I'm with you - I can occassionally pick it in a 25" in good conditions, not been able to in a 10", and not even in my magical Antares-splitting 4" Unitron.
What I can always see in any scope from 3"-25" is a ghost image of Sirius from one of the internal surfaces of the eyepiece, and at these powers I'm usually looking through a TV radian, so it's not like the eyepiece is especially bad. Unless people can confirm the correct separation and position angle of the pup, it's hard to be sure they haven't seen a ghost. Of course, my 41 year old eyes are a lot yellower than they were.
cheers,
Andrew.
Quote:
Originally Posted by The Mekon
I have been trying to resolve Sirius for the past few weeks. Last night here in Whyalla conditions were excellent. Seeing conditions were steady and transparency in the day was excellent, indicated by clear views across the Spencer Gulf to the Flinders Ranges. The full moon was just rising in the east and Sirius high in the north.
Using my Astro-Tech 106, at 144x I was still unable to make out any companion to Sirius. I had started observing in twilight and continued until full night. Shifting the scope to Adhara showed its companion easily. The 5th and 6th stars were visibile in the trapezium. Eta Orion was well split with dark sky between.
So I am with Skysurfer and his original post, unable to split Sirius. I find it impossible to believe observations reported on North American & European forums claiming detection of Sirius B at around 30 degrees elevation with 80mm scopes, when I seem to be getting nowhere with a bigger scope and better conditions.
For the record this scope shows Sirius with 2 diffraction rings, the second quite faint, Sirius B, by my estimate should be clear of these diffraction rings.
Perhaps my eyesight is losing its edge, I use to be a pretty good observer of doubles 20 years ago.
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