Posted by Robin Vann at 02:56 on 2010 Aug 11
I suspect my assertion that I could see Ganymede and Callisto as tiny discs was not correct. They do look like tiny discs at 280x but I am thinking now that this is an optical issue or lack of experience; seeing 1 arcsecond objects as discs seems pretty unlikely at this magnification.I have now dropped the magnification to 150x where I feel the contrast is better; I am still using the Neodymium + IR cut, as this seems to ‘bring up’ the reddish details. I shall now detail the reddish areas I am identifying. Obviously they are seperated by the appropriate zones.I am seeing the NEB strongly and, somewhat less strongly, the SPR, which seems to occupy more latitude than it should: I think I’m seeing the SPR and one or more of the STB as a whole, without seeing anything of an STZ.There is also a glimpse of the NTB showing during moments of best seeing and very occasionally, a hint of the NNTB.Telescope: Skywatcher 150mm f/8Eyepiece: Baader Hyperion 8mmFilter: Baader Neodymium + IR Cut (Moon and Skyglow): obviously there is no moon troubling me, but the filter seems to be enhancing the reddish areas I’m discussing.I still can’t wait for my Orion (UK) SPX200 f/6 to arrive.Robin VannWarwickshire