27 minute star trails in a single exposure!

The image was a little bit noisy, but cleaned up nicely using Topaz De-Noise. There’s a few hotpixels and colour noise but you wouldn’t know unless you looked at the full-res shot.

Radio Telescope Star Trails

It was captured at ISO200, f/9 for 27 minutes, with a Canon 5DMk2 and 16-35 lens @ 16mm. I came up with those figures by using an ‘exposure equivalence’ calculator in Photo Pills. I took a short 30 second exposure to get the right ‘light’, and then worked back to see what ISO and f/# I needed if I wanted a 30 minute exposure to have the same ‘light’.

Pretty happy with how it turned out!

Thanks for looking!