Synscan 3.35... problems again

[LewisM]

Tried out 3.35 tonight, and to keep a long intro short, I just backdated to 3.28B15 again!

PAE does NOT work. It says "Centre: Fomalhaut". So, I centre Fomalhaut. Hit enter. It goes back to the main screen: Setup PAE>>. Put the scope back to polar position/park position, and try PAE again. Slews to star, asks to centre. I centre, hit enter, it goes back to PAE Setup>>. Hmmmm. Cannot do ANYTHING.

I remember 3.33 being odd when slewing, in that it would arrive on target, then slew away and back on again for several iterations before stopping and beeping OFF target. This was supposedly eliminated if you ran only a 2 star align. Well, I did a 2 star align in 3.35, and the same slewing iterations, before stopping OFF target. Tried a 3 star, and it did the same - slew iterations (about 6), then stop several degrees AWAY from target.

So, back to 3.28B15 for now. If need be, even back to 3.27, or just using EQMod instead.

Anyone else finding the same or similar quirks with 3.35?

[Camelopardalis]

I updated my EQ6 a couple weeks back and I've only got out with it 3 times so far. I can't vouch for whether or not the polar correction is accurate, other than to say my 2-star alignment the other night kept putting objects in the centre of the FOV for 6 hours the other night (before packing up).

For me, after I've picked the PA star it slews to it, I centre it, then it slews away and prompts me to make the altitude and then azimuth correction to centre the star again. As in the user guide, I the realigned.

It does dance around the target object a couple of times, seems to be worse with the 3-star alignment but I only tried that once. 2-star seemed to be doing the business.

[Merlin66]

Lewis,
When pain persists, cut your losses and go back to V3.27...

[LewisM]

Yeah Ken, been on 3.27 over a year now. 3.33 was a bust, as it seems is 3.35 for the most part (the GOTO iterations get worse east for me too). 3.27 does NONE of this, at all.

I like 3.28B15 because it lets you know your apparent PA error after alignment. I never run the PAE in 3.28 because it is as bad or worse than the recent ones. 3.28 is 3.27 just with the alignment error report after alignment.

[h0ughy]

simple - if your mount has encoders then use the 3.35 with the 2.09 update for the motors, but if you have a standard eq6 - dont bother upgrading it as it doesnt have the encoders that talk to it

other then that use EQMOD

[rmuhlack]

c'mon Lewis - surely it's time by now to at least give EQMOD a chance... :question: ;)

[LewisM]

Yeah, I have been trying it all afternoon - running the Sphinx with CGE Pro driver through ASCOM/EQMOD. Works FINE.

THe GPD2 with the Synscan GOTO system on the other hand is being a little cantankerous with it. Jittering around. Might just keep that running Synscan for now.

But, the Sphinx with the NexSXW board LOVES EQMOD. (I didn't have a hand controller for it anyway, and the Celestron NexRemote software is wanky ;) )

[Astro_Bot]

I finally loaded v3.35 to give it a try on my NEQ6 Pro - four evenings in total over a couple of weeks. The short answer? I'm back on v3.27. :rolleyes:

Here's a couple of related threads that this post would have been equally at home in:
http://www.iceinspace.com.au/forum/showthread.php?t=109561
http://www.iceinspace.com.au/forum/showthread.php?t=106489

Specifically, I noticed the same poor GoTo accuracy after 3-star alignment. Slews to the target were accurate until the final step, when the mount "jumped" off the target by around 1 degree as I watched through the Red Dot Finder. That final part of the slew was quite fast, hence me describing it as a "jump". I'm not sure what causes that.

The oddest thing about it is that the first two times I used v3.35, it seemed alright - average accuracy was a little worse than v3.27 perhaps, but not so bad. The last two times the accuracy problem became more apparent, which then caused me to look more closely hence noticing that last step "jump". The only difference between the sessions was which alignment stars I used (due to the latter two sessions being later in the evening).

I was back on v3.27 tonight for a late-evening session, but not completely without problems (and, no, I don't mean the pesky clouds that Weatherzone got completely wrong). I'd forgotten that v3.27 can be pretty sparse with its alignment star recommendations at times (v3.35 seems to have a richer database in that respect, at least that's my impression). I got 'alignment failed' after poor SynScan star selection and had to pretty much pick my own stars to get 3-star alignment success, although it got a bit better near midnight - better stars to choose from, I think. (BTW, I did around 6 3-star alignments through the session, including one complete reboot).

My summary thoughts, for what they're worth: 3-star alignment is still sensitive to which alignment stars you choose or are recommended by SynScan, so at some times (of the year/evening) star selection may be poor leading to poor GoTo accuracy or 'alignment failed'. SynScan v3.35, while not immune to star selection and general accuracy issues arising, seems to have a better database and/or star selection algortithm (I think), but has that bug of jumping off the target, which makes things worse overall.

I noticed that the database loaded with SynScan v3.35 is 3.28, while the database loaded with SunScan v3.27 is 3.27. This begs the question, what is the database loaded with SynScan v3.28? Maybe it's worth using that version purely for the updated database? :shrug:

[rustigsmed]

Hi Astro bot did you try the 2 star alignment? apparently that works better than the 3 star alignment in 3.35 :shrug:

[Astro_Bot]

No, I'm not interested in 2-star alignment. I've read others' reports of 2-star alignment apparently working OK, but I have no way to correct for "cone error" in my visual setup (10-inch SCT on Losmandy-style dovetail).

I don't think it's too much to ask for basic functions (alignment and GoTo) to actually work as intended.

BTW, my post was simply a report of my experiences, not specifically aimed at bashing SynScan.

[Astro_Bot]

Just had a thought:

Does SynScan v3.35 assume that the polar align procedure has been done, even if it hasn't? Could that be the source of GoTo errors of varying degrees and differences of opinion on performance?

I've done no experiments and collected no data on this - it's just an idle thought, but I'd be interested in what others think.

[ReaPerMan]

I found that I would do a 3 star align and the pointing was brilliant. Then I would polar align and the pointing turned to crap. 3 star align again and it was back to good again??? By definition if you have polar aligned the mount it should be on so that doesn't change but somewhere in this process it seems to frag the 3 star align data? I found that I would polar align the mount with synscan then fire up maxim and with a few tweaks it was spot on.

[LewisM]

Just do a simple drift align and ignore the Synscan routine. I find if I set up with compass to the head (on an aluminium bar to get it away from motors and iron), then do a 2 star alignment, changing any erroneous alt and az between each 2 star align by roughly the error it reports (for usually 3 iterations, if I guess the error displacement well), I can easily get it to within less than a MINUTE in both axes, and then further refine with a simple drift alignment by CCD.

I gave up on the Synscan routine a long time ago and just do it MYYYYYYYYYYYYYYYYY way.... (sorry Frankie)

[Camelopardalis]

The Synscan manual says to redo the star alignment after running the polar alignment routine.

[Steffen]

Yes, after polar alignment (which physically changes where they mount is pointing) – regardless which method is used – a new 2- or 3-star alignment is required.

Cheers
Steffen.

[Pebs4]

Hi All i hope im allowed to ask a question as well in this thread? I have a similar issue with my HEQ5 pro.
1. I roughly polar align point to south in Australia.
2. The scope is parked so i just start it off with the configuration.
3.I always do a 3 star alignment.
4 It find planets very accurately, BUT is slowly goes off course. What could that be? takes around 5 minutes and it goes out of camera view.

kind regards

David