Comfort zones

A comfort zone is the parallax range a viewer can fuse without fatigue. The literature defines it by different criteria; some are expressed in percent, some in angle, some in diopters.

The comfort window of a screen

Percentage budgets do not know the screen size; the same percentage means many more millimeters on a large screen. This is why the calculator and the mastering page take each screen's window as the narrowest of three limits:

• Screen-type budget: cinema +1% / −2%, home and personal screens +2% / −1%.
• Divergence: back parallax cannot exceed the ratio interocular distance / screen width.
• Angular parallax: at most 1° in front and behind.

Examples

• TV 55", 2.5 m: window −1% … +2%; both limits are set by the budget.
• Cinema, 10 m screen, 15 m: window −2% … +0.65%; the back limit is set by divergence (65 mm / 10 m).
• Large auditorium, 16 m screen, 16 m: window −1.75% … +0.41%; the front limit is set by 1°, the back limit by divergence.

Whether the same shot fits different screens, and how many masters it needs, is calculated on the Mastering page.

Limits in the literature

Limits cited in the literature, with their sources: