Dew forms on your lens when its surface cools below the dew point — a common problem for astrophotography and sunrise shoots. Enter temperature and relative humidity to see the dew point and the risk level.
How it works
Magnus formula: γ = ln(RH/100) + aT/(b+T); T_d = bγ ÷ (a − γ), with a = 17.62, b = 243.12 °C.
FAQ
How do I prevent dew?
A USB lens heater band, a lens hood and keeping the lens slightly warmer than the air.
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