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View Full Version here: : Halo effect around Jupiter


Pinwheel
11-10-2010, 08:55 AM
Hi all, I dragged out the 8" last night for a look at the Moon & Jupiter, excellent night however regardless of which EP I used Jupiter when focused perfectly had a large halo/smuggy haze over it. To the naked eye the stars & Jupiter looked clear & sharp but though the scope this odd effect not unlike looking though a greasy EP, Anyone else see this or do I have a problem? :sadeyes:

mental4astro
11-10-2010, 09:24 AM
This tells me that there was dew condensing either on your primary mirror, secondary mirror or both, and maybe even your eyepieces, especially the eye lens (the eyepiece lens closest to you eye) from your breath.

If its your mirrors, a hair dryer will help remove it. It will help with your EPs too. Another thing to keep your EPs warm is a hot water bottle placed with your EPs. Even keeping your EPs in your jacket pockets is an old trick too.

These a measures to help you out of immediate pickle. There are other more expensive measures, and more permanent measures too.

Pinwheel
11-10-2010, 09:32 AM
Hi Alex

I think I found the problem, The secondary mirror had a waxy smear completely over it. I just finished cleaning it & it looks crystal clear now. Will test it out again tonight to see if I'm right. I'm thinking it was caused by the plastic cover plate as certain plastics give off fumes. The telescope had not been out for several months in it's closed state.

mswhin63
11-10-2010, 11:50 AM
On really dewy night even with the naked eye you get a halo around the moon and Jupiter maybe that was an affect too.