Dew might seem harmless, but it can seriously degrade your astrophotography. When moisture condenses on lenses or mirrors, it creates a thin water layer that scatters light, resulting in blurry images with reduced contrast and muted colors.
This foggy effect is especially problematic during long exposures, where clarity and detail are critical. You might notice milky patches or loss of focus that can’t be fixed in post-processing.
To keep your images crisp, it’s essential to understand how dew forms and take steps to prevent it before it ruins your session.