Thursday, August 9, 2018

Sky Magic


Under the dark skies of Vermont I finally got to test a trick that Chirag told me about.  It is how to make the stars that make up constellations more visible.  He was using this technique when we were at Big Bend National Park.  But the skies need to be dark to make it work, and the skies in my back yard certainly are not dark.  But they sure are here in Vermont.  The trick is to use a mild diffusion filter during either all or part of an exposure of the sky.  So here are two exposures.  This one, above has the diffusion filter in place for the whole exposure.  Perhaps I need to try it with only half the exposure.  The constellation is Cygnus the swan, and it appears as a kite or Christian cross on its side.  You can clearly see the main stars of Cygnus in the photo above.   Notice also that the color differences of the stars are so obvious.  Did you know that there are differences in color among the stars?  There are red ones and blue ones, and variations in between.  Below is the photograph without the filter, and for the life of me, I cannot find Cygnus.  So the trick works, but I need to experiment to get perhaps a bit more subtlety.  But so far, I am thrilled with the results.


1 comment:

Anonymous said...

So much information I did not know, like the colors of stars. Great photo. Thank you.
Joan