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Noreik

Synscan Problems with Skywatcher Star Discovery 150P

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Hello all,

I have recently got one of the above telescopes for Christmas and I'm really excited about finally having a proper telescope BUT the Synscan does not seem to be working correctly.  If I can just list below the steps I have used:

1. Set up the tripod, using a spirit level to ensure it is level.
2. Attach the OTA.
3. Turn on system and enter the relevant information - Long first, around 0 degrees West and the Lat, around 52 degrees  North; time and date; +0 for time zone and no to daylight saving
4. Choose alignment method - at this point, Skyscan usually suggests Altair, Vega or Deneb for Brightest Star Alignment, none of which I am confident in finding (and don't believe the location information on the handset - more about that shortly) so I usually try 2 star alignment.  Tonight, I chose Alioth as the first star and then Capella as the second star.
5. I manually moved the tube in the right direction (I mention manually just in case this is wrong, but I did also start from 0 altitude and then use the motor subsequent and got similar results) and then centered in scope using the 25mm and then the 10mm eyepieces.  
6. I confirmed that Alioth was centered in eyepiece and then the scope slewed to Capella, only it was nowhere near Capella - only 23 degrees of so of altitude whereas it is much higher (Stellarium confirms that Capella is at 82 degrees of altitude at the time of night - 9pmish - that I was looking).
7. Not to be disheartened, I used the motor to move Capella into the center of the scope, first with the 25mm and then the 10mm.
8. Alignment complete came up.
9. It did say something about NLE or NPE, which I'm not sure what it meant.
10. I tested the alignment by asking it to find Dubhe and the aligned itself roughly halfway between The Plough and Gemini.
11.  I started again, this time starting with Capella as the first star and the results were even worse!
Is there anything I'm doing wrong?
If it isn't me, then I'm thinking I may as well have a larger Dobsonian mount scope or an EQ Refractor at a reduced price (my budget is c.£400).  If I do need to return the scope, what would people suggest in place - probably going to be more into visual astronomy that astrophotography?
Thanks,
Noreik

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Two things I would mention.

1) the Synscan date format is mm/dd/yyyy. Be aware of this. So today is 01/10/2016

2) I'm not totally familiar with your mount but I'm guessing it is an alt Az set up so similar to my SW Synscan Dob. If so, during a two star alignment I use the slew keys to move the scope to the first star, not manually.

Edited by Owmuchonomy

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Chris - you may have solved it!  I'm pretty sure I put in dd/mm/yyyy.

Will try it again the next gap in the clouds and will use the slew keys.

Does it matter where the scope starts from?  I.e. do I need to point it north and at 0 degrees altitude?

Thanks,

Noreik

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Chris - you may have solved it!  I'm pretty sure I put in dd/mm/yyyy.  In fact, I've just looked at Stellarium for the date I was inadvertently entering and it makes perfect sense for the mount to be telling me to focus on the stars it did.

Will try it again the next gap in the clouds and will use the slew keys.

Does it matter where the scope starts from?  I.e. do I need to point it north and at 0 degrees altitude?

Thanks,

Noreik

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I have a v. 3 SW alt Az Synscan system on my Dob. For that it is necessary to level the scope parallel to the ground ('0') and line it up due North (true) before doing anything else.

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Chris - you may have solved it!  I'm pretty sure I put in dd/mm/yyyy.

Will try it again the next gap in the clouds and will use the slew keys.

Does it matter where the scope starts from?  I.e. do I need to point it north and at 0 degrees altitude?

Thanks,

Noreik

It shouldn't matter where the mount starts from the handset starts the alingment routine once the first star has been centred. The alt as goto mounts required this is the past but it now not needed.

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I have this scope and always use brightest star. I use Google sky on my phone to confirm which star is which, just make sure the 2 stars are as far apart as possible this is where Google sky helps you choose. Once aligned its been spot on.

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Hope you are using a decent power supply and not the AA battery pack! Well done on your analysis of the setup problem and clear skies (whatever they are!!).

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Hello all and thanks for the kind words.

Out again tonight to try using the correct date and straight away I was encouraged to see names of stars come up that I could actually see and were not below or on the horizon.  Brightest star again did not seem to work, so I tried 2 star alignment with Betelgeuse and Alioth (as I read somewhere to try and select stars greater than 60 degrees apart for greater accuracy).  The scope slewed round to Alioth on the edge of the 25mm lens so made some quick adjustments and thought I was sorted.  Asked the scope to view Saiph to check the alignment (I also figured that if it 'knew' where Betelgeuse was then a star in the same constellation should be a doddle) and it was quite a considerable way out as in the width of Orion away from Rigel even.  The altitude seemed right, but the Azimuth was what was way off.

On the bright side, I did manage to see my first galaxy, the Orion Nebula, by using the direction keys to align...but I sort of wanted Synscan to do that for me 'cause that what I paid for!

The only thing I can think of that I'm doing wrong is not polar aligning (but my understanding is that isn't necessary with this sort of mount) and/or I'm using rechargable AA batteries (which I charged two nights ago).  I would consider getting a powertank, but not until I have the Synscan system working!

Can anyone else suggest anything I'm doing wrong?

Thanks in advance,

Noreik

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Hello all and thanks for the kind words.

Out again tonight to try using the correct date and straight away I was encouraged to see names of stars come up that I could actually see and were not below or on the horizon.  Brightest star again did not seem to work, so I tried 2 star alignment with Betelgeuse and Alioth (as I read somewhere to try and select stars greater than 60 degrees apart for greater accuracy).  The scope slewed round to Alioth on the edge of the 25mm lens so made some quick adjustments and thought I was sorted.  Asked the scope to view Saiph to check the alignment (I also figured that if it 'knew' where Betelgeuse was then a star in the same constellation should be a doddle) and it was quite a considerable way out as in the width of Orion away from Rigel even.  The altitude seemed right, but the Azimuth was what was way off.

On the bright side, I did manage to see my first galaxy, the Orion Nebula, by using the direction keys to align...but I sort of wanted Synscan to do that for me 'cause that what I paid for!

The only thing I can think of that I'm doing wrong is not polar aligning (but my understanding is that isn't necessary with this sort of mount) and/or I'm using rechargable AA batteries (which I charged two nights ago).  I would consider getting a powertank, but not until I have the Synscan system working!

Can anyone else suggest anything I'm doing wrong?

Thanks in advance,

Noreik

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You shouldn't need to polar align a GOTO Alt-Az mount. Rechargeable batteries usually deliver 1.2V. Your mount needs 12V to operate correctly. If you are using the supplied battery holder, then you will only have 8 x 1.2V = 9.6V. The electronics will struggle with that.

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I have just got this scope aswell but not had a chance to try it out yet (damm clouds!!) but hopefully will get a chance in the next couple days and will let you know if I spot anything similar with mine.

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Hi, I take it your red dot finder is aligned ok? It's possible to mistake a star this way. Also as others have mentioned try using a mains fed power source.

Hope you get this resolved.

Cheers,

Steve

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Hi, I take it your red dot finder is aligned ok? It's possible to mistake a star this way. Also as others have mentioned try using a mains fed power source.

Hope you get this resolved.

Cheers,

Steve

If you're using a mains power supply. Make sure it's a protected/smooth output. Last thing you want is power surge taking out the Synscan. That's why I run mine from a 12v battery supply.

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Tried again tonight with alkaline batteries (I don't want to pay out for a battery pack if I can't get this working) and tried both methods of aligning but without success.  The two-star alignment method was about 45 degrees further east than it should have been when I asked it to slew to Alderbaran to check the alignment, so I don't think the red dot could have caused that.  I've double-checked I've got the names of the stars correct on Stellarium before and after going out too.

Can anyone suggest anything else?  I feel thoroughly disheartened as I can't even align a GOTO scope correctly so actually finding anything worth looking at may well be beyond me :(

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Sorry to go on about batteries - are you certain that the alkaline batteries you used were all new? I used the AA battery pack with my first scope and quickly realised it was a complete waste of time. Unless you can guarantee at least 11V or so, the electronics gets upset. This results in inaccurate target location, etc.

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I just tried my one out tonight and all seemed fine. The only thing I think I would ask is when you are doing your alignment and you have selected your second star the scope slews round to said star, from what I understand this is where you are having problems? you should get  message come up on the handset saying 'centre to eyepiece' or similar, at this point are you able to adjust the scope with the handset or is your only option to press 'enter'?

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Hi Popeye,

Once it slews round to second star, it is always off - usually azimuth rather than altitude - so after changing the rate of slew up to about 8, I centre to finderscope first, then to 25mm eyepiece and then to 10mm eyepiece and then I press enter.  Alignment successful is displayed, followed by something about previous NP values being applied or something similar - I have no idea what this is - and then I test it by pointing at another star and it's miles off, again, usually azimuth rather than altitude.  Then I post another message on the forums!

Mikea - I think I remember checking the voltage when using the rechargables and it came up as 9.6V as you said, so I will check again with the batteries I'm currently using to confirm that it read 12V. 

The only other thing I can think of is can anyone in Northampton swap 30 minutes of their time for selection of drinks of their choice?  Easy on the methuselahs of Dom Perignon though!

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Update - checked the voltage for the mount, which says 11.4V - is this sufficient?

Also, after aligning the handset says something about 'caution previous NP or NL values applied' - does anyone know what this might refer to as it had FLO stumped?!

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Hi mate,

I am a complete noob myself when it comes to this stuff.

However I have just read your post and it seems like you are having the same issues as I was last night. I setup up my mount and scope last night and everything was way off! Similar to yourself! So I ended the night in frustration.

I have come back to it today and checked over a few things. The first issue was the telescope was mounted the wrong way around!! Turned it 180deg to fix that.

Then I checked the settings in Synscan and found I had entered my Lat and Long in the wrong order.

I have now done a rough polar alignment indoors, a 2 star alignment then told synscan to point to the moon and hey presto it was near as damn [removed word] on!!

Schoolboy errors or what!

Thought I would share anyways, maybe you could double check your settings.

Hope you get it sorted pal...

Gaz

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Also had the NPE error but I just ignored it and it worked today.

Las night it would not let me go any further......

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Sounds to me like either a lat, long issue or more likely a time issue. Are you getting The daylight saving time correct? Currently it's no. The handset should show the local time to confirm.

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only other thing I can suggest is that if you are sure you have put the lat lonng in the correct way then check that it is in the correct format-a position can be displayed severl diffent ways-the skyscan eems to prefer the 'degrees decimal minutes' format

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Just been for my nightly exercise in futility...2nd star was in the right section of sky (i.e. I could see what it was trying to do) but still needed significant adjustment as was outside the FOV of the lens, completely defeating the object of the GOTO aspect!

After starting again for the 5th time this evening and aligning using 2 star, with the second star being Dubhe and the first being Sirius, I then asked to see Dubhe...the star that I'd just told the mount it was pointing at...and it slewed anti-clockwise about 10 degrees and down about 2!  Surely that can't be me being thick?!

Anyway, I'm sick of it now so I'm going to ask to change it for an 8" Dobsonian so that the money I spend will actually improve the experience rather than frustrating me.

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