As I was admiring my recent image of Luna, I started thinking about the imaging scale and resolution. Using Stellarium, I found that the apparent diameter of Luna on the night I imaged it was 30′ 35.6″, or 1,835.6 arcseconds. The moon’s real diameter is 3,474.8 km, or 2,159.14 miles. The image scale on my deep-sky configuration is 0.6465 arcseconds per pixel. This suggests the moon’s image diameter would be 2840 pixels. Finally, the resolution is
\frac{2159.14 \texttt{mi}}{2840 \texttt{pix}} = 0.76 \frac{\texttt{mi}}{\texttt{pix}}or one pixel is about 3/4 of a mile!
If I were on the moon imaging Earth, my dead-end street would appear as about one pixel. I would easily be able to discern Akron, Cleveland, and larger lakes in the area. That’s an incredible resolution, especially for widefield! My planetary configuration suggests about 0.097 arcseconds per pixel, which would give a resolution of a little over 1/10 of a mile, or 600 feet, per pixel! That’s a bit past the theoretical resolution limitation, 0.38 arcseconds, of a 12″ telescope. But it’s fun to think about, anyways.
