25mm f/1.4 II ASPH.?
The patent prescription (JP2013-003324A) specifies 9 lens elements in 7 groups with 3 aspherical surfaces. The interactive Optical X-Ray above traces rays through every surface in real time.
Head-to-head patent comparisons with Leica DG Summilux 25mm f/1.4 II ASPH.
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Also see: depth of field, bokeh, crop factor, lens compression.