Exit Pupil Calculator
Exit pupil = objective lens diameter ÷ magnification. Larger exit pupils gather more light — useful for dawn and dusk deer stalking. The human eye dilates to ~7 mm in darkness; an exit pupil above that wastes light without benefit.
Exit Pupil
4.17 mm
Good — suitable for low-light field use
Quick presets
Exit Pupil Reference Guide
| Exit Pupil | Suitability |
|---|---|
| > 7 mm | Exceeds eye limit — wasted light but no penalty |
| 5–7 mm | Excellent — full light capture in low light |
| 4–5 mm | Good — suitable for dawn/dusk stalking |
| 3–4 mm | Daylight and bright twilight only |
| < 3 mm | Daylight only — not suitable for low-light field use |
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