Dark Window
Your deep sky companionYour deep sky imaging companion
Learn
Plain-language guides to the parts of astrophotography that trip people up, each with diagrams and a FAQ.
- Filters
Every kind of astro filter, what it passes and what to try.
- Calibration frames
Darks, flats, bias: how many, with what settings.
- Focusing
Bahtinov masks and getting sharp stars.
- Histogram guide
Reading the histogram to set exposure.
- Meridian flip
Why and when a German equatorial mount flips.
- Light pollution
Bortle scale, sources of skyglow, dark sites and satellite trails.
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