Another short window and this time the bull’s eye, and some hyads. Aldebaran is number 14 on the glitz list, with variable mag 0.75-0.95, 400 x luminosity, and 40 x larger than solar, although they share similar mass. At 65 LY from earth it appears to lie on the edge of the open hyades cluster. As a red giant, Aldebaran smoulders at 3700 degrees. Following the Pleiades, the bull, or bison in N American folklore is a portent of spring, and hopefully better skies for us all.
A simple capture with my Samyang lens wide open at f2, 30s exposures through an L-Pro filter are too long, washing out the star colour. A good focus was achieved with a Bahtinov mask. Interestingly apart from tweaking focus, no change was made to backspace, yet tilt is much worse in the bottom of this image. Hmm… some more 0.1mm shims arrived yesterday, so I’ll try adding another.
As pointed out by
@Dale Penkala in my last image, there is an obvious blue/brown gradient across the field. I’m putting this down to the bright moonlight, and a short lens hood. I tried GraXpert AI as an alternative to DBE in Siril (Rev B) - a slightly better background I think, but the gradient is still there. Any other thoughts welcome, as always. Thanks for looking.
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