Arcturus

I had a couple hours to waste before a nebula came up over the trees, so I took a few exposures of the nearby star Arcturus. I had my Baader UHC filter on, which mostly lets some red wavelengths through as well as a band in the cyan wavelengths. The photo really shows how light reflects internally in the filter, witnessed by the concentric rings around the star. I just really like diffraction spikes.