Faulty Coordinates On EQ Mount

[Jimlau]

After I polar align with EQ mount (AZ-GTi), the slew to my first target is way off (e.g 40+ degrees), even tho mount/camera were aligned to north star after polar alignment.  Alignment is set to where Alt is my latitude and Az is 0 (and DEC = 90, RA=0). It was close to that even before polar alignment started. Any idea why? I expect it to be off, which is why u need camera alignment, but by so much?

I use EQMOD to connect and NINA.

And if successfully slew and center with plate solve, the indicated Az/Alt is still way off and not re-set to the current centered object; will NINA know to set tracking rate to the centered object, or will it track using the faulty current Az/Alt coordinates?

Thanks.

Edited September 29, 2022 by Jimlau

[malc-c]

To see if its and EQMOD problem or something else, are you able to slew to a target when using the handset?  If that the case then and the issue only happens when using the PC / EQMOD then it could be that the incorrect location data hasn't been set in EQMOD,  the PC time is incorrect or one the application is using daylight saving ontop of the PCs BST setting, or it could be (and I'm betting this is the case) that you haven't set the mount to use the custom gear settings as stated on  the EQMOD prerequisites website  

[Paul2019]

I don’t have the mount you describe and I’m very beginner myself but just going to throw it out there,

Is the date/time correct? 
Your latitude and longitude correct? 
Mount Level? 
3 point polar aligned with good accuracy? 
 

I only mention these because all of them have bit me whilst learning to use NINA and my new mount 

[Budgie1]

Another thing to do is make sure you return the mount to it's Home or Park Position at the end of a session. This way, the handset or EQMOD has a reference point to work from when you next switch it on.

I've got marks on the RA & DEC axis to indicate both the Home & Park positions, so I know it's correct when I start.

[malc-c]

On 29/09/2022 at 16:52, Jimlau said:

I use EQMOD to connect and NINA.

Thanks.

How are you making that connection? - do you use an EQDIR cable or are you connecting the computer to the mount via the synscan handset set into PC-DIRECT mode ?

[cloudnine]

Deleted my comment as I now realise you have a different mount to me. I have an AZ-EQ6 GT Pro with auxiliary encoders which need to be switched off for good pointing, I have no idea about the AZ GTi. Soz.

Edited October 1, 2022 by cloudnine
Brain fade

[Jimlau]

I connect with a hand held cable. Checked time and location. It may be an encoder issue. Will test it n a few days.

Thanks.

[LaurenceT]

Now I'm a complete newbie at all this but something just occurred to me regarding poor alignment after slewing. I have 2 EQ mounts , an AZ GTI and an EQ5.

On the EQ5 it is possible to accurately set the Equatorial Home Position using the printed numbers on the mount, it is not possible AFAIK to do this on the AZ-GTI.

I've never had any problems with alignment after slewing with the EQ5 but accuracy with the AZ-GTI is patchy to say the least.

Hopefully someone with more experience can throw some light on this.

edit: maybe this procedure is not necessary on the AZ-GTI because of the software.

Edited October 2, 2022 by LaurenceT

[malc-c]

7 hours ago, Jimlau said:

I connect with a hand held cable. Checked time and location. It may be an encoder issue. Will test it n a few days.

Thanks.

 

On 29/09/2022 at 16:52, Jimlau said:

After I polar align with EQ mount (AZ-GTi), the slew to my first target is way off (e.g 40+ degrees), even tho mount/camera were aligned to north star after polar alignment.  Alignment is set to where Alt is my latitude and Az is 0 (and DEC = 90, RA=0). It was close to that even before polar alignment started. Any idea why? I expect it to be off, which is why u need camera alignment, but by so much?

I use EQMOD to connect and NINA.

If the mount is an EQ mount, you state that both ALT and latitude is 0.  Unless you are at the Equator your latitude will be different to match the same latitude as your location, which if in the UK is around 54 degrees.

You say you use the "hand cable" I presume you mean a handset, yet you state you use EQMOD and NINA.   You can't use both.  If the handset is the same as most SW EQ mounts you can't have it perform the alignment and then start using EQMOD.  I also asked how are you connecting a computer, is it using an EQDIR cable?   If you can post a picture of how you have the scope set up and state where you are based it will help us second guessing.

Can you also confirm that you have entered the custom gear settings for the AZ-GTi as stated in my previous post with the link to the EQMOD page ? - Without doing so the mount will be way off target as it will assume you are using an HEQ5 or EQ6 mount which have totally different gear ratios

Unless you are using the mount in an observatory where it doesn't get moved, EQMOD assumes you are starting from the default home position, which is weights down, RA axis pointing at the NCP with the DEC axis parallel to it.  You can then use whatever aquarium program to select a target, which if needs correcting is done through the NSWE buttons on the EQMOD interface on screen.  Then once centred you Sync the target via the planetarium program (I don't use NINA so can't advise on that aspect).  If you repeat this for stars in the west, and east  EQMOD should then work out the corrections and any target inside those points should be more or less centred on subsequent gotos.