Secondary ghosting images on Jupiter

[Nobby2]

Is the most likely cause of lack of sharp edges on jupiter a collimation issue? I am getting a second or third image floating above or to one side of the planet. Clusters aren't as bad although there is possibly a lack of clarity.

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[jambouk]

Can you post a copy of the image for us to see?

What scope and camera are you using?

What stacking software?

JD

[Nobby2]

Explain some more thanks. This is not a digital imaging issue, its just a basic looking through the scope. I recently purchased a precision brand equatorial mount. 203mm aperture, 800 mm focal length scope. Being a No name brand it was always going to be a risk but worth a try for the price i payed. I have collimated a smaller 114mm skywatcher previously but just cant nail this one. I am considering purchasing a laser collimator tomorrow. Does this sound like a good idea?

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[Nobby2]

I should have said it was a reflector

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[jambouk]

Ah, this is when looking down the telescope. In that respect I don't have a clue, sorry.

Hopefully someone else will be along who understands collimation issues in refelctors.... Sounds complicated.

Good luck.

Jd

[Langy]

I'm sure someone in the know will give some good advice.

Have you tried a star test to see if it is out that way?

[Nobby2]

Yes the star test is not good. I even had a dark edge obscuring part of the out of focus star. Indicating secondary mirror is out of alignment.

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[Joseki]

A combination Cheshire tool is pretty useful and not particularly expensive - but you've already collimated a 114mm scope, so perhaps you already have something? 

http://www.garyseronik.com/?q=node/165

If you've got a reflector you will need to deal with collimation, so if your scope is out you have to sort it out anyway and it's quite probably going to affect the views in the way you describe (it would be the first thing I tried, followed by attempting to reduce sources of internal reflection - assuming of course you're not inside a house looking through the glass of the window).  The dimensions of the scope are a little worrying especially for a no-name/unbranded scope - focal length 800mm & mirror size 200mm is f/4 which is quite a demanding setup (both on the mirror quality and how easy it is to collimate it). 

I have a baader laser collimator which is very nice as well as the combination Cheshire tool, but I think how useful the laser collimator is depends on how much lateral wobble/movement there is (etc) in your focuser, and you still need something (e.g. a collimation cap) to help align the secondary since the laser is only useful in adjusting the primary once the secondary is sorted (or at least that's how I've been using it ).

[Nobby2]

Thanks

Much appreciated. Will keep people informed on my progress

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[oldpink]

I have a baader laser collimator which is very nice as well as the combination Cheshire tool, but I think how useful the laser collimator is depends on how much lateral wobble/movement there is (etc) in your focuser, and you still need something (e.g. a collimation cap) to help align the secondary since the laser is only useful in adjusting the primary once the secondary is sorted (or at least that's how I've been using it ).

I used my laser collimator to do both primary & secondry mirrors and sorted it out a treat

[Nobby2]

I visited my retail store bintell .com.au the binocular and tellescope shop Sydney. My advise was the secondary images of jupiter most likely to be the quality of my eye piece. Purchased a new 20mm eyepiece (yet to test, but confident).

The collimation by a laser collimator did the trick. The primary alignment was so far out initially that it only produced a glow and line instead of a dot. After a phone call all was fixed. The key was sticking a centre donut sticker on the primary after drawing up a template.

Will test on the next fine night

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[Nobby2]

Very cloudy tonight but the star test on a gloomy Sirius gave a good even circular pattern.

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[Nobby2]

Tested in good local conditions. The collimation is good and i am probably getting the best out the scope as you can get. There is still a level of ghosting secondary images on jupiter however star clusters and general detail on smaller light sources (clusters) have improved. I am afraid however that the quality of the primary is not great. This looks like a product of a Chinese company called GSO Guan Sheng Optics gs-telescope.com. The primary mirror is probably not parabolic although difficult to confirm.

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[Charic]

Well you seem to have sorted most things out. Does it look like this?  http://www.gs-telescope.com/content.asp?id=79