Synguider Issues - Help Please :)

[StephenK]

I have spent a few nights out withthe Synguider and I just cantget it working right. Perhaps someone on here has the answer for me

I have a HEQ5 Pro, 80ED with a Canon 1000D. Stratravel 80 with a Synguider.

The Synguider is focused correctly, lined up so that the hand control moves the star in line with one of the axis, I lock on a star, do Autocal, and as soon as it starts guiding, the star just flies off the bottom of the screen. Time and time again.

I even halved the RA/DEC aggressiveness, as has been suggested in a number of threads, bu to no avail.

HEQ5 is set to 0.5x for guiding.

Has anyone had a fix for this, as I have seen a few others with the same issue.

I gave up in frustration,and just did a pile of 2 min subs on Polar Alignment.

Help!!!

Thanks.

[keiserx]

hi Stephen,

i've got exactly the same problem with same equipement... (Heq-5 + Sg + 80ED + ST80)

Heq5 speed 0.5x, Sunguider focused, corect axis, star lock, autocal, and when guiding the first five minutes are ok first shoots are good, and then the guiding star move up slowly , each times...

Do you solves this problem ?

Julien

[primordial atom]

Hi guys,

HEQ5 me too

If you've locked a star I can't really understand that, how long does it take to drift off the screen? you describe it as flying off.

However you could try making  sure you're not guiding to a hot pixel in the chip, I fell for that and nearly gave up on it, I now have it guiding really well for 10 mins and longer.

Is it doing the auto cal routine correctly?

When it says guiding the bottom 2 lines of info on the screen should be showing the occasional +/- 1 or 2 at the maximum, and the mount should be making some happy chirping sounds as it is guided.

Have a look at this by Dion on the Astronomy Shed and go thro it thoroughly  http://www.astronomyshed.co.uk/forum/viewtopic.php?f=34&t=3949&hilit=synguider and try again and post your findings.

Don't give up on the synguider as others have done , they DO work well, we'll sort it

[jambouk]

I've been thinking about a synguider but the majority of the opinion i seek suggests don't do it, though despite that i'm still heavily drawn to that stand alone idea, so i'm watching this thread with interest.

So i have no experience at all with this, but is the mount reasonably well polar aligned in the first instance? If not, i suspect the sunguider will struggle [fail] to guide. Just a thought.

I hope you both get it sorted.

James

[Steve Ward]

I've had one for a couple of years now and have no problem getting 20 + minute subs from it , have pushed it to 40 in testing with no issues . 

As James suggested , you need to be well PA'd first , the better the alignment the less work the Synguider has to do , I drift-align personally.

[primordial atom]

Opinions on the Synguider are very divided, it's a true love it or hate it thing and I don't know why. It takes a bit of patience and I would have loved to have had it demonstrated to me , as lots of aspects of Astro, would save a lot of heartache . PA is another source of frustration for beginners, I might set up a demonstration work shop for such things .

[AndyUK]

I haven't had a Synguider for quite some while now... but I STILL have a soft spot for it.  I only really changed for two reasons, the first of which was that the original reason for buying it was because I didn't ever see myself using a laptop for guiding/capture (I now have a CCD camera, so that blew that!) and the second reason was that if it loses the guidestar, and you're not watching it, then it won't re-acquire again or even bleep at you - It just displays a message on the back of the screen (which wasn't good for me as I like to doze for 60-90 mins at a time, otherwise I'd be useless at work the following day!). 

But those reasons aside, for being in the field with a DSLR, then I still think they're a very good solution if you don't want to be constrained to using a laptop - I used to default to 10min exposures when using the DSLR (ocassionally using 15 mins in the winter), but in testing did get up to 25mins with little issue (other than rotation due to poor PA!)

From what you're describing, I would have to agree with David that you may be trying to guide on a hot pixel...  Maybe you could test this by pointing scope/Synguider at (say) a named star and seeing what that looks like on the Synguider and maybe then you'll be able to pick out where the hot pixels are?  For me the biggest secret to getting the Synguider to work was getting the focus right (again, I used to use a named star).  Once you've got the focus sussed on a really bright star, (which may require reducing the exposure down to something silly like 32ms and then tweaking the focus to get the highest brightness value), you can then move to your DSO and set the exposure to the full 4096ms and see what stars are in the field.  If you use the handset to move the mount a tiny amount, you should see the stars move (to differentiate them from any hot pixels)

I remember for me there was a temptation to reduce the exposure to ridiculously low values, but I later preferred to guide at either 2048 or 4096ms if I could, but again, it's important not to guide on TOO bright a star (although sometimes I was forced to do so in order to get a low enough brightness setting...)

[Astroblagger]

i had one for a while and just didnt get on with it, it seemed hit and miss, im pretty sure the focus was spot on, i got fed up with it and sold it and got a finder guider which i use with PHD and havent looked back, Finder guider is light also so doesnt add too much weight to your overall setup, as Andy was saying i rebelled against using a laptop at first, but when i started using the  finder guider and phd and using APT with all its useful functions i couldn't think of imaging without a laptop now. 

[lensman57]

I have spent a few nights out withthe Synguider and I just cantget it working right. Perhaps someone on here has the answer for me

I have a HEQ5 Pro, 80ED with a Canon 1000D. Stratravel 80 with a Synguider.

The Synguider is focused correctly, lined up so that the hand control moves the star in line with one of the axis, I lock on a star, do Autocal, and as soon as it starts guiding, the star just flies off the bottom of the screen. Time and time again.

I even halved the RA/DEC aggressiveness, as has been suggested in a number of threads, bu to no avail.

HEQ5 is set to 0.5x for guiding.

Has anyone had a fix for this, as I have seen a few others with the same issue.

I gave up in frustration,and just did a pile of 2 min subs on Polar Alignment.

Help!!!

Thanks.

Hi,

If you  have managed 2 minutes subs unguided then your polar alignment is very good so there are no issues there, if the star is probably locked and there is drift then the most likely cause is differential flexure in your guide set up, have a good look at the way the guide scope is mounted and examine the integrity of the tube rings and the set up including the rubbish draw tube and the focuser mechanism of the ST80, the wiring loom, and the way the SynGuider is coupled to the focuser. It maynot be the answer in your but in most cases of bad guiding is the most likely cause.

A.G

[primordial atom]

the only time I experience the star flying off the screen is when I've done a meridian flip and not redone the auto cal routine, when it's recalibrated again i'm off and guiding again.   If skywatcher had just done something a bit different with the instructions or operating routine I think more people would have been happy with them.

[ollypenrice]

This business of 'flying off the screen' doesn't sound like the usual stuff that afflicts guiding. I don't use a Synguider but I've seen the guide star fly off the screen often enough with all the systems I've used. There are two causes;

1) Bird brain that I am, I have failed to switch the Takahashi handset for the EM200 mount to guide speed and away from high speed.  OK, you are not using a Tak mount but maybe the mount is not really set to 0.5x siderreal. Maybe it just says it is, but you know what IT gadgets are like. Have you tried a lower guide speed? Are you dead sure that you've applied the 0.5x speed by whatever means the handset requires? I can't remember what that is off hand.

2) The guide commands are inverted so instead of getting a command for Dec positive it gets one for Dec negative, then another, and another and off the screen it goes. PHD (does the Synguider use this as its in-house programme?) detects the direction reliably for me. Astro Art, which I actually prefer, does not and needs the guide direction manually converting.

However it's arising, I strongly suspect that you have a problem either with guide speed or guide direction and this may be a bug in your electronics and no fault of your own. It might also explain why the standalones get such a mixed press, working for some and not for others. Just a thought, but the 'ST4 cables' (in parenthesis because the original ST4 cable from SBIG was nothing like the ones now called ST4) are not phone cables, though they look like them. I believe the plugs are reverse wired.

To my mind there are too many of these Synguider failures being reported for there not to be a problem somewhere. Surely it's reasonable to say, some work and some don't? I remain convinced that most of the 'convenience products' in astronomy are more trouble than they're worth. I've found I do best when I go for the slightly more complex solution and get slightly more control along with more flexibility in terms of the software or hardware. I'll stick to a netbook (very small), a good guide camera and a choice of software, Asto Art or PHD. The bit of genius in AA is the scattergraph which builds up a picture of the guide hit positions over the whole night. You can see at a glance if you've so much as one bad hit in the night. If you haven't you know all your subs will be guide error free. All guide software should have this.

Hope you sort it.

Olly

[Alan-2029]

On 04/09/2013 at 21:34, StephenK said:

I have spent a few nights out withthe Synguider and I just cantget it working right. Perhaps someone on here has the answer for me

I have a HEQ5 Pro, 80ED with a Canon 1000D. Stratravel 80 with a Synguider.

The Synguider is focused correctly, lined up so that the hand control moves the star in line with one of the axis, I lock on a star, do Autocal, and as soon as it starts guiding, the star just flies off the bottom of the screen. Time and time again.

I even halved the RA/DEC aggressiveness, as has been suggested in a number of threads, bu to no avail.

HEQ5 is set to 0.5x for guiding.

Has anyone had a fix for this, as I have seen a few others with the same issue.

I gave up in frustration,and just did a pile of 2 min subs on Polar Alignment.

Help!!!

Thanks.

Why do you guide 0.5x on Heq5? I also had problem guiding, my stars look like crosses, like ra and dec corrections are too agressive. I tried to reduce these agressiveness on up/down and left/right buttons on controller but no change. Does anyone has some idea how to fix this?

Edited February 25, 2020 by Alan-2029