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Sum0
2002-Dec-29, 12:17 PM
I've had a Bushnell 115mm (4.5 inch) reflector scope with a f/ratio of 4.5 for about a month now. And for some reason, I can't see planets at all well.
I tried looking at Jupiter last night with my 20mm, 12mm and 4mm eyepieces, and all I got was a bright fuzzy blob, and I couldn't see any moons. With Saturn I can barely glimpse what might be the ring, but I can't see any more with a smaller eyepiece. Nebulae and star clusters look pretty good though.
So what do you think is the problem? Is it simply because the f/ratio is too short for viewing planets, or a defect with the scope?

Starshark
2002-Dec-29, 12:20 PM
Can I ask, are you near the ocean? Are you near a city or similar? Have you accounted for pollution or air moisture? I live near the ocean myself, and this is the sort of thing that happens when I try to use a telescope around here.

Starshark
2002-Dec-29, 12:21 PM
Whoops, forget I said anything. I can't really see star clusters here, either. Have to go 100 km inland.

Either that or my Mom's telescope is crap.

Sum0
2002-Dec-29, 12:34 PM
If it does help in any way, i'm about 29km (18 miles) from the sea and i'm on the outskirts of a small city, with Orion's Sword easily visible with averted vision. Pretty vague, I know, but...

John Kierein
2002-Dec-29, 01:12 PM
try here and links
http://www.space.com/spacewatch/telescope_tips_021227.html

GrapesOfWrath
2002-Dec-29, 03:59 PM
On 2002-12-29 07:34, Sum0 wrote:
If it does help in any way, i'm about 29km (18 miles) from the sea and i'm on the outskirts of a small city, with Orion's Sword easily visible with averted vision. Pretty vague, I know, but...

You have to avert your vision to see Orion's sword? Aren't the star combinations mag. four? That's pretty bright.

Anyway, have you collimated your telescope? That would help.

Sum0
2002-Dec-29, 10:08 PM
I thought about that, although I've kind of left it as a last resort because i'm afraid of messing the whole thing up. But I suppose it's the best option, so i'll give it a go.

GrapesOfWrath
2002-Dec-30, 12:36 AM
www.bushnell.com/support/manuals/telescopes/Voyager%252078-2010.pdf+Bushnell+collimation&hl=en&start=9&ie=UTF-8]Here (http://216.239.51.100/search?q=cache:XdgbILlwhSEC:[url) is a webpage[/url] that discusses collimation of the Bushnell 4.5in telescopes--but you probably already have some instructions, right? HTH

Sum0
2002-Dec-30, 11:23 AM
Thanks for the link - hopefully everything should go well now...

traztx
2002-Dec-30, 03:52 PM
I had the same problem back when I thought windex could be used on eyepieces. It messes them up.

To fix the blur, I carefully disassembled the eyepieces and used a lens pen to clean them.

Now the planets look beautiful.

JackC
2002-Dec-30, 07:23 PM
As the others have said, start with a thorough cleaning and collimation - it isn't as hard as it looks. I have done it and was pretty worried at first - now I just sit down and do it without thinking - and yes, my scope is really junk, so I have to do it often. It has not been set right yet!

Be aware that moving a scope from a warm house to a cold outside area to observe will often cloud things up - that can really mess up your vision! Best to take the scope out, let it sit for a bit.

Jack