Nexstar 8se alignmmet

[madasadad]

I’ve had my 8se for a few weeks and opportunities have been limited however I have been impressed with  the views I’ve had when manually going to objects however I’m getting totally frustrated with the alignment process, I’ve never had a successful alignment and I’ve tried every option! Most frustrating is that the well know stars aren’t listed as options, Capella, Sirius, Polaris etc.  My skies are quite polluted so I can only easily get the main bright ones, none of which are listed as options! I’ve checked gps, time etc etc and fail every time! Except tonight I opted for solar system align and went to mars, align successful! Woo hoo, goto Neptune, but instead of the scope  going right and down, it ended up left and down and considerably away from where it should have been! I had originally mounted the Ota that when level the tightening knob was at 12 o’clock instead of 6. I’d hoped that would cure it but no chance! The scope lags behind.  I always finish alignment right and up, but in the eyepiece it looks left and down .  Any thoughts? 

The yellow x shows where the scope went instead of where it should have gone! 

[michael8554]

Is that where Neptune would have been an hour earlier?

Maybe got Daylight Saving on ?

Michael 

[Cosmic Geoff]

3 hours ago, madasadad said:

Most frustrating is that the well know stars aren’t listed as options, Capella, Sirius, Polaris etc.

If the GoTo is misbehaving in a consistent pattern, it is 99.9% certain that incorrect settings, i.e time & date or latitude and longitude are to blame. 

It is a while since I did an alignment with stars manually, but if no useful stars are showing on the handset, it suggests that you have some settings wrong.  Like the time (daylight saving should be off, and use 24 hour clock) the date (USA format) or the latitude and longitude entered wrongly.  Once you have entered the lat & long (wrongly or otherwise)  it can be a pain to figure out how to access the part of the menu where you change them.  (I think you start the setup and then hit Back a couple of times.) But you should be able to use the menu to check the lat & long that are entered IIRC. 

Once you have the right settings entered, the GoTo should work pretty well with a 2-star align. 

[Ruud]

I prepared a list of which alignment stars are for which mode of alignment.

In the list ...

• All stars are for Two Star Alignment and for Sync.
• Stars with an asterisk ( * ) are for Auto Two Star Alignment and One Star Alignment.
• Bold stars are for SkyAlign.

One thing that definitely helps is an 8x50 RACI finder.

The list: NexStar Alignment Stars.pdf

I also have a spreadsheet  with the same data. You can apply filters for brightness, declination and such things and sort the data in various ways.

For sorting by position use the decimal columns for declination and right ascension.

The spreadsheet: Align-Nexstar 2.xlsx

[Demonperformer]

9 hours ago, madasadad said:

I had originally mounted the Ota that when level the tightening knob was at 12 o’clock instead of 6.

My OTA is mounted so that, when it is pointing downwards (focusser knob on the top), with the mount arm towards me (looking at the handset in its slot), the tightening knob is on the right.

10 hours ago, madasadad said:

My skies are quite polluted so I can only easily get the main bright ones, none of which are listed as options!

Avoid the AUTO alignment option, but select 2- or 1-star alignment (if you use 1-star, then add an additional alignment point manually afterwards). This way you can use any star that is (I think it's more than 10/15 degrees) above the horizon. Or you can use skyalign, which uses three "bright objects" - you don't even have to worry about what they are.

As Geoff has said, your basic settings must be right (date format is a favourite error) or the computer will get confused.

[JG777]

Lots of info here  https://www.nexstarsite.com/AlignmentFAQ.htm

Date set in US format?

Time accurate?

DST settings correct?

Input co-ordinates in custom site as degrees minutes and seconds and N/S W/E settings correct?

 

Use stars above 20 degrees and below 70 and as far apart as you can manage. Auto 2 star should nail this and is quicker and more reliable than Skyalign.

 

[madasadad]

Thanks folks, all settings are correct, which makes me even more frustrated!  I tried solar system align this morning, successfully on venus, and heard the motors tracking, however within 10mins, venus had moved considerably and the scope only slightly.  Ive adjusted the backlash to 10 and always finish up and right.  Ill keep on practicing, hopefully it'll come good for me!

[madasadad]

Mirach is high in the sky at the minute, what would be a good second star for alignment?

[Cosmic Geoff]

5 hours ago, madasadad said:

Thanks folks, all settings are correct, which makes me even more frustrated!  I tried solar system align this morning, successfully on venus, and heard the motors tracking, however within 10mins, venus had moved considerably and the scope only slightly.  Ive adjusted the backlash to 10 and always finish up and right.  Ill keep on practicing, hopefully it'll come good for me!

But it's still not working?

Here are some actual settings for a Nexstar+ handset finding Mars this evening (19th Dec) at 5pm:

Solar Sys Align,

  16.57.27 

Standard Time

12/19/18

Select Object:  Mars

Centre Mars (enter)  (and do the centering, obviously)

Align Mars (align button). 

And extracted from the "menu", "scope setup", "Custom Site":  (actually I have substituted the figures for Belfast here.)

Longitude  005 55 035

  West  

Latitude 054 036 028

North

If you are entering something significantly different, that could be your problem.

If you don't complete the align procedure properly as shown here, the mount will not track...

 

[jonnydreads]

hi, just to check... you're not using batteries to power the motor are you? I have the nexstar 8se and it never goes where it should with batteries! and they only last an hour, just checking your using a power pack?

[impactcrater]

it is always frustrating at first , speaking from experience and note it is not a mechanism that is 'spot on' . two star auto is best in my opinion and I learnt that from a tutorial on the net . find a known star earlier in the night so that it is bright and the other stars do not confuse you . when you can just see the first stars is a good time. auto 2 star will then ask you to chose a second star and I base that on looking at stellarium . I like two stars that subtend a  'sensible angle'(a slight roatation of the head)  in a reasonably horizontal plane.

let the scope sit on these stars to allow it to darken up and every now and then go out and fine tune to the second star (or the first if you prefer)

as the night goes on and it darkens and you start looking at other objects ( chose bright things ) you will find the accuracy improves

remember it is not an exact system and you will have to use the finder scope to bring things into accuracy

PS

the planets and moon are not good alignment objects unless you just want to watch one object

[Demonperformer]

7 hours ago, impactcrater said:

the planets and moon are not good alignment objects unless you just want to watch one object

I always found that they made a good FIRST alignment point, but you do have to get the time spot on. Really easy to find and there is no mistaking them when they are in the eyepiece. BUT for a general session, you will certainly need another point. Starting at your planet, GOTO another bright object (this does depend on  getting the scope to move in the right general direction!). Centre it in finder/eyepiece. Then hit the ALIGN button - I think it's three times - and your second alignment point is fixed. Be aware that hitting the align button switches off the motors, so the object will start to drift, so you need to complete these three times quickly - otherwise you are back on the "centre it in the finder" etc routine. This is a thing that always annoyed me about the SE alignment procedure - there is no option to say "I have the object centred in the eyepiece, just accept it, you stupid machine" ... or words to that effect.

[Anne S]

I owned a 8SE for quite a few years. I also never managed to get skyalign to work. I found out later that one of my stars wasn't bright enough. I switched to auto two star alignment and never looked back. It's quicker too.

[madasadad]

Thanks again, i may have encountered a schoolboy error and enter lat/long baxk to front, which means the scope thought it was in the north of brazil! Of course the weathers been rubbish since, so have no idea if im correct or not!

[Demonperformer]

That would certainly produce some weird results.

[Astro Imp]

2 hours ago, madasadad said:

Thanks again, i may have encountered a schoolboy error and enter lat/long baxk to front, which means the scope thought it was in the north of brazil! Of course the weathers been rubbish since, so have no idea if im correct or not!

Easy error to make and the trouble with these types of errors is however much you check it takes a long time for the penny to drop. Good luck next time.

[iapa]

On 19/12/2018 at 11:26, madasadad said:

Mirach is high in the sky at the minute, what would be a good second star for alignment?

Capella and Vega should both be visible, and the benefit is one int he east and one int he west

I'm at 55-51 North , so about the same as you - or close enough

[Demonperformer]

7 hours ago, iapa said:

the benefit is one int he east and one int he west

That, of course, assumes that you have clear views to both east and west and don't have houses, trees or streetlights in either direction ...