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Jupiter seen as rainbow coloured ball


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How big is it in the eyepiece? Wondering if you're slightly out of focus. The Travelscope will naturally have some colour fringing (chromatic abberation) and this will be made worse if you're out of focus.

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Hello and welcome to SGL. Your telescope is a short tube refractor that will experience chromatic aberrations (colour fringing on bright objects). This is probably why your see a rainbow around Jupiter. Atmospheric refraction can also cause this problem but I suspect the problems you are experiencing are the result of the limitations of your telescope.

 

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I agree with Peter above, most likely over magnified and the limitations of the scope have been realised. Try observing the lunar surface with low magnification and let us know your results.

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2 minutes ago, Markos Symeonides said:

Is there a way to fix it?

It is probably not broken ..... but its limits have been reached. The images you see on the boxes are not a realistic representation of what you can see.

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3 minutes ago, Markos Symeonides said:

I see the lunar surface fine, with lots of detail, with every eyepiece (20mm,10mm,4mm)

That kind of confirms it then Markos... the scope has reached its limits with Jupiter :happy8:

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It depends on how you look at it, considering the distances involved the fact we can see anything at all is pretty amazing. Use the telescope for its strengths rather than it limitations. The Lunar surface is very interesting and you should see nicely coloured stars.

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Hi Marios. It is not that t is a bad telescope as such. Every telescope has its limitations and you have reached yours, especially if you are using the 4 mm eyepiece.with the 10 mm eyepiece you can view many targets.

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3 minutes ago, Markos Symeonides said:

Next time i get a telescope what would you recommend for a budget of about 300-400 euros?

Markos before you spend your cash have a read of this thread... it is very enlightening :happy8:

 

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Not necessarily a BAD telescope --- Just a £70 telescope?
(Assumed Celestron Travelscope 70). Sadly, "superlative"
view come at greater cost... Mostly. And even then? lol. :p

Welcome to the real world of Astronomy... "It isn't going
to look like they said in the adverts"? But I hope this will
be an incentive to understand... and encourage a certain
amount of persistence - And stubbornness we needed! :evil4:

Jupiter is not the ideal target for this (many) scope(s).
But Planets are not the only target around...
The Pleiades are still on view etc. etc. :)

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I have (although I don't use it anymore) a 70mm Travelscope. The scope is a good little starter scope, and you can get some decent views from it, although at higher magnifications you will see quite a bit of CA with it, especially on brighter objects like Venus and Jupiter. You will also notice this on the edge of the moon too if you look carefully. The maximum magnification your scope can deliver is around 140x magnification, so with a focul length of 400mm the 4mm EP gives a magnification of 100x, which should be OK with the scope still, but as the EP's supplied with the scope are not the best quality then you lose out on image also due to this along with CA in the view too. You could invest in a better 4mm EP that might improve the view at high end magnification, along with a semi-APO filter to attach to your EP to reduce the CA in the views too. 

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It's a decent, very portable, wide field, low power telescope which is what it was designed for. My guess is that most 70mm F/5.7 achromat refractors of this cost range would perform pretty much in the same way.

There are measures that you can take to improve the high power views a little but it's not going to be a strong bright object / high power performer whatever you do to it so I would not invest much money in trying to turn it into something that it is not.

What it can do, which many larger and more expensive scopes cannot, is be taken very easily and simply to very dark skies where it will show very nice low power views of the better known deep sky objects :icon_biggrin:

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Don't bin the scope just yet. I use one of these as a finder scope on my Dob and thought that it performs pretty well for the money. The  eyepieces that come with it are truely terrible. Pop in a better Plossl (simple low cost eyepiece design) and the view is much better! You will still struggle on the brightest objects. But, there are many clusters to explore...

Paul

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Always take your telescope outdoors for, in your case about 30-minutes will do - awhile to let it come to the ambient-temperature outside. Assuming you store it inside when not in use. Heat-patterns can cause optical-abberations, or contribute to them, and produce a distorted view.

Also be aware that if the target (Jupiter in this case) is low in the sky. Then it will be coming through a greater amount of our atmosphere, which can also contribute to this phenomena.

The already mentioned issues of too much magnification & poor 'seeing' as well. But do try again!

Have fun out there!

Dave

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When I look at Jupiter through my 76mm f=1250 f/16.5 achro I see a very small circle with a line across the northern hemisphere and a line across the southern hemisphere, no more detail (the moons are pinprick sharp). This is at 100x with a 12.5mm plossl.  If i use my xcel LX 7mm for 178x, I see a larger, blurrier, dimmer Jupiter with the same detail. F16 protects me from chromatic aberration unlike your fast scope but not sure that huge magnification with a small aperture is the way to go. 100x should be OK through a 3" refractor but Jupiter won't be huge at 100x, certainly not a centimetre across. A 4mm eyepiece is tricky to see through. My scope was originally fitted with a 0.965" 4mm ortho and I could barely see anything through it!

 

 

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47 minutes ago, Macavity said:

Not necessarily a BAD telescope --- Just a £70 telescope?
(Assumed Celestron Travelscope 70). Sadly, "superlative"
view come at greater cost... Mostly. And even then? lol. :p

Welcome to the real world of Astronomy... "It isn't going
to look like they said in the adverts"? But I hope this will
be an incentive to understand... and encourage a certain
amount of persistence - And stubbornness we needed! :evil4:

Jupiter is not the ideal target for this (many) scope(s).
But Planets are not the only target around...
The Pleiades are still on view etc. etc. :)

Don't knock £70 telescopes! My 76mm f/16.4 classic refractor cost £27!  My 130p reflector with eq2 and tripod cost £45. :-)

 

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2 minutes ago, newbie alert said:

I had a 76 and couldnt see anything on jupiter ..no details at all

Digital davem that might be the spider vanes you can see north and south..

I think Dave's F/16.5 is a refractor.

Sometimes you can see spikes through bright object if there is something like a powerline or telephone cable crossing near the line of sight. It does not actually need to be right through it, just near to it and you get a diffraction spike from it. I've discovered this the hard way by having a few such lines crossing my garden !

Also a 45 degree / 90 degree erecting prism type diagonal can cause a spike through bright objects. I think the Celestron 70 comes with such a diagonal as standard, which might not be helping things, astronomically speaking.

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