The following sun images have been taken through an achromatic refractor Vixen Super-Polaris-80M. As a standard sun filter, the refractor has been equiped by an Astrosolar foil of
density 5. An infrared filter B+W 486 has been added for eye safety.
· Sun image taken on October 21, 2012, @ 13:03 UTC. Canon EOS 7D, exposure 1/2500s, ISO 400. Left: Original colors with blue domination due to the Astrosolar filter (Aluminum thin layer). Right: Black and white with increased contrast showing the limb darkening due to the atmosphere of the sun.
· Sun images taken on October 21, 2012, @ 12:50 UTC (with some clouds) and @ 13:04 UTC (sun disc free of clouds). The simple setup is shown on the three last pictures with young astronomers.
© Michel Willemin