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Understanding the view through a telescope

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Hi guys

Awaiting delivery of my first scope (8"dob) and need a bit of help to understand how the image appears through the scope and view finder.

Is the image I see through the eye piece upside down / back to front / or left to right or even a combination of all three.

Also is this the same through the finder scope ?

Just want to try and get my head round it before I get started.

Kind regards


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Welcome to SGL Leigh. Hope you enjoy your stay.

Up and down, and left and right are reversed.

Stars will move from right to left in your eyepiece, ie appearing to move west to east. If a star seems to drift north in your eyepiece, you will need to move the scope down to centre it.

It is confusing at first, but you will soon get the hang of it.

A good ploy is to imagine you are actually moving the star in the direction you want it to go.


Edited by barkis
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When trying get something into the field of view or when trying to keep it there, don't think about which way to move the scope, think of holding the object (star, planet, neb, cluster etc. etc) and moving it into the centre of the FOV whilst holding onto the scope. Thus hold and move the scope but imagine that you are holding and moving the star, planet etc. When you think of it in this way, the upside-down/back-to-front issues disappear.

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And patience is a virtue with this hobby, don't rush it, manage your expectations and be absolutely guaranteed that bit by bit it gets easier, quicker and more rewarding.


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You are in for a world of fun -- congratulations on your 'scope purchase! As Richard writes, there's a LOT to learn, so take your time and have fun.

In addition to the image being reversed, with a Dobsonian you might stand to the left or right, and many models allow you to rotate the tube, so it will be confusing at first. If you use it for terrestrial viewing, like watching birds on a wire or branch, you'll see birds hanging upside-down and at all sorts of odd angles. You learn to completely ignore this after a while, and soon you won't even notice.

After many years of observing, I don't pay much attention to the direction stars appear to be moving across the view while looking in the eyepiece -- I look at the chart, tilt it if needed to match the sky orientation, and I prefer to think about where the front of the tube is moving, not what appears in the eyepiece. If I need to go "a little up and then off to the left" from a bright star, for example, I would get all confused trying to reverse all that in my head; I simply move the front of the DOB a little up and off to the left, and with some experience, you'll learn to relate the distance on a star chart to the field of view of a low-power eyepiece, or the FOV of the finder.

You'll have a lot of help and encouragement here, so you won't be alone.

Clear skies,

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I still get it wrong now lol, when looking into the finder scope left is left and right is right, then as you look into the scope to see the great sight that is Saturn, your see it move, quite quickly to, say to the left as you look at it, so you go to move the scope to folow it and push the scope to the left as well and watch it shoot past the other way!! left is now right and right is now left.

It all sounds a bit crazy but your soon get it, but like i said still catches me out sometimes.

Another thing if you look at maps of the moon your notice it dont look the same as looking at the moon with the naked eye....upside down again same with planets, dont worry your get it, it really is fun

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Thanks very much guys

I've never been on a forum before (and I've been a member of a few) were everyone is so helpful and quick to respond.

Really looking forward to the learning curve ahead.

Very much appreciates, regards


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