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Help! Newbie here, apparently incapable of using a telescope! What am I doing wrong?


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So, my Skyliner 200P 8" Dobson arrived yesterday and, after setting it up, I went straight out to the garden to have a peek through it, as last night was forecast to be the only cloudless night of the week.  I stayed outside for 2 hours, desperately trying to see something fascinating through the 'scope, but sadly I was extremely disappointed.  Don't get me wrong, I'm completely aware that this will be due to my own ineptitude, and not the 'scope itself... so I'm here with a plea for HELP!!

Basically, the night sky looked far more astounding through my own eyes than through the telescope, which is why I realise I must've been doing something wrong.  As far as I'm aware, I set the telescope up properly as per the instructions... but perhaps I missed something?!  The instructions weren't the most detailed, so maybe I did do something wrong?

All I can see through the telescope is a bunch of very, very far away and tiny dots that are stars (shock horror...).  None of them were in focus, despite constantly turning the focusing knob in vain.  Sometimes they were blurry, sometimes there were about 10 of the same star; nothing I did would put it in focus!

Also, the view through the telescope looked exactly the same with both eyepieces (a 10mm and 25mm, which were supplied with the scope) and also without any eyepieces at all (so again, I must've done something wrong!!)

I was under the impression that I would be able to see the planets, and perhaps some detail on Jupiter (I don't have unrealistic expectations, but I thought I'd see far more than I did!)  Jupiter basically looked like a slightly brighter star through my telescope.  It had no definition or details, it was blurred like the stars around it, and there was no way of even being able to tell if it was a planet!  Do I need a higher magnification to see the planets, or should I be able to do that just with the equipment supplied with the scope?

Anyway, if anyone can figure out from that what I'm doing wrong then I will forever be in your debt :p  I thought I had read enough to figure out how to use a relatively simple telescope, but apparently I'm not as clever as I'd hoped!  There must've been some fundamental part of the setup that I missed somehow, or something!

(I haven't learnt all my telescope-y jargon yet, so if you could dumb things down for me it'd be appreciated haha!)

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Hello. With an 8" dob you should be able to make out more detail on Jupiter than you describe to be honest, cloud belts for example or even the Great Red Spot if it is in view. Stars will almost always look like dots as they are too far away although some will be different colours.

The weather in the UK at the moment is very wet and cold, did you check the mirror for any build up of dew as this can set in quite quickly and make everything look blurry....

James

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Hi Nadine, if you weren't able to focus there are a couple of possibilities.

Did you have both the 1.25" and 2" extensions in the focuser at the same time? This is a common mistake that will prevent the scope from focusing. If you are using the supplied eyepieces then you only need the 1.25" extension.

When you were turning the focus wheel, was the focuser moving in and out? If it wasn't, you need to undo the focus lock screw on the underside of the focuser.

Hope this helps.

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I think the first steps should be to set it up during the day, make sure you can get it focused on some distant landmark (the further away the better, probably) and get the finder aligned with the scope.  The Moon would then be a good target because it's quite hard to miss.  It might take a few days for the Moon to be visible again because we're very close to new Moon at the moment.

James

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Hi Nadine and welcome to SGL :) Stars always look like points of light in any telescope and most of the time we look at stars in groups like clusters (globular/open) or as double stars or interesting asterisms. The rest of the time folks are looking at galaxies, nebulae, planets, and other interesting objects (eg comets).

First thing to do is get the scope focused in daylight and confirm you are focusing correctly. Use a distant object over a mile away (church spire or pylon tip). Get the object central in the eyepiece and take the opportunity to line up the finder scope with the same view central on the cross hairs. Use the 25mm first then refine the accuracy by putting the 10mm in and repeat.

If the scope won't come to focus in daylight then check if the focus tube is actually moving when you turn the knobs. Ensure it's not locked by the screw on the underside of the focuser tube. Once you are sure you are focusing correctly and able to point properly using the finder you should be set to go at night. If you're still having a problem then come back for more help and we'll take it from there. :)

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Absolutely what James said. Set up in daylight and when you have successfully got something in focus, align your red dot finder (ask if you need help with this) and start out on the moon.

Good luck!!!

EDIT: Sorry, overlapped with brantuk's reply!!!

Edited by m37
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I would set it up in daylight and try to focus on something as far away as possible. Check that when you turn the focuser knobs the focuser actually moves in and out. I would always start with the longest focal length eyepiece as it will give the widest view and make finding things easier.

Good luck

Paul

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Hi Nadine,

Definitely try to setup and focus on a distant object during the day. Then you'll get a better feel for it and also it will be 'about right' when you take it out at night, just a small amount of refocusing needed for actual celestial targets should be needed. If you got an eyepiece extension tube, you'll need to use that in the focuser.

If you're seeing multiples of the same star maybe the tube hadn't cooled down properly and / or also needs colminating. But you should at least see a view of Jupiter that looks like a planet. For that you'll want probably to get it centred using a wide field eyepiece (higher mm EP) then use a higher magnification eyepiece (lower mm) to then magnify it so you can see its shape and detail.

You can calculate the magnification by dividing the tubes focal length by the eyepiece focal length. The 200P skyliner has a 1200mm focal length, so for example assuming you got the 2 standard eyepieces then the 10mm gives 1200/10 = 120x and the 25mm gives 1200/25 = 48x. Depending on sky condition you could probably use 200x on Jupiter, i.e. consider another eyepiece when you're ready.

you'd want to try the 10mm eyepiece on Jupiter to see any significant detail. What you'd be hoping to see are 1. some bands, 2. maybe the Giant Red Spot (this is only visible some of the time)

As for stars, they should be pin-points of light, nothing more. If they are blurred check focusing, if they are funny shapes ensure you have allowed the tube to cool down and also check the colmination.

Colmination sounds scary the first time you do it, but really it's a doddle, once you've done it once you'll be re-colminating regularly and it only takes a minute or two.

Other easy targets to practice on are M42 Orion's nebula, M31 Andromeda and the Double Cluster in Cassiopeia - all very well placed in the sky at this time of year :)

Good luck, I think we all have had some issues with new equipment when we start, it's all part of the learning curve and you'll be satisfied when you've got it all sussed out, for sure.

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Hi Nadine, if you weren't able to focus there are a couple of possibilities.

Did you have both the 1.25" and 2" extensions in the focuser at the same time? This is a common mistake that will prevent the scope from focusing. If you are using the supplied eyepieces then you only need the 1.25" extension.

When you were turning the focus wheel, was the focuser moving in and out? If it wasn't, you need to undo the focus lock screw on the underside of the focuser.

Hope this helps.

This will be what it is. Choose either the 1.25" eyepiece adapter or the 2", not both otherwise you won't be able to attain focus.

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If something is not in focus, turn the knob to see which way the out-of-focus blob becomes smaller. If you run out of focuser focusing distance, remove something from the focuser to make it shorter (2" adapter) . If you run out of distance in the other direction, add something, or move the eyepiece a bit outwards in the adapter. If you see stars as dots, then everything is fine and dandy since that means you are not suffering from coma ;) (optical or medical). You were probably supplied with a 10mm eyepiece, with that you should be able to see jupiter as a disc with maybe 2 cloudbands, color , 4 jupiter moons. The Great Red Spot will always be on the wrong side of the jupiter (it is visible maybe 2 hours every 10 hours). With the 25mm eyepiece you were probably also supplied with, you should see wider and dimmer targets ok. m13, m57, m42. Get acquainted with the messier list, it contains many relatively bright and spectacular objects. What you will mostly see in the sky is jupiter, moon, saturn , single stars,double stars, clusters of stars, balls of stars, dim smudges (galaxies) , more dim smudges (nebulas like m42) , small brighter donuts or blobs (planetaries like m57). Only color you will be able to see is in planets  and some rare cases like maybe m42 or blue snowball. 

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Thank you so much to you all for your help!  Turns out I was indeed using both the 1.25" and 2" adapters together, which explains why I couldn't get anything to focus!  I'll make sure to focus my scope during the day too, thanks for all the advice on that as well.  Can't wait to get a nice clear night so I can actually use my scope properly haha!

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