Trouble with goto

[Liz]

Have bought a gorgeous little Skywatcher mak-cass 127AZ with SynScan goto, but cant seem to get the goto going.
Have never had a goto, so pretty sure its just me, Dobs are soooo easy. :help:
Finally a break in the weather last night so gave it another go, but it goes in the wrong direction, again, after I have aligned the first star. :sadeyes:
Have it facing south, set up the right time/date/lat/long etc .... align stars .... slew to Vega and enter, then to Altair (last week I tried Arcturus and it went in opp direction) and it heads south!! Doh.
Anyone have any ideas of what I could be doing wrong??
Have checked and rechecked lat/long and am East and South. :shrug:
I can take it to one of our club members to help me, but thought i would do a quick ask here. ;)
Thanks. :rolleyes:

[renormalised]

Bring it around my place, Liz and I'll have a look at it:)

Bring your manual with you too.

Although, if you've aligned it with the SCP, it will takes its queue off the SCP.

You may need to do a two star align to get it working properly.

[GeoffW1]

Hi,

With my Synscan, it has to be aligned quite well first on the SCP before starting star alignment. I found it best to use a compass, in conjunction with the scale for latitude setting. It also means you need to get it pretty well levelled too. It seems to be a critical thing.

Initially I also found it helpful to do first a one-star alignment, then slew back to home position, then a 2-star, and slew back to home, then a 3-star. That seemed to progressively improve the pointing.

At first, only after all that folderol would it say "alignment successful". Now I'm getting more practised and I can cut out the 2-star step.

Even then, in use, if the go-to has slewed a long way round to some object, the pointing is much improved if I re-align on a nearby star in that region.

Cheers

[Liz]

No worries, thanks Carl, will email you. :)

[Liz]

Thanks Geoff .... after the one star alignment, you say to slew back to home position. I didnt do that, I just went from Vega onto another star to do 2 star alignment.
So I go back to the SCP then do another star??

[renormalised]

Okie dokie:):)

[GeoffW1]

Hi,

Yes, this was in the phase where my SCP alignment had not been very good at all. There was actually a tree in the way in my backyard (my neighbour has obligingly cut it down now :)), and I hadn't yet realised how badly I was doing the initial setup.

So I would do a one-star alignment, then use Utility Func -Park, then turn off the hand control. This causes the Park position to be saved as a new Home. I would then turn on again and repeat that procedure for a 2-star alignment, starting from the previous Park - Home without moving anything in between. After the 2-star alignment I would slew to Park again and turn it off then on once more, figuring that I was improving the Home position each time.

I'd emphasise here that this was while I was still struggling with it, and it might all not be really necessary if you can get a really good alignment on the SCP first up.

Now with care setting on to the SCP I can always go from a one-star to a 3-star alignment without trouble, and sometimes a 3-star alignment alone is successful.

I think the next step might be to assess the accuracy of the altitude scale for latitude setting (I have a EQ5 mount) as I have read that it can be pretty rough.

Cheers

[Benno85]

I had the same issue with an EQ6 altitude scale. Thing was out by a couple of degrees so I got a protractor and hung a length of thin braided fishing line (with a weight at the end of it) through the centre of the protractor. Hold it parallel to your counterweight shaft then slowly adjust the altitude knob on the mount until the fishing line indicates the correct altitude. It's a bit rough but I found it better than relying solely on the markings on the mount.


P.S. Liz my apologies if this was a slight hijacking of your thread :thanx:


Cheers,

Ben :)

[GeoffW1]

Sounds good, I'll try it.

Cheers

[bmitchell82]

just a thought make sure its set for Southern hemisphere (South and East) (not north and west) you can have the same lat and long in northern as you can in southern. :D as long as your within 10 odd degrees your mount should do a successful align. well mine does anyhow, not saying that itll track well because it wont :D

[bartman]

Liz, not sure if this might help, but when I got my Neq6 I duly put it all together and found that the scope was going the wrong way just like you described ( inside the house just roughly aligned just to see it work). Almost crashed the scope into the tripod!.
Anyway i figured that the little do-hicky (square pin)that sits atop of the tripod and aligns the base of the mount to the base of the tripod was in the northern hemisphere posi! So I swapped it around and presto! All fixed.
Hope that helps....
Bartman

[Liz]

Definitely on south and west Brendan, but checked again anyway.:rolleyes:



I reckon you are on the right track Bart, and have just raced out to scope to check for the little nut thingo that connects mount to tripod, but cant seem to find anything noting southern hemisphere?? Bugger.
Might be something in handset too, cos I reckon thats where it thinks I am. :question:

Went through all the details of the setup again, and again ...... pressed the utility function on the handset, as tells you what you location is, and it has me at +70!!! Help, get me outa N.Hem.

[bartman]

this pic might help?
Bartman

[Jutscher]

Hey,
I had a similar problem when starting out with my NEQ6, the mount tried to track to stars below the horizon despite having been fairly certain that the mount was pointed south (i.e the bolt in bartmans pic was facing south). The problem it seems is that I was rushing through setup and didnt notice the fact that the NEQ6 uses that annoying MM/DD/YY date setup... whoops.
With that solved the scope pointed in the general direction of the alignment stars but needed to much correction to gain success.

As I couldnt see the SCP from my house due to some trees, I found the easy way for a ballpark 3 star alignment was to choose the first star (i.e. Alpha cen) allow it to slew and then rather than using the handcontroller to adjust, I would adjust the alt/az as if you were polar allinging on alpha cen. From there you could select the next two known stars and adjust with the hand controller as per normal.

This simple setup is not any good for anything but visual use but will give you a fairly accurate visual tour.

hope it helps get you started

[mithrandir]

West? South and East!

According to the National Gazetteer of Australia:


SOUTH TOWNSVILLE QLD Town or Locality 19° 15'S 146° 49'E
TOWNSVILLE QLD Town or Locality 19° 15'S 146° 49'E
TOWNSVILLE QLD Building 19° 15'S 146° 48'E
TOWNSVILLE CITY QLD Town or Locality 19° 15'S 146° 48'E
TOWNSVILLE TOWN COMMON
CONSERVATION PARK QLD Park or Reserve 19° 12'S 146° 44'E
TOWNSVILLE WEST QLD Building 19° 16'S 146° 47'E

[marki]

I think you will find the date and or time are entered incorrectly e.g. dd/mm/yy instead of mm/dd/yy. Time needs to be entered on the 24hour clock. These mounts can be a mile off the SCP and will still align and point accurately ( I know I tested mine to see how far I could be out and still have it function, 10 degrees no problem). Use the 3 star alignment as it compensates for cone error and you do not need to stuff around getting your scope right.


Mark

[Liz]

Thanks for replies Mark, Andrew, Sam and Bart.

Went around to a club members house last night, and trying to align through the clouds. No luck, so have left the scope there for him to play with.

Mark - yes, time and date were right ... yday ... 9/30/2010
Andrew - oops, no, coordinates were right at east and south, definitely.:thumbsup:

Am sure Dave will sort it out, and who knows, perhaps I have inserted some wrong number. ;)

[GeoffW1]

Hi Mark,

Mostly, that's easy enough to check. There are though a few cases around where more persistent trouble does occur.

For instance I had all that above dead right, after checking and re-checking, and I still HAD to get somewhere reasonably close to the SCP to begin, not a mile off, certainly. So it did not seem that way to me, after one time trying for 4 hours to get a successful alignment, and solving it only in the way I described earlier.

Perhaps it can be attributed to the mount I have, I don't know.

Cheers

[Strawb]

Folks,

I can definitely confirm that Liz has setup the scope correctly as far as lat/long , time and date are concerned. I have a little experience with gotos as I have a cpc C9.25 myself and he's a beaut.

I have endeavoured to make sense of this scope for two days now and I really believe that there is a software issue. For instance; if carrying out a two star alignment using Alpha Cent as the first star then one would expect that if Hadar was chosen as the second star that the scope would at least move to the right - just a little but this one drives to what I think is 180 deg out around to the Nor West !
I have parked the scope and it does this at 000 deg alt and azimuth. OK so I line up on Celestial north ( close as I can) and try again to slew to 155 deg 40 deg alt where the scope says Alpha Cent is right now. This reading is in the handset and agrees with stellarium pretty well. Ok so nicely setup on Alpha and then select Canopus which according to Stellarium is displaced further around to the southwest and whoa off we go to the north east. I confess I am lost as to why this is. The thing seems to know where the first star is Ok but thereafter .......:screwy:

Tried uploading new firmware but no joy with my usb/serial adapters on this thing.
Anyway I dont know what else to try so any more thoughts appreciated

[DavidU]

I have read that it must have longitude put in first (to 4 digits only) than latitude.

[Visionoz]

Perhaps try resetting the handcontroller to "factory defaults" - in fact after a firmware upgrade it's always a good idea to do so, IMHO

HTH
Cheers
Bill

[Strawb]

Nope - no joy after factory reset and Longitude requires all 5 characters to be inserted in order to continue the setup.Thing I cant understand is that the thing knows where the first star is - the alt/az info on the handset is correct - just the second star is way off:question:

[Liz]

Fingers crossed that it will get a new lease of life when the firmware is updated, see ya about 6.15 Dave, and thank you. :thumbsup:

[DavidU]

SynScan(TM) EQ-Mode Firmware (Ver.03.27) Release Note
Date: Jan. 6, 2010


TELESCOPE SUPPLIERS - SKY-WATCHER TELESCOPE (http://www.skywatchertelescope.net/swtinc/customer_support.php?id=109&class1=1&class2=101)


1. Fix the bug in the SAO catalog regarding disabling the key-pressed slewing. Problem: Unable to drive and slew the telescope with the directional keys after browsing the SAO catalog. Result: The directional keys are properly activated after browsing the SAO catalog.

2. Fix the bug in the User Object coordinate editing. Problem: In the User Object function, under RA-Dec format, when the user enters an object with a declination angle between 0 and -1 degree the value becomes positive after the coordinates are saved. This causes GoTo pointing inaccuracy. Result: The user-entered coordinates are saved properly.

3. Fix the error in the database of NGC, IC catalogs. Problem: In the NGC and IC catalogs, the coordinates of the objects located between 0 and -1 degree in declination always read as positive. This causes GoTo pointing inaccuracy. Result: The coordinates are read as their true values.

[renormalised]

That's definitely a software fault. What it sounds like it's doing is computing Alpha, then when you go to try an alignment on Canopus, the software then seems to think the telescope should be pointing north, so it takes 180 degrees off the alt-az for Canopus and slews the scope around to that point. It's almost like it suddenly forgets where its pointing and then decides it should slew to the north. Try aligning with northern stars only and see what happens. If it aligns OK, then there's something buggy with it recognising the Sth Hemisphere. But if it does the same thing as before, then it must be getting north and south mixed up.

What I'd do is get the firmware previous to the version you now have, wipe the controller chip clean and install the old version, then add the latest version of the firmware, skipping the version that's in there, now. It's obviously screwy to the point of being nearly unusable.

[GeoffW1]

Hmmm, sounds like a good idea for me too.

Cheers

[Strawb]

Lined up accurately on Alpha Cent - the machine decided on Vega as the next star so I let it do that - 180 out and then when the machine asked me to centre Vega I did - all 180 degrees back and it accepted this with a quick flash of 'recalculating' and then was all good.Dialed up Antares as one in between the alignment pair and slewed straight to it direct and centred in the EP. Tried it on a few others and all good so back to Antares and tracked for over an hour with no probs. :thumbsup:

Still couldnt update the firmware though:mad2:

[Andy Walters]

Please note your 'scope is an Alt/Az design, you should point it level and NORTH before you do two star align.
Andy.:)

[renormalised]

Yes, but it should have a N/S switch so you can align with the SCP as well, unless it doesn't have one. In which case, you have to align with the N all the time, before you do any star alignment.

[Strawb]

Unfortunately I cannot find any such reference method. We had success by the method noted before however we aren't satisfied that we have found the problem. There doesn't seem to be a reference point with which to align to either pole - if you park it at 'home position' and then set up on that it still goes the wrong way. You can park it at zero altitude and the scope is infact 20 deg. All rather confusing.

[Andy Walters]

I've used Synscan Alt/Az on my tracking dob, no reference to N/S, just make home position pointed north and level.
Andy.:)

[Liz]

Have now got the scope back home, so will give it a go tonight, weather permitting.
Will do that Andy. :)

cloudy + cloudy = cloudy : (