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Phillips6549

Setting up a SW EQ3 Pro with Synscan

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Complete beginner question regarding using this mount.

When I have tried to set up and align the mount , the goto targeting is off by many degrees.  Here's what I do - can someone tell me what I'm doing wrong!?

 

With the power off:

Align the tripod and mount to North and, with the clutches released, set the declination to my latitude (52deg 28' N). and the mount in the weights-down home position.

Lock the clutches and fine tune the alignment on Polaris using the mechanical adjustments on the mount.

 

Turn the power on:

Set up the date, time and location, elevation etc. in the handset (noting the American Date format and Longitude first (set to W 1deg 48')

DST = Yes

Select 1 Star align

Pick a star, I usually try Procyon or Betelguese depending on the time.

The scope slews to vaguely the right direction but actually nowhere near.  It can take 2 or 3 minutes of manual slewing to centre the star in the eyepiece.  Finishing, of course, with an up and right movement.

Finally, press Enter to complete the alignment ==> Alignment Successful says the handset optimistically.  

Now from the object menu pick another target.  Try, say, Polaris which was where I started and ... nowhere near it.   It's the same regardless of the selected target.

 

I have tried 2 star alignment and 3 star alignment, a factory reset before starting,  but nothing seems to work.   Once i'm lined up on a target the mount tracks nicely - it just won't go where I want it to!

Not yet at my wits end but - Help!  :BangHead:

Mark

Edited by Phillips6549

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The error would appear to be in your initial mount alignment. First Adjust the altitude of the mount to your local latitude with the adjustment bolts. Then align the mounts RA axis with the North Star (roughly) with the weights in a downward direction. Only then attachthe telescope tube and with the clutches released align it with the North Star (roughly). Fasten the clutches.  Do a 2 star alignment using stars both sides of the meridian.

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42 minutes ago, Phillips6549 said:

Align the tripod and mount to North and, with the clutches released, set the declination to my latitude (52deg 28' N)

I assume you are setting the axis of the mount using the two latitude bolts & the 0-90 degree scale on the side of the casting. Worth double checking, this scale is easy to mis-read, could easily be a couple of degrees out.

47 minutes ago, Phillips6549 said:

the goto targeting is off by many degrees

How many degrees is the error? (Estimate , little finger = 1 deg, fist = 10 deg). Is it RA or DEC or a mixture?

Is the error repeatable? Repeatable errors point to settings. Completely random errors indicate power supply problems.

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Thanks for the replies

The error is a few fingers of,  not quite a fist.  Always seems to stop up and to the right of the target.  I set the declination using an inclinometer, the scale on the mount is not really much use.  I'm using a fully charged power tank to supply the mount.  

I'll be going out again I  a little while and will try the initial alignment with the tube removed. 

Mark. 

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Last night was better, but still off by 2 fingers ✌️ up and to the right.

It must still be my initial alignment of the mount axes.  Looking clear again tonight so I'll have another go!

Mark

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Success!  ?

Last night I spent a bit more time carefully aligning the mount then the OTA and doing a 2 star alignment and... it WORKED!   The next target selected was bang in the centre of the viewfinder.  A great evenings viewing followed, only marred by the full moon and general LP washing out the sky.  Hoping for some clear weather in a couple of weeks with only the LP to contend with. 

 

Thanks for the advice,  hopefully now I know what I need to do it'll get faster. 

Mark. 

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