Project Optional. Used for the PDF report header.
Screen
Seats
Add a row for each row of seats, up to ten. Leave a row's distance blank to drop it from the drawing. Eye height auto-fills from the seat type; override per row if needed.
| Row | Distance from screen (mm) | Seat type | Eye height (mm) | Remove |
|---|
Targets
Results
Screen and band
Per-row outcomes
How to read this Background on the inputs, drawings, and per-row outcomes.
The two modes
This calculator answers either of two questions, depending on what you fill in. Mode A finds the ideal screen width for the seating distance you give. Mode B finds the ideal seating distance for the screen you give. The sightline geometry — top view, side view, riser heights — is produced in both modes.
Sightlines and risers
The side view draws each row's eye position plus the head of the row in front, then traces the sightline that needs to clear that head and still reach the bottom of the screen. Where it doesn't clear, the row needs to be raised — the riser height column shows how much. Recliner seats sit the viewer lower and a little further forward; both factors are reflected in the per-row numbers.
Guideline sources
Our own recommended practice: the best seat sees the picture 40–50° wide, and never less than 36°. The back row sees at least 30°. No seat sees more than 60°. THX advises at least 36° from the furthest seat. SMPTE EG 18 gave 30°; it was withdrawn in 2003.
Height: the top of the picture should be no more than 20° above the eye, and never more than 30°. The picture centre should be 0–10° above the eye, and never more than 15° above or below it. At the best seat, the eye sits between a third and half of the way up the picture.