mini-OR from Bonny Doon

John Pierce

I used the excellent pair of cheap chinese 8x40 binocs that I picked up at the recent SJAA swapmeet to find Holmes (quite clear, barely visible naked eye), also Tuttle (not so visible naked eye, but clearly a comet in the binocs), and Andromeda (also clearly visible naked eye... it was quite dark overhead and all to the west, in spite of the 15% crescent moon).

I spent some time on the Trapezium in Orion, and by 7:30 or 8pm, it was high enough that I was clearly able to resolve #5, but i never did quite make out #6... I was using a older Celestron Ultima 12.5mm in a 2X Ultima shorty barlow (both from when they were still made in Japan), on my 10" f/4.5 Coulter Odyssey Compact that I recently refurbished. Last time I tried this, I was plagued with the huge diffraction spike created by the Coulter's original 'cross bar' secondary 'spider'. With the 1800destiny curved vane spider, there's no spikes at all, and stars make nice perfect pinpoints.

At one point, I wanted a wide field for something, so I stuck my 35mm Orion Ultrascopic in... Noted a very odd distortion, where bright stars would go from -- to | as I shifted in and out of focus, but never resolve to a point. Yet, the same eyepiece on my barlow gave excellent images. Anyone have any idea what might cause this? Is f/4.5 just too fast for this eyepiece? My colimation was decent but not great... It was good enough for 180 power on the moon to look nice and crisp, as well as nicely resolving trapezium #5 at both 180X (said 12.5+barlow) and 120X (an Orion Epic ED 9.5)