Image scale tells you how much sky each pixel covers. It decides whether stars look sharp, how big targets appear and whether you're over- or under-sampling the seeing.
Enter pixel pitch, focal length and sensor size.
How it works
Scale = 206.265 × pixel (µm) ÷ focal (mm) arcsec/px.
FAQ
What's ideal sampling?
Roughly 2–3 pixels across the seeing FWHM.
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