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Help setting up my new telescope (Complete Newbie here!)


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Well, I'm new to the forums and this is my first post.

I've been interested in astronomy since long ago, but just a few days ago, I got handled a telescope, I've tried gazing at the Moon and seen some really neat views, but when I pointed at Jupiter I could just see a really blurry ball, and it wasnt out of focus, started reading on the internet about getting started with reflectors and learnt about this collimation thinguie, so I gave it a try (I swear the mirrors weren't well-placed either before tinkering with them) but I think I've just screwed it up more, now all the mirrors are even more misplaced than before and I've been trying to get them into place for hours.

Is there some sort of straighforward procedure to collimate? I've been browsing the internet for a while and I've just found posts of people using collimation eyelenses and laser collimators, which I, neither have.

And btw I forgot to mention it, the telescope model is a Celestron Powerseeker 127 EQ (Newtonian reflector).

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Simple start: make a collimation cap (google it). Remove eyepiece and look at the secondary. Get the secondary to look perfectly round (not elliptical) and centered in the EP tube. You may have to loosen the center screw to get it centered in the tube. Carefully (no prints on mirror) reach through and hold secondary and tighten center screw. You may have to slack the 3 screws a little.

Put collimation cap in the place of the EP, and sight through the hole Look at Astrobaby link to go from there. Once everything lines up as shown in her pictures through the collimation cap, you've got it.

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Danilon, the general possibilities for a 'blurry-ball' Jupiter are poor collimation, poor seeing conditions, poor focussing, using too much power, or the eyepiece really is bad.

I do not own or have any experience with your scope, but I think the Powerseeker 127 has a 'bird jones ' design. This means it has a magnifier built into the focuser, so although the scope's tube length is only 450mm, its actual focal length is something like 1000mm. This does raise a number of issues, not least the question of collimation. If you investigate a little, you'll find ways to collimate such a system but just for the record, lasers won't work with Bird Jones reflectors, so the best approach is to do something like a star test, and collimate with a cap or a Cheshire eyepiece.

The other thing worth bearing in mind is that so long as you're using magnifications of between 100x to 150x, Jupiter is quite low now, so when viewing you're having to cut through quite a lot of atmosphere. This will affect Jupiter's image quality in the eyepiece and the 'seeing' may be quite bad. If the Moon looks sharps, stars look tight, and Jupiter looks blurry, it may be just a case of bad seeing. To counter this doubt, check out Saturn and see what affect you are getting there.

I'm sorry I haven't been able to help more :smiley:

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If the secondary mirror that you see through the focuser tube is concentric within the focuser tube, ie. equal space around the mirror in relation to the focuser tube, then so far, so good. If ok, can you now see the 3 supports that hold the primary mirror (still looking through the focuser without an eyepiece ) If you can just see the 3 black edges of the mirror supports appearing from the edge of the focuser tube, then all is ok? The mirror is not parabolic, and even after centre spotting my scope and collimating using all methods available, you will achieve no better collimation than with your eyes alone. A 1mm hole in the eyepiece dust cap is all you need for a collimation tool? This only enables one to align the eye with the mirrors central axis. If you go to the Celestron site, you should be able to download the user guide. Dont be fooled with the image of Jupiter on one of the pages, the Celestron 127 is not that good!

I read this telescope was gifted to you?, save your money for eyepieces and accessories for your next telescope? Even with better eyepieces and best collimation, the limited ability with this particular scope shows more than the targets you see, and you should not be wasting time having to constantly adjust the basic EQ GEM mount, just for visual use!

That aside, if the scope is setup correctly, and polar aligned, the Moon will look great. The Planets will be harder to achieve any clarity, due to the size of the final image and the weather / seeing conditions your looking through.

I wish you well in your early days with this telescope, and advise you to compare what you already have with the Skywatcher 6" Dobsonian as your next minimum upgrade?

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Do the secondary mirror first - it should look perfectly circular when you peer down the focus tube - usually through the small hole of a collimation cap. You should also be able to see all three of the primary mirror clips holding it in place before collimation the primary. Hth :)

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Do the secondary mirror first - it should look perfectly circular when you peer down the focus tube - usually through the small hole of a collimation cap. You should also be able to see all three of the primary mirror clips holding it in place before collimation the primary. Hth :)

I finally managed to kinda center it, now I see all the three primary mirror screw clips, I attempted doing that "star testing" thing and in every single star theres blur on the left-bottom side, it's clear on the other sides, but it's was as if some of the light was leaking to the left.

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If the secondary is looking like a perfect circle in the collimation cap - then also look at it square on with the focuser tube empty. It has to be a perfect circle both ways. Also look down the open end of the scope along a central line - the secondary will appear as a perfect black circle there too if all is correct.

You'll see all three primary clips easily. I use a laser to fine tune the beam dead center on the primary using the secondary screws. Then loosen the lock nuts of the primary and adjust the beam using the three collimating screws to ensure it is coming back along itself and hitting the same spot where it left the secondary.

Then it's just a fine tweak of the primary to center the beam on the laser target. In the star test - get as good a focus as possible on the star - then take it slightly out of focus first one way then the other. When just out of focus you should see some faint rings. They all need to be dead concentric - if they're skewed one way or other - then you know there's still some misalignment. :)

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If the secondary is looking like a perfect circle in the collimation cap - then also look at it square on with the focuser tube empty. It has to be a perfect circle both ways. Also look down the open end of the scope along a central line - the secondary will appear as a perfect black circle there too if all is correct.

You'll see all three primary clips easily. I use a laser to fine tune the beam dead center on the primary using the secondary screws. Then loosen the lock nuts of the primary and adjust the beam using the three collimating screws to ensure it is coming back along itself and hitting the same spot where it left the secondary.

Then it's just a fine tweak of the primary to center the beam on the laser target. In the star test - get as good a focus as possible on the star - then take it slightly out of focus first one way then the other. When just out of focus you should see some faint rings. They all need to be dead concentric - if they're skewed one way or other - then you know there's still some misalignment. :)

Same here, although I check back with the collimation cap, and look down the tube at the path of the laser. Make sure the laser is collimated first.

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Absolutely Kalasinman - but I didn't want to confuse a new chap with collimating lasers lol. :)

it's a tough call, I agree, but on the chance that I might save him from a frustrating failure.....I had to go there. I believe it's a fair assumption that any laser under say $100 may well be out of collimation. There are so many simple ways to make v blocks (including nails in a board) that it's easy to check it. Mine was off a mile and once carefully done, it stays on nicely. I guess a quick way is to put the laser in the focuser and loosen it just enough to be turned. Turn on and watch the spot through the front of the scope as you rotate the laser. If it stays in one place, you're good to go. If not, make v blocks and collimate it.

Before looking in the end of a scope with an active laser in the focuser, hold a piece of paper in front of the aperture. If you see a laser spot, then don't look in there. The spot is safe if it's striking the secondary, but not if it isn't.

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