Nikon Nikkor-S Auto 50mm f/1.4 — Bokeh & Optical Ray-Tracing Simulator

Interactive 3D portrait ray-traced through the published US3560079A optical prescription (7 elements in 5 groups) with a 35.7 mm entrance pupil and 0.6 m minimum focus.

Loading scene…
0%

Optical & Portrait Specifications (Upper Body Framing)

Optical & Portrait Metric Measured / Patent Value What It Means in Practice
Patent Prescription US3560079A · 7 elements in 5 groups Traced surface by surface in WebGL2
Entrance Pupil Diameter 35.7 mm (at f/1.4) Controls distant background blur disc size
Corner Bokeh Roundness (90% Field) 70% at f/1.4 (≥86% from f/2) · -0.8 EV Mechanical vignetting (cat’s-eye vs. round corner highlights)
Background Field of View (Compression) 40° horizontal Width of the background room visible behind the subject
Upper-Body Working Distance 2.01 m Camera-to-subject distance for head-to-waist framing
Effective Focal Length (Breathing) 49.9 mm (-0.1%) Actual framing focal length at portrait distance
Depth of Field (Sharp Zone) 20 cm (1.92 m – 2.12 m) Sharp zone at wide-open aperture
Minimum Focus Distance 0.6 m Closest focusing distance from the sensor

Questions

How much background blur and corner cat's-eye does the Nikon Nikkor-S Auto 50mm f/1.4 produce?

Wide open at f/1.4, the Nikon Nikkor-S Auto 50mm f/1.4 has a 35.7 mm entrance pupil (50 mm ÷ 1.4) and 70% bokeh roundness in the 90% corner (-0.8 EV corner falloff, reaching ≥86% roundness from f/2). In an upper-body portrait at 2.01 m, the sharp depth-of-field zone spans 20 cm (1.92 m to 2.12 m) with a 40° horizontal background angle of view.

Does the Nikon Nikkor-S Auto 50mm f/1.4 show focus breathing at portrait distance?

Based on patent US3560079A, tracing the focusing group at 2.01 m gives an effective framing focal length of 49.9 mm (-0.1% vs. the nominal 50 mm). You can toggle "Match subject size" in the simulator to see the framing shift live.

What optical design is inside the Nikon Nikkor-S Auto 50mm f/1.4?

The patent prescription (US3560079A) specifies 7 lens elements in 5 groups. The interactive Optical X-Ray above traces rays through every surface in real time.

Related comparisons

Compare with similar portrait lenses

All lens comparisons

Also see: depth of field, bokeh, crop factor, lens compression.