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Hi all, just purchased my first scope, it's been a rollercoaster ride trying to decide, i'd done a lot of reasearch and told the friendly guys at Bintel (Melbourne) to put my name on a Celestron 6se, i went to pick it up Saturday and after some more advice i changed my mind and ended up with a Meade 12" light bridge lol, it came with a 26mm EP and i purchased an additional 16mm and a barlow along with a laser collimator, now all's i need to do is work out how to use the blumming thing, any advice about this system would be greatly appreciated. cheers.

Edited by Defender

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That's an awesome first scope you have there!

A dob is about the most straightforward design you can buy. Set it up, wait a bit for it to cool down, then point it at the sky. It's that easy.

Now all you need to understand how to find the more interesting objects. :)

I'm sure others will be along with alternative recommendations, but I use Stellarium and Turn Left at Orion.

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Hello and welcome to the lounge. I agree with ajg, an awesome first scope. I'll second his recommendation for Stellarium and Turn Left at Orion as well. Best of luck!

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Unfortunately, "Turn left" only has a small section on southern hemisphere objects, but you should get some excellent views of the LMC, SMC, Omega Centauri, Eta Carinae, and a good load more.

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Thanks guys, i've never used a scope before, i set it up saturday night, there was bit of LP, i had no idea of where to point it and i never really gave my eyes a chance to aclimatize, the stars looked like little rings with another ring around the outside, i didnt see anything interesting, i had no computer access so i couldnt use stellarium, i just wanted to have a quick go and make sure everything worked.

collmination, i collminated the diagonal mirror first but after doing the main mirror the diagonal would be out (is that normal?)

I'll be seting it up again tonight, should have fairly dark skys, i might have look for some planets. cheers.

also, is it normal to see the cross housing of the diagonal mirror through the EP at certain angles?

Edited by Defender

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The stars should resolve to pinpoints if everything is correct.

Check that your laser collimator is correctly collimated - easiest way to do this is not to tighten the focuser all the way down on it, then rotate the collimator. If the beam moves around on the primary, the laser is not collimated, so you'll never be able to align the optics with it.

To do the collimation right, you need to go through several stages:

1) Secondary alignment with focuser

Ideally you need a sight tube for this because the laser is no good for this stage. Basically you are ensuring that the secondary (diagonal) is centred under the focuser, and centred within the OTA.

2) Secondary alignment with primary

Now using the laser, adjust the secondary so the beam lands in the middle of the centre spot on the primary. It's worth checking that the centre spot actually does mark the centre. There have been a few scopes where the marker has been misplaced ...

3) Primary

Once the secondary is centred and aligned, it's a simple matter to adjust the primary until the return path of the beam lines up precisely with the outgoing path.

You can go to the nth degree with collimation, ensuring that everything is spot on, but with a truss dob, it's pretty futile as the alignment will wander slightly every time you set it up.

There's a good post on CloudyNights all about collimation.

Edited by ajg

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Awesome first scope Defender:icon_salut:,I remember mine was a 60mm Tasco refractor,I seriously considered getting a LB but settled on a 10" PX tube Skywatcher Dob that should arrive tomorrow.

All the best with the LB.

Jon

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The stars should resolve to pinpoints if everything is correct.

Check that your laser collimator is correctly collimated - easiest way to do this is not to tighten the focuser all the way down on it, then rotate the collimator. If the beam moves around on the primary, the laser is not collimated, so you'll never be able to align the optics with it.

To do the collimation right, you need to go through several stages:

1) Secondary alignment with focuser

Ideally you need a sight tube for this because the laser is no good for this stage. Basically you are ensuring that the secondary (diagonal) is centred under the focuser, and centred within the OTA.

2) Secondary alignment with primary

Now using the laser, adjust the secondary so the beam lands in the middle of the centre spot on the primary. It's worth checking that the centre spot actually does mark the centre. There have been a few scopes where the marker has been misplaced ...

3) Primary

Once the secondary is centred and aligned, it's a simple matter to adjust the primary until the return path of the beam lines up precisely with the outgoing path.

You can go to the nth degree with collimation, ensuring that everything is spot on, but with a truss dob, it's pretty futile as the alignment will wander slightly every time you set it up.

There's a good post on CloudyNights all about collimation.

Thanks for the lnk ajg, the collminators fine, doesnt make a circle at all, ive been reading some reviews on the scope and most say it's a very hard scope to collminate the first few times (to get it 100% anyway), most say the more you do it the better you'll become at it.

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I can totally recommend that you aim your new scope at the Jewel box in the Southern cross. I've been lucky enough to get a few views of it from here, South of Hong Kong, where it appears very low in the sky on only the clearest of summer nights. I can only imagine how beautiful it will appear from so much further South.

yeti-monster-albums-yeti-monsters-e-sketches-picture4969-jewel-box-e-sketch.jpg

Edited by yeti monster

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A very useful book for us southern observers is E J Hartung's Astronomical Objects. Most of the observations were done from NSW I believe. Some of the text and pics may be a little outdated but it is still a useful resource.

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