Nexstar alignment: getting it level

[kevenh 16]

So the little circular bubble level is weak.

But how to improve the levelling stage a head of the alignment stage?

A traditional level like this one

Or a simple multi purpose one like this one?

And we do this on the tripod before adding the mount & OTA?

The mount looks gently curved. How do we check that for level or do we trust the ‘fit’?

[Peter Drew 11,314]

If you get Michael Covington's book  "The Nexstar Users Guide" he explains why levelling is a myth and not necessary.     

[cloudsweeper 6,471]

I just use that little circular one.  Even if it's not essential, it only takes a minute to do.  I tend not too get too worried about alignment, and generally use one-star or planetary with a good degree of success.  (If slewing further afield, I might use two-star.)

The best aid for quick, easy alignment is the GPS module.

Doug.

Edited October 11, 2020 by cloudsweeper

[kevenh 16]

Thanks for feedback
It helped me find this discussion.

But that was not a clear defence of not levelling.
I own a metre long spirit level. I’ll add a decent smaller spirit level and use that for astronomy while I learn about my nee scope’s foibles. 
 

edit. I’d like the nexstar GPS add on.  Maybe later when I’ve got the basics working/learnt.  No short cuts - well, except one coming up in the Prime sale this week

Edited October 11, 2020 by kevenh
Credit other advice

[Cosmic Geoff 1,341]

Leveling the mount is only critical if you are relying on a one-star or planetary align.  Otherwise you can get away with the mount just looking level, eg if you have set up on concrete that is supposed to be flat.  The C8 SE can be carried out in one lump, which is a reason for not taking the assembly apart to accurately level it.

With the Celestron SE mount, to level it you are meant to set the little bubble level on the machined top surface of the tripod (the only true flat surfact in the outfit), which admittedly is a bit of a faff.  I'd do this only  if setting up on uneven ground or if intending to use the solar system align.

[Peter Drew 11,314]

I've never bothered to accurately level my C8se, I just plonk it down.  I've often been called a plonker!     

[kevenh 16]

Thanks for more feedback.

My head now knows that Nexstar can align if not dead level but I'll still try for that

My alignment needs improving elsewhere.

The best I had it was via a Skyalign using two unknown bright stars as #1 & #2 and Mars as bright object #3.

With that I had a 'success' from the HC and could Goto Uranus & Saturn.  Then back to Mars.  Which was in my 22mm EP but not dead centre.

[Neil H 645]

If levelling is not important  why does the manual tell you to level the mount using a spirit level . I use the one in your first photo what they call a boat level due to its shape 

I would had throught by not levelling the mount you will introduce cone error in the tracking of an objet 

The goto was not spot on with my HEQ5  now i use a cross hair eyepiece  and 3 star alignment its very close i also found clear PAE and retrain the PAE makes it even better 

Your goto may have a PAE that can be cleared and retrain which may help a lot 

[Cosmic Geoff 1,341]

1 hour ago, Neil H said:

If levelling is not important  why does the manual tell you to level the mount using a spirit level

Probably because it makes for simpler instructions.  As discussed above, the alt-az mount does need to be accurately leveled for a 1-point (1-star or solar system) alignment, but as various people have found, not for multi- point alignments.

The alt-azimuth Nexstar and equatorial Sky-watcher Synscan systems differ significantly, so cross-comparisons are not necessarily valid.

[Neil H 645]

Ok was just thinking about what happens with mine 

[Peter Drew 11,314]

Equatorial mount setup is a different matter as cone angle can then come into play.    

[Neil H 645]

Very true i did see a drawing on a thread about how they track in steps love this hobby always some thing to learn 

Edited October 12, 2020 by Neil H

[jonathan 642]

When I had my SE goto mount I stuck the little circular bubble level to the accessories tray (near the middle), I probably confirmed it's accuracy at the time with a small traditional level like the first one linked to.  Both of my EQ mounts have the same small bubble level and it seems to work fine for me.

[Peter Drew 11,314]

Think of levelling this way.  You level your mount, go through the alignment sequence and your goto works fine.  At the same time, a user 10 degrees South of you does exactly the same thing and the goto works fine.  Yet the level of the second telescope is 10 degrees out compared to yours yet still provides the same result.  No harm in levelling an alt-azimuth goto mount but as long as it doesn't fall over, the goto will work.  The star positions relative to each other, the basis for the alignment, are not variable.