SynScan polar alignment gone screwy

[HunterGeo]

Hi all,

I recently bought a new SynScan hand controller (as my old one was pre-v3 firmware so I couldn't upgrade it or control it through my computer), and I updated the firmware on the new controller to the latest version (v3.32) as a friend of mine had done so recently and recommended the new Polar Alignment procedure available in the Setup>Alignment menu.

My friend and I are using HEQ5 Pro mounts and the same version firmware on the SynScan controller... so you'd think they'd behave identically. :shrug:

The new Polar Alignment procedure (for those who haven't seen it yet) is designed to tell you how far off (in elevation and azimuth) your polar alignment is. The idea is you do a three-star alignment first, then the mount is pointed at a reference star, you then move it using the hand controller so that it is centered in the eyepiece properly, then the mount moves in Az/Elev. by the margin of error previously calculated. You're then supposed to use the elevation and azimuth knobs to manually re-centre the mount on the reference star, thereby making the polar alignment error = zero.

Unfortunately, it seems that my mount is miscalculating the polar alignment...

e.g. if it's 1deg off in Az., then when you re-centre the star, it becomes 2deg off in Az. Same in elevation. (It should actually be zero deg off as I move the mount manually to compensate and eliminate that error).

Ergo, I cannot achieve a polar alignment. When I re-try, it of course then says I'm 2deg off, and so I move another 2deg to make it now 4deg out!

Has anyone else noticed this issue?


Cheers,
Dave

[Visionoz]

See here, may be the same cause!: http://www.iceinspace.com.au/forum/showthread.php?t=101398

HTH
Cheers
Bill

[MrB]

Yes the v3.32 firmware has known issues for southern hemisphere users.
Synta are apparently working on a fix but I really struggle to understand why it is taking so long given the alignment feature worked in an earlier version.
I rarely use the hand controller now anyway.
EQMOD (http://eq-mod.sourceforge.net/) makes life so much easier for me.

[HunterGeo]

Bugger. Thanks for the advice, Bill and Simon.

Bill - I read in that thread you linked to about another issue I found last night. Hopefully it will be fixed in a firmware update.

http://www.iceinspace.com.au/forum/showpost.php?p=931534&postcount=9

This comment relates to how the mount moves back-and-forth ever-so-slightly when slewing to an object, ultimately failing to slew accurately.


Thanks again.

[Visionoz]

No Probs David

I did have to reflash my firmware back to ver3.27 after I experienced the back-and-forth motions when using the later updated versions of the firmware - will await for the "Synta fix" if that ever is going to happen!:shrug:

Cheers
Bill

[HunterGeo]

A friend of mine gave me this work-around to the problem, in case anyone is wondering....

Do a regular 2-star alignment, then move the alt/az axes manually based on the errors reported at the end of the 2-star alignment procedure (i.e. DO NOT go through the Polar Alignment menu option at all). Just move the axes as much as needed, then repeat the 2-star alignment and keep repeating until PA is acceptable. Then do a 3-star alignment to remove cone error.

It's a bit more abstract and arbitrary without a reference star to work with, but it gets the job done. I was about to get within 10arc-mins of SCP alignment in half an hour last night, and should be able to get more precise and faster with more practice (the trick is knowing how many turns of the bolts = how many degrees!).

[Poita]

So how many turns do equal how many degrees :)

What is the latest version currently?