Sydney Observatory 2018 Sky guide cover

 

Above: the cover of the 2018 Sydney Observatory sky guide

H-alpha solar image taken with

Coronado 90mm h-alpha filter, Astro-Physics AP130GTX

PGR GX6.0mp camera

Processed with Avistack and Photoshop

 

Image Copyright Peter J Ward 2017

Can you see all 26 grey scales above?