Trouble With Telescope

[ahutch927]

Hi all I am new comer here and to amateur astronomy in general and I need some help! I currently own an Orion Observer 70mm refractor with a 10mm eyepiece. I can't seem to get it to work as intended. When I look through it the magnification is very poor. I am not sure if I am doing something wrong or if I simply have low magnification. It is advertised as providing 70x magnification but it hardly seems this powerful. Can anyone clear this up for me? I am sorry if this is a dumb question but I am new to this, and I was expecting to be able to see things like Saturn's rings etc. I can hardly see all of Jupiter's moons through it!

[northcanadian]

Perhaps a 25mm or 32mm would help?

Cheers

[cantab]

Planets do have a small apparent size, so even magnified they're still not exactly big or in-your-face, but detail should be visible on Jupiter at 70x, I've seen the main bands at half that.

[RMcCallum]

Your specs, tell me if I'm wrong.

Aperture 70mm

Focal Length 700mm

Focal ratio f/10.0

You have a low focal ratio, in turn a slow scope. This will be quite forgiving on eyepieces, which is good if you are using the given EPs, are you using the stock EPs?

The magnifcation you get with this EP is x70 (700/10 = 70) so not very high, your hightest useful magnification will be around x140, but I wouldn't try it as atmospheric conditions rarely allow such things from scopes. So your about half way in magnification, which shouldn't cause problems.

Another thing to think about is collimation, is your scope collimated? I recommend reading AstroBabys guide for more help.

As for Jupiters bands and Saturns Rings, I think what your lacking in is aperture (don't quote me I'm no expert), you will need a slightly larger scope eg. 114mm or more. I can see them clear as a bell in my 130mm at x36.

[RMcCallum]

A bigger aperture = more light = brighter, clearer image.

[michael.h.f.wilkinson]

I suspect the scope is a 70mm F/10 refractor, so collimation should not be an issue. If the EP has H10 on it, it is a Huygens (the sound you hear is Christiaan Huygens turning in his grave) EP and these are generally poor quality plastic thingies. This could show considerable chromatic and other errors. If it says K10 or MA10, it is a Kelner or Modified Achromat (very similar three-lens design). These are better, and should be able to show a reasonable image. Two darker bands on Jupiter should be visible, as well as the moon. If the EP is a 10mm Plossl it should be OK, and we must look at other problems. One could be the diagonal. Some of these scopes are supplied with a 45 deg correct image diagonal (Amici prism is the correct term). These vary quite a bit in quality.

Finally, a very clear night like we had yesterday (in Groningen) can still be a night of bad seeing. This means that the air is full of turbulence, due to warm air (it was sunny yesterday) rising from the ground as the temperatures drop. If Jupiter is seen over the roofs of houses things get worse. If bright stars twinkle a lot, that is a sign of turbulence.

[ronin]

70x will enable Jupiter to be seen reasonably, couple of bands and up tp 4 moons if they are not hidden.

It will not really be enough to see Saturn's rings.

As said a Huygens eyepiece is not great and you should consider a plossl or three. Assuming as someone said f/10 so a 700mm FL you are probably looking at a 6mm eyepiece for Saturn = 116x. Could try a 7mm for the 100x ? A 8mm would deliver 87x. I would suggest against a 6mm as it is pushing everything a bit.

Ignoring whatever is written on the box I would not expect the scope to go beyond 100-110x in realistic terms.

On that basis and if you bought a few more eyepieces then a 7mm plossl, a 10mm and a 25mm.

Astronomy can be expensive.

[michael.h.f.wilkinson]

I spotted Saturn's rings with a 70mm F/10 at school, and they were easy at 40x, and much better with a 9mm Symmetric EP (similar to Plossl).

[Steep]

The gist of what everyone is saying here seems to be buy yourself a better eyepiece. A good quality eyepiece can be had for less thsn £50 (look for the BST ones from eBay seller Skys the Limit) and will be easy to sell on if you decide to move on. From what the other guys are telling you I'd try a 10mm first, maybe go as high as 8mm? for a bit more magnification if you want to but also consider a wider one as well for views of larger objects.

[ahutch927]

Thanks everyone for the responses. I am not sure what kind of eyepiece it is that came with the scope but it is most likely of low quality. Even so, I am not sure what to expect seeing through it at 70x magnification. Jupiter still looks like a pinpoint of light, albeit a slightly larger one, but I can hardly even make out the moons. Is this normal for 70x magnification? Poor quality eyepiece or not I still thought I would be able to see color on the planets. This is a link to the scope I have:

http://www.telescope.com/Orion-Observer-70mm-Equatorial-Refractor-Telescope/p/9882.uts?keyword=orion%20observer

[JamesF]

I'd have a look at the Moon with it first I think. It should be easy to find and judge the quality of the image. If what you see appears to be a very poor quality image then I think it's worth looking at better eyepieces.

James

[RichieP]

At 70x Jupiter should be very obviously a sphere rather than a point of light, and you should be able to see a band or two.

[LukeSkywatcher]

I have easily seen Saturn and its rings in a 90mm refractor with a focal length of 1000mm (F11) with a 10mm Kellner EP. Your scope is very similar to my 90mm refractor.

Your specs, tell me if I'm wrong.

Aperture 70mm

Focal Length 700mm

Focal ratio f/10.0

If correct, i think the scope is just below par for observing planets, but it should be just enough...............so i think the problem lies elsewhere.

[ahutch927]

So I am not sure what I am doing wrong then. Perhaps I have the eyepiece seated incorrectly or I put the scope together wrong. I am hoping it is not a mechanical issue that needs to be fixed, it has been doing this out of box.

[LukeSkywatcher]

With any scope, the useful magnification stated in the specs can automatically be halved realistically. So if your scope says 70x...............you can forget that and work on 35X (depending on where in the world you live). If you live in a location where the skies are the deepest darkest................then 70x is possible.

You are in or near Philly. Thats a pretty big urban area. How far from the city are you.

Personally i think with a 70mm scope in or near such a BIG city as Philly, you are fighing against the light pollution from the city. Maybe a light pollution filter would be worth investing in.

Ultimately though, i think you need a bit more aperture. 90mm is a start, but the bigger the better. 130-150-200mm would be my suggestion.

[ahutch927]

I am about 15 miles from the city so light pollution could be affecting it. I will look into a bigger aperture as well, thanks again for all the help.

[LukeSkywatcher]

I am about 15 miles from the city so light pollution could be affecting it. I will look into a bigger aperture as well, thanks again for all the help.

Before investing in a larger apeture scope, try a light pollution filter.

[cantab]

Thanks everyone for the responses. I am not sure what kind of eyepiece it is that came with the scope but it is most likely of low quality. Even so, I am not sure what to expect seeing through it at 70x magnification. Jupiter still looks like a pinpoint of light, albeit a slightly larger one, but I can hardly even make out the moons. Is this normal for 70x magnification? Poor quality eyepiece or not I still thought I would be able to see color on the planets. This is a link to the scope I have:

http://www.telescope...=orion observer

You're not missing the target are you? Jupiter should be obviously non-stellar and its moons will look like stars but should be obvious, though colours will be muted or absent. Do you have the 25mm eyepiece the scope was sold with? If so, use that to home in on targets to start with.

Certainly it sounds like something is wrong, your descriptions aren't in accord with my expectations of that scope.

[michael.h.f.wilkinson]

I suspect you are seeing Aldebaran, rather than Jupiter. They are quite close in the sky, but Jupiter should definitely not be a pinpoint of light at 70x. I can spot it as a disk in my 15x70 binoculars.

[ahutch927]

I could potentially be aiming wrong, but I don't think it is likely because the Moon also does not appear as large as I would expect it to be at 70x magnification.

[Lee M]

A couple of thoughts (bearing in mind I'm a mere beginner myself):

Have a look at a distant terrestrial object in daylight - *nowhere near the direction of the sun*. See if you can get that sharp. You can then fiddle about with the kit in the daylight & you'll know whether you should be seeing a tree or building or flag pole.

If the view's no good - do you have any other local astronomers, a club etc where someone could lend you an eyepiece to check whether it's the eyepiece or the main tube?

HTH

Lee