Celestron NexStar 6SE - aligned, but not aligned?

[matsey]

Hi,

This may be a similar/same problem to cpives' recent post, but I didn't want to hijack his thread, so...

I've just bought the Celestron NexStar 6SE and I'm having a little bit of trouble getting the alignment to work properly. It was my second night out last night, and I had the same problem as I had the first night. I admit I am a complete beginner to stargazing/using a telescope, so quite possibly there is something completely obvious I'm missing.

I'm using the three star StarAlign method, and last night I aligned with Saturn, Arcturus and Alkaid. Everything appeared to work OK, and the system confirmed alignment was successful. However, when I then used the GoTo to go to Saturn, although it went to the right area in the sky, Saturn was not centred in my eyepiece, but quite a bit off to the bottom left.

I was able to manually realign Saturn to the centre, but gradually the tracking tracked if further off centre until if I hadn't realigned again, it would have tracked out of view completely.

- I made sure the mount was completely level this time (not sure I was precise enough on my first night)

- I'm using a PowerTank, so not a problem with batteries

- I'm entering the date/time in the US format

Couple of things I'm doing, that I'm not sure I'm doing right:

- I'm using the longtitude/latitude coodinates from my iPhone. Which having checked this morning, is ever so slightly different to Google Map's coordinates for my location. Chris's thread mentioned he used his Sat Nav to get his coordinates, which I didn't even think of, I'll try that tonight (with my Sat Nav, not Chris's!!).

- I'm not sure I'm completely centering each alignment object in the eyepiece, at least I haven't been fully focussing in when I've been doing the centering.

- I aligned the finderscope using a terrestrial object, which because of my limited ground-views was actually not that far away. I'm going to re-do that again tonight with perhaps Saturn.

I did get some very decent views of Saturn, and in the end because of the alignment issue I ended up manually star-hopping with the aid of my iPhone's GoSkyWatch app to identify what I was seeing... which I have to confess I really enjoyed, so I'll be doing much more of that anyway even after I sort this out.

So, tonight I'm going to try my sat nav's coordinates, more accurately centre star in full focus, and also the finderscope to.

If anyone has any other suggestions, I'd really appreciate it.

Thanks,

Matsey

[smudgeball]

Hi there

You've already covered off a lot of things that I would have suggested.

I've had evenings when alignment has not been great but usable.

One tip I got off this forum is to use targets as far apart as possible.

So if say your viewing area is a 180 degreee area or so in your back garden, use a target far left, far right and then one in the centre, but high up.

Give the "goto" a lot of work to do to align.

If I've got good seeing, I like to use auto two star align and set my targets to the absolute viewing extremes.

I then get really good alignment on all other targets for the rest of the evening.

Something to try ??

Cheers

Neil

[Roy@Aldermaston]

I have a Nexstar 4SE, which was a pain to align at first. These are a few things that might help:

Make sure the OTA is balanced and the tripod levelled.

Don't use a planet as one of the alignment objects, always use stars.

When centring objects in the eyepiece, approach in the same direction that the scope uses in its final GOTO - in the eyepiece you should move the object down and to the right. This helps to minimise backlash.

It may help to select solar system tracking rate in the handset menu, can't quite remember where the option is, as opposed to the default sidereal rate.

Hope this helps,

Roy

[DoctorD]

Hi centring the alignment star in your highest magnification eye piece will make a big difference.

Clear skies

Paul

[matsey]

Thanks all, some really good suggestions there. I'll give them a go tonight, and will report back how I get on

Just to add... I have just checked my Sat Nav and although the latitude is spot on the same as the iPhone reading I'd used, the longitude has me 09 west on the Sat Nav, and 09 east on my iPhone. The google maps settings are closer to my Sat Nav, though still an additional 03 north. I think I'll go with the Sat Nav co-ordinates as I'm thinking they'll be the most accurate... fingers crossed

[matsey]

update:

feeling a tad disappointed right now, tried all the suggestions - correct gps co-ordinates, didn't use Saturn this time, centered using highest mag and chose stars as far apart as I could, but I'm still not getting a centered view after alignment.

I am definitely not giving up with this, but I'm just not sure what else to try. It almost feels like in the time it takes to confirm the alignment, everything's tracked out of view... on the last attempt the third star I aligned was Vega, and even after alignment I told it to goto Vega, it sent it completely out of view! Ahhhhh !!!!

Two things I've just remembered I didn't try... the two-star alignment instead of the three star alignment, and I also didn't try changing the tracking mode to solar system, so I'll give those a try on another night.. I've got work tomorrow and I really need to send myself to bed !

Thanks for all the help so far, I know I'll get there, no giving up from me !!

[matsey]

One question, something just occurred to me, regarding entering the time...

Say, the time is 10.00pm. I am entering the time as 10.00pm, then selecting UTC as the timezone, and then Daylight Savings for BST.

Just clutching at straws here now, but do you think I should actually be entering the time as 9.00pm as that is the "true" UTC time, with the Daylight Savings option taking care of the fact it's really +1?

Thanks !

(lol, just noticed I've been promoted from a Vacuum to a Nebula... I quite liked being a Vacuum, it rather made me laugh!! )

[Demonperformer]

Hi, matsey

Just found this thread. If you are still having problems, I could never get the three star alignment to work satisfactorily. I tend to do a one-star align, then GOTO a second star and use the align button to add it as a second alignment point. Seems to work OK. As for entering the time, you could always enter the 'GMT' time and tell it you are using UT and not DST.

HTH

[matsey]

Houston, we no longer have a problem !! We have, finally, success !!

A fair few cloudy nights over the past couple of weeks have prevented me getting out much, getting dark late combined with having to get up early for work didn’t help either. But, finally, last night I was rewarded with a beautiful clear night, so off I went with my notes of things to try and a determination to not go to bed until I’d got this thing cracked. And crack it I did ! Hoorah !! :D

My original plan was that I was going to continue this post with a more detailed description of everything I did to get my alignment process working, to give something back and hopefully help future/new NextStar 6SE owners. However, having written it all out first in a separate window, I realised I had written SO much, it would probably be too much for a single thread post! So onto plan B.. I've turned all that into (my very first) blog post (linky linky, for those who do want to read more: http://stargazerslounge.com/blogs/matsey/821-celestron-nexstar-6se-learning-how-align.html).

So thank you, so very much, to everyone who has posted and for all the advice I’ve received, it really did help a massive amount.

Probably need to get off my computer for a bit , but I will definitely post a First Light report in the Observing forum a bit later, as I really did have a most amazing night with my scope last night (I know not strictly my first night out, but as it was the first night really using the scope to view objects and not just getting the alignment working, it feels like my first night, so that's how I'm going to treat it )

Happy Skies :D

[thelostboson]

Thank you for starting this post and your blog. I have had the same problem, and hopefully want to try this fix for alignment as soon as the sky is clear!

Your original link did not work, but I found it here: http://stargazerslounge.com/blog.php?b=821

[M4lcs67]

edc

[Coedybrenin]

I have just found this thread and found that matsey had the same problem as me in that I have taken my celestron 6se out a couple of times and despite going through the alignment procedure, checking the powertank ok, Dateformat MM/DD/YY ,level scop, correct GPS co-ords , after doing 2 star align on stars 2 opposite sides of the sky, the scope does not slew correctly to known stars- when I try and slew back to 1st star aligned to it misses it

I noticed a couple of iinks in the thread to help pages but they don't seem to work, Any chance they could be reposted or sent to me to so I can check the process again

Many Thanks for any help

Coed-y-brenin

Celestron 6SE

[LukeSkywatcher]

I have an 8SE and the only alignment i do is a "Solar System" alignment. This is usually with the Moon when visible, or a planet when the Moon is not in view.

Its impossible to centre a target perfectly with a RDF, so targets will always be a bit off in the FOV. That is easily fixed with a bit of manual slewing.

My 8SE is a year old and the first time i used it, was as a test. I aligned the Moon and went to watch tv for about 90 mins. When i returned to the scope, the Moon was still in view..........not perfectly centred but still well within the FOV.

[CSM]

There is a very good utility for finding the best alignment stars on the NexStar Resource site. It actually gives you 2 which are the ones furthest apart - you can use any other star which is on the list of alignment stars for the 3rd one though you may get away with a planet or even the Moon. However, if you are only going to look in one small area of the sky then just do a one-star alignment. I find that works just as well as the 3 star - indeed over quite a wide area of the sky if you choose one that is 'central'. As for not being central or even finding it, that is not unusual. I use a 9 x 50 finderscope as it gives a wide field of view and I can see where in which direction I need to move the scope in order to get it central. As for tracking I find that, having centralised the object, setting the slew rate to 4 or 5 often seems to do the trick - it shouldn't and it is probably simply imagination as it is supposed to be going at the sidereal rate anyway.

[matsey]

Hi all,

Apologies - I've only just seen there have been new replies to my old post - certainly brings back some memories of my initial alignment woes ! I can say though that it definitely gets easier. I'm normally now up and running in less than 5 minutes (plus 5 for the initial bringing scope outside, leveling and allowing to cool), so please don't give up

After MUCH searching, I finally found the link to my original blog post - I presume the url changed following the site redesign that happened at some point last year. Here it is now: http://stargazerslou...g-how-to-align/

Just reviewing back over that blog post, I'd probably highlight these as being the most important/useful:

• Accurate longitude/latitude
  
• Remember date format ! MM/DD/YY
  
• Align first with low power piece, and fine-tune align with a high power piece (I ended up buying a special 9mm plossl that has an illuminated cross hair to see where exact centre was - a bit expensive around £80 if I remember rightly, but it saves quite a bit of time and increases the accuracy so I personally think it was worth it)
  
• Prefer two-star align to the skyalign function.
  Even now I still find the skyalign fails as often as it succeeds. The two star align does require some knowledge of night sky, but once identified you can use the same two stars for a good few months before needing to choose another pair, so it is worth the time to find a couple of named stars. To use the skyalign though it actually somehow helps to be in a slightly light-polluted sky as (I have found!) in a true dark sky site there are too many bright stars and most of them aren't in Celestron's alignment stars list ! CSM I see has linked to the list Celestron use as alignment stars, so you if make sure you choose stars from that list you should be OK.
  
• Don't use a planet as one of the two alignment "stars"... unless of course you're only planning on planetary observing, in which case just use the solar system align, that will work more than adequately.
  
• Don't use batteries - use a power tank ! I use one of the jumpstarter type from Maplins (cost around £30), and has worked just fine for me.
  

Not sure if there were other links that aren't now working (I did a quick re-read and couldn't see any?), so do post back and I'll see if I can remember where they were supposed to go to.

Hope that helps a bit, and more than happy to pass on any extra knowledge I've gained over the last 18 months

Matsey

[Thingy]

I've got an 8SE and had similar problems, eventually I found:

It really does matter whether the tripod is level

It's vital to get the finderscope working and make sure the alignment stars are dead centre in eyepiece

The time is correct

The location is correct

and not get confused as to what Daylight Saving actually means

I also discovered that using the batteries would cause problems whereby you'd try and get the scope to go some-place but as it moved , the batteries can't sustain the flow and so it would almost get to the destination and then plop-out whereby it starts zigzagging all across the sky towards random points.

Another thing is that its not such a good idea to use the tripod as a method for keeping balance, I'm dyspraxic (difficulty with movement) and so standing in the dark isn't so easy. One night I squished my fingers between scope and base of the mount. I then found that the GOTO mechanism had goofed up as the computer thought it was moving the scope and didn't know about my fingers being in the way stopping it from moving - it thought it was looking in the right place but it was a few degrees out - everything worked hunkydorey again once a power reset was done.

[Dunkster]

Another tip for centering the stars in the view when aligning.... use a narrow FOV eyepiece like the supplied plossl and when you have the star in the FOV, dial it out of focus. What I do is to dial it out of focus enough that the star becomes a big donut almost large enough to fill the view but not quite. With this combination of things, I find it much easier to centre the star as you can easily see the edge of EP FOV and easily judge how well the donut fits in it.

I've found this to be generally quite effective, but if you also have a shorter focal length plossl to had then that helps make it more accurate, as mentioned before.

Btw, I've noticed it's more fussy about the time being accurate - I use Emerald Sequoia's Time app on my iPhone to get this as close as possible. I've also noticed its less fussy about the exact location...it's normally set to home, but I've gone out with it and not modified the lat and long without noticeable consequence (albeit not that far)

Finally, alignment method... I use auto two star align and find it's as accurate (or not) as the others, but a lot quicker to get going. Depending on season and location, I tend to pick Polaris as first star (it's always where you expect it to be!) and then select a reasonable one from the list it shows. For just a quick look at a planet, I've used Solar system align quite a bit, as its very quick to get going, but just expect to make minor adjustments along the way.

If you want to use sky align, select 3 stars far apart in the sky as mentioned earlier, but make sure they are not in a straight line, but form a triangle in the sky. When I've used it, I pick bright stars between 30 and 70 degrees altitude (but all 3 at different altitudes) and at least 90 degrees azimuth apart. Use Stellarium or similar before your session to help pick them - planning is the key

[Cosmic Geoff]

I have a Celestron Nexstar 127 SLT (Maksutov) which I have had for a few weeks. 

I struggled at first to get it to align properly, but I think I've got the hang of it now.

I never got the three-star align to work well, but I was advised that the 2-star align and two-star auto align work better. And this turns out to be the case.  On the last few observing nights I have used two-star align without any bother and been pleased with the results.

Novices may wonder how accurate the electronic system actually is when it's working properly: read on:

I align using the low-power eyepiece (25mm) and two stars e.g. Capella and Regulus. On commanding the scope to find an object, it mostly appears in the middle of the low-power eyepiece field. After an hour of trying out the Sky Tour I told it to find Jupiter. Which appeared centered in the middle of the 25mm eyepiece field. In about an hour and a half I successfully found and viewed a dozen objects.