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NexStar 8SE question

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#1 SilentKnights

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Posted 02 February 2013 - 12:35 PM

I have a new NexStar 8SE and when I have the scope angled up at a 45 degree angle on the mount set up and when I pick up the whole tripod and move it. The OTA always ends up pointing at the ground is that normal when moving it or should it stay strong and pointed upward I am very slow and careful when I move the scope on the tripod but it still slowly drops. It slowly just drops from a 45 degree angle to pointing down with very little resistance. When this happens should I turn it back on to point it back up ? Or can I point it up by hand ? Or is this wrong to do ? Is the scope supposed to fall downward easily when moved ? Sorry if this is a silly question but I was just wondering if the scope should always end up in a down position when moving it or should there be more resistance to keep the scope pointing up ? Thanks for any help with this !

#2 Arthur Dent

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Posted 02 February 2013 - 12:45 PM

Hi Steve

Firstly congrats on the purchase of a fine instrument (green with envy).

From what you describe it sounds like the altitude nut is a little slack.

Here is a guide on how to tighten it complete with pictures...

Altitude Nut Adjustment

You can move the OTA up and down by hand as there is a friction clutch in the altitude axis (up/down). Whilst this is not recommended, the occasional movement by hand will not harm your scope. Best to elevate your scope when powered on and using the handset buttons.

The azimuth axis (left/right) is a different thing all together. There is no clutch arrangement on this axis and the drive gears are permanently engaged. Any manual movement in this axis will result in permanent (and likely expensive) damage. DO NOT try to move the scope clockwise or anti-clockwise without the scope being powered up and using the handset buttons.

Hope this helps,

Art

#3 hopskipson

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Posted 02 February 2013 - 12:49 PM

I guess it depends on how much bounce you have in your step. The Alt axis has a clutch that can be adjusted by tightening the nut located behind the plastic housing inside the hand control compartment on the mount. To check if you need adjustment, just point the telescope horizontal to the ground and apply pressure to the corrector end of the optical tube. If it moves without much resistance the nut needs a little tightning. If you need to apply some pressure to make it move then you should be good. If it needs tightning do it in small increments. Hope this helps I'm sure more knowing individuals will be along soon.

#4 hopskipson

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Posted 02 February 2013 - 12:51 PM

I'm sure more knowing individuals will be along soon.


Even as I type! :bow:

#5 Arthur Dent

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Posted 02 February 2013 - 12:52 PM

Posted Image

Art ;)


Steve, if you are new to the NexStar series of scopes, be sure to check out the "Best Of" section at the top of the NexStar forum.

Lots of useful info there - Links and Best of the Celestron NexStar forum

Art

#6 Tel

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Posted 02 February 2013 - 12:55 PM

Hi Steve,

Art's quite right.

But before you adjust, (tighten) the altitude axis nut, refer perhaps to the section in the thread above entitled on the main page as: "Links and Best of the Celestron Forum", subtitled "Useful Forum Threads".

Here you will find a thread describing "Balancing the Nexstar Series" if you're perhaps unsure as to how to do this.

Hoping this also helps,
Best regards,
Tel

#7 Arthur Dent

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Posted 02 February 2013 - 12:58 PM

I beat you too it Tel!

BTW, I think you meant "Altitude Nut Adjustment" as opposed to "Balancing the NexStar SE Scopes"?

Steve: OTA should be balanced (done by sliding the OTA forward/backward along the dovetail). Make sure the scope is slightly rear-end heavy (ie slightly off-balance) so that the gears are engaged (ie under load) with the tube stationary.

Art ;)

#8 Tel

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Posted 02 February 2013 - 01:22 PM

I beat you too it Tel!

BTW, I think you meant "Altitude Nut Adjustment" as opposed to "Balancing the NexStar SE Scopes"?

Art ;)



You did indeed, Art !

But no, I did mean that one needs to balance the OTA off mount before installing it on the dovetail shoe with a little imbalance ! :confused:

I would also add that it is permissible have such an imbalance bias either towards the rear or the front of the tube but, depending on preference and performance, the Altitude GoTo Approach should be set to Positive or Negative respectively.

But obviously the main issue for now is that Steve adjusts that darned nut (NB.in small increments) ! :lol:

Best regards,
Tel

#9 Midnight Dan

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Posted 02 February 2013 - 01:38 PM

Hi Steve & Welcome to the forum!

I carry mine out the same way and the OTA does not move unless I bump it. As the others have said - loose nut behind the wheel! :grin:

Luckily, it's a simple fix. Congrats on the new scope!
-Dan






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