Jupiter

[O2B3]

I am i looking at Jupiter the image has 2 lines across it?

But every time I try to zoom in the image gets bigger but looks like a doughnut I've been using a skyliner 200p with an 1.25" 10m lens also I am having trouble finding the milkyway where should i be looking in in the sky I live in the south of England. Not sure if I am doing this right :-) hope someone out there can give me some pointers

[malc-c]

Can't help much regarding the issue with Jupiter, but the milky way runs up from the south between Orion and Gemini, overhead, through cassiopea down through cygnus - but you will need dark skies to see it.  Can't make it out tonight from my location in town as the sky seem quite bright, but on occasions it's more noticeable

[Avocette]

A Skyliner 200p has a focus knob but no 'zoom' control. You are doing quite well to see the two stripes on Jupiter (and presumably the four moons in a line to one or both sides of it?) but when you turn the focusser it will get bigger and blurry and will eventually look like a white donut with a black centre but it's then well out of focus!

[houston]

You will need a zoom eyepiece to zoom in on objects.

[O2B3]

Thanks for your reply so if I get a bigger lens would I see Jupiter bigger and better :-)

[Peter Drew]

As Avocette says, you do not zoom with the focuser to get a larger image, you have to change the eyepiece. The smaller the number on the eyepiece the higher the magnification. Apart from needing as dark a sky as possible, the position of the Milky Way changes during the year, it is best seen when overhead during late Summer. 

[Laurie61]

Thanks for your reply so if I get a bigger lens would I see Jupiter bigger and better :-)

Hi, yes you need a shorter focal length lens to get higher power, a 6 mm in your f 6 200 mm will give you 200 X 

[malc-c]

Ahh he's not using a zoom eyepiece.

O2B3 - as others have said, when you change eyepieces you need to re-focus.  To get higher magnifications you use shorter focal length eyepieces - divide the focal length of the eyepiece into the focal length of the telscope to get the magnification.  But, as you increase magnification you also decrease brighness and contrast, so thngs seem less defined

[LukeSkywatcher]

Jupiter in a 200mm scope with a 10mm eyepiece should be fine. Typically it has 4 bands across the surface visible. Two of them are very strong and visible while the other two may be a tad soft and harder to see, depending on conditions and your focus. The fact that you see Jupiter as a donut means you have not hit the "sweet spot" and you are a bit out on either side of sharp focus. 

[Avocette]

But beware! The condition of the sky (even when it's clear) is often the limiting factor due to lack of 'transparency' and poor 'seeing' caused by wind and turbulence. With your 10mm eyepiece you've got a magnification of 1200/10 = 120x. It is tempting to step up to 200x like Laurie61 suggests with a 6mm, but often when you do so you don't see any better because clarity of view suffers. With your scope you have a nice wide aperture to capture plenty of light and you will be able to search for Deep Sky Objects (DSOs) like the Orion Nebula. For them you will be often using your 25mm (48x) to give you a wider view and a 32mm Plossl (37.5x) is often recommended as a first purchase after you've got used to the scope and the standard eyepieces that came with it.

[Charic]

02B3.......Hi, A lower number on the eyepiece increases the magnification, and as the magnification goes up and you get nearer to Jupiter, it gets bigger, but only to an extent, because the limits of the telescopes aperture, focal length and eyepiece in use and seeing conditions, all affect the final image.  

If your using the supplied 10mm EP, you can improve on its quality somewhat, by getting another lens. I chose an 8mm BST Starguider  and its brilliant. Much cleaner and  wider images. That said Jupiter is still very small! I can also use the 5mm BST with a 1.5 barlow lens (just the lens, no barlow tube) and I can see Jupiter even better, but its still quite small in the FOV (field of View). The other night I witnessed Io's (Eye Oh!) transit across the face of the planet, and could clearly see the shadow of the Moon as a perfect black circle. The best seeing conditions I've yet witnessed.

If you want to get  bigger images from your telescope a bigger aperture may be the answer, say 10" plus. But then at 10" you'd want more and so on.

The doughnut your explaining just sounds like your outside of the focus for the lens in use. Once the EP(eyepiece) is focused, thats it really, unless you change EP or install a Zoom-Lens". There is no other way to zoom in.  Looking at the doughnut when you zoom in or out on the focuser wheel, If you de-focus slightly, you see what is known as an Airey Disk. This when viewed correctly should show concentric rings of black and white (grey & white). If the rings are concentric, it tells you that the mirrors in the telescope are correctly aligned and working well. If the rings are elongated to one side, then collimation is required. This aligns the mirrors.

[ecw199]

I'm near to you have the same scope. I was out viewing Jupiter tonight with the 10mm eyepiece and was able to see some great detail including a bit in the lower band that looked like a great white spot! I think one of the key things to do is to keep looking. The longer you look the more you see. I spent a good 40mins tonight looking at Jupiter and the more I looked the more detail I could make out and the more in focus it seemed to be. 

[John]

I think it can be confusing for someone relatively new to using a scope because a star or planet appears to get larger as you move the focuser away from the point of sharpest focus.

But it is actually when the star or planet looks the smallest through the eyepiece, that it is actually in focus. 

As you go further away from that point of sharp focus, the planet or star disk appears to expand and then, with a scope with a secondary mirror, you start to see the dark shadow of the secondary mirror in the center of the unfocused disk.

I think this is the "zoom" (moving the focuser) and "doughnut" effect that O2B3 is referring to.

When Jupiter looks it's smallest size, it is in focus and you should see at least two and maybe more bands across it's disk. These are it's cloud bands.

A 6mm eyepiece will indeed give you a larger in focus view of Jupiter with your scope.

The Milky Way is best seen without a telescope and I find it easier to see it in the late Spring / Summer running though the constellations of Cygnus through to Cassiopeia as a misty band across the sky.

[HeadInTheStars]

I only have a 3" reflector and I can see detail of Jupiter excelent. However I can't see shadow transits though. Keep at it and you will train your eye to see better in the lense. You could also try averted vision where you place jupiter or other objects off to the side of your field of view and look at it indirectly in the eye piece it will sometimes give you a better image.