Ring-necked Ducks! - 25-26 Mar 2017
I spent some digiscoping them from the cover of the spruce trees overlooking the west side of the pond. I also swapped out eyepieces on my Zeiss 85T*Fl Diascope; the 40X W returned and the 25-75X Zoom Eyepiece got benched. The reason? These Ring-necks showed me just how bad the chromatic aberration is on the 25-75X. Their brilliant white bills next to their dark-purple heads and bright yellow eyes really show the yellow-blue CA bands that appear when the optics are just not up to par. The 40X W eyepiece has significantly-improved sharpness and only a trace CA under similar-lighting conditions.
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