Sunday 9 June 2013

AR11765 White Light 8th June

ar11765 wl by Mark Townley
ar11765 wl, a photo by Mark Townley on Flickr.

I used the 127mm refractor to get this closeup shot of AR11765 at a focal length of 3500mm using the DMK31. Using the Lunt solar wedge without any additional neutral density filtration, when used with a UV/IR cut and a Baader solar continuum filter I was able to use an exposure time of 1/5000th second to freeze the seeing. I'm pleased with this shot as it is just beginning to show the polygonal shape of the granulation cells caused as a result of convection on the sun. The long focal length was achieved by stacking barlows, however the extra glass does have a subtle effect of reducing some contrast and this approach can be plagued with dust bunnies if not careful. However, all this aside i'm pleased with what is one of my best whitelight shots for a while.