nexstar is causing hair loss

[spillage]

Hi All,

Well my nexstar 127slt is driving me around the bend.

Last night was about the 5-6 times I have tried to align this thing up properly.

1.location is Bristol and have also used exact co-ordinates.

2.date and time correct (us style date). Daylight saving on.

3. I know its not supposed to matter but the scope is level.

4. Tried skyalign, two star setup.

5. Tried mains power lead and my 7amp skywatcher power pack (fully charged).

 

Every time it all seems to go well and states that alignment has been accepted. Slew to jupiter and red dot sight goes to about 4 o'clock with a gap I can place two finger between. Slew over to Saturn and again its out by a mile. It takes a few seconds holding down the direction button to get it back on target.

I am lost as to what is going wrong and have spend an age watching youtube vids and trawling through google.

I can only hope its a user issue and not the actual scope.

Any help would really be appreciated whilst I still have some hair left.

cheers

Spill.

 

ps sorry if this is in the wrong section.

 

forgot to add nexstar+ running 5.21.2336 firmware and 5.18 mc firmware.

 

 

[Peter Drew]

Hello Spill. You seem to have done everything correctly. The only added "advice" I can think of is to check the power connection to the mount, these have given issues in the past, and make sure that the star centering for allignment is made with an UP and Right final movement each time as this reduces backlash in the gears.  Good luck.  

[spillage]

Hi Peter,

Sorry forgot to mention that bit. I tried up right and down left when aligning all the stars. I will google the power connection issue though. Could it be firmware?

Thanks,

Spill

[2STAR]

1 hour ago, spillage said:

Hi Peter,

Sorry forgot to mention that bit. I tried up right and down left when aligning all the stars. I will google the power connection issue though. Could it be firmware?

Thanks,

Spill

hi Spill, its normal for the need to hold down the buttons on slew a second or two due to backlash settle.

You do need to have the tripod level ,  a reticle eyepiece is the answer to centering the star on alignment, ( or put it out of focus to be a doughnut to center), 2 star auto align is best i find, ( you only need to know the name of one star on the particular night) make sure its not just 2 star align you have it on. I use a 20mm eyepiece reticle and it works ok the stars dont fly past so you have time to center. Make sure your red dot is aligned with your scope spot on. Alignment can be a pain i know, it needs to be accurate and I take a good time on it as everything else depends on it being accurate. I still dont get it spot on every time so switch off and try again is what i do, hope this helps.

eric

ps: when you eventually get aligned, go in the menu and find precise goto, it is far more accurate to use and easy, never fails me yet, find your obect in the list it presents, it finds the nearest star to your object, you press enter it goes to that star,adjust your focus again, press enter again and you are on the object you wish to view.  

 

[spillage]

Thanks Eric,

I will make sure it is 2 star auto align and then also go through the precise goto which I have not tried. I have also being using a 20mm ep and making a doughnut to center.

cheers

Spill.

All I need now is another clear night. :/

 

[Riemann]

1 hour ago, spillage said:

I will make sure it is 2 star auto align and then also go through the precise goto which I have not tried. I have also being using a 20mm ep and making a doughnut to center.

 

 

Hi Spill

If you not using a recticule eyepiece with a cross-hair, then 20mm is not going to be particularly accurate - it is surprisingly hard to get stars exactly centred and a long focal length eyepiece makes any error from centre worse.     You would be better off using  a higher powered eyepiece.  I think your scope comes with a 9mm but if you have a 6mm that would be even better.

If it is hard to get stars in view with the 9mm during align, then roughly centre with the 20mm then swop to the 9mm before finalising the centering of that star.

Peter

 

[spillage]

I have an 8mm ep and a 6mm on the way so once I have some clear skies I will take my time and follows the tips given and also look into setting up the backlash correctly so will keep my fingers crossed.

cheers all,

Spill.

[Louis D]

Wow, I have a 20 year old Sky Commander DSC unit on my dobs, and it's always remained dead accurate throughout the night after a non-leveled two star alignment.  Does your telescope's design use DSCs or does it rely on the accuracy of the stepping motors to figure out where it is on the sky?  If the latter, there's probably too much slop in the gear train for decent accuracy.

[cloudsweeper]

I always been OK with both my Nexstars - make absolutely sure your lat and long are spot on, with the appropriate N and W, and that the RDF is well aligned with the 'scope (by doing a test on a very clear distant object).  The two star method needs the stars correctly identified - are you dead certain they are what you think they are?

To be honest, I often just the one star method, and - as long as you aren't too far away from that star - it works fine: the target is always well in the view.  Also - solar alnmt. is accurate - so try using Jupiter.

If all else fails, you can re-flash (if that's the correct phrase) the hand controller.

Hope this helps.

Doug.

[spillage]

Just a quick update. After coming home from work I decided to have another look and found out something I think may be a bit odd.

On movement speed 3 in the alt there is a very little delay in direction change but in the alz there is over a 6 second delay in the mount moving.

Could this be causing issues or is this normal.

 

cheers

Spill.

[Peter Drew]

Yes!

[Louis D]

20 hours ago, spillage said:

Just a quick update. After coming home from work I decided to have another look and found out something I think may be a bit odd.

On movement speed 3 in the alt there is a very little delay in direction change but in the alz there is over a 6 second delay in the mount moving.

Could this be causing issues or is this normal.

 

cheers

Spill.

Gear slop as I suspected.  It's likely a gear has partially stripped on its shaft and needs replaced.  Eventually, it will just spin freely and do nothing useful at all.

[JG777]

On 06/07/2016 at 19:16, spillage said:

Just a quick update. After coming home from work I decided to have another look and found out something I think may be a bit odd.

On movement speed 3 in the alt there is a very little delay in direction change but in the alz there is over a 6 second delay in the mount moving.

Could this be causing issues or is this normal.

 

cheers

Spill.

Have you tried adjusting or dialling out the backlash from the handset settings ? 

[spillage]

I did try adjusting the backlash settings but made no difference. I think I need to wait for a clear night on the weekend so I am not feeling too rushed about setting things up. The tracking is fine once the image is centered is just the slewing to an object. I am sure its the user at fault.