1. Simulation Curriculum Corp.
  2. Community
  3. SkySafari 6 | SynScan WiFi Beta Testing
New post
0

[SynScan WiFi Beta Testing] Possible BUG or feature is not developed yet: AZGTi mount position

Hi,

I do not know if it's normal behaviour or at this beta phase this function is not complete yet, but I have problem with mount positioning. I can describe two scenarios, root cause might be the same, no celestial coordinates coming from the mount, only "raw data".

1. In case of using SkySafari only

- I connect to the mount via SkySafari app
- Mount position information show to default, towards NCP regardless its actual position
- Star alignment is not possible, if I try to set the mount to a certain star and press align button in SkySafari, I receive an error message: "Command Failure - Your alignment target is too far from the telescope's actual position. Please make sure yiu selected the right alignment target."

2. In case using both SynScan app and SkySafari

- I set up the mount in SynScan via the normal way, goto works properly with SynScan
- I open SkySafari and connect it to the mount
- SkySafari's telescope direction points to a different part of the sky, far from the telescope's real position which makes goto function useless, the telescope coordinates are completely wrong in SkySafari

If I compare how it's working via the old method with two IOS devices, there is no problem. In this case I use one device with SynScan and an IOS device with SkySafari - standard SynScan connection, NOT SynScanLink!

- I set up the telescope mount with one device using SynScan app, goto is working properly with it
- I set up another device with SkySafari conecting to the first device's IP address via the old SynScan connection
- SkySafari shows the correct telescope direction, goto is accurate

Used equipment:

SkyWatcher AZGTi mount, firmware version 3.20 (standard, AZ mode)
iPhone 8 IOS version 13.4.1
iPhone SE IOS version 13.4.1
SynScan app version 1.18.3
SkySafari Plus beta 6.6.5.1

Date Votes

49 comments

  • 0
    Avatar
    K

    Thur 16th April 2020

    Hi

    Tonight, first time outside testing and I had the same issues as Tamas.

    SynScan

    Seemed fine and I could align to Venus, this was after aligning the mount physically using Sharpcap.

     

    Sky Safari

    Tried the align function anyway, but got the following error Fig1.

    Fig1

     

    Then for general navigation, using Sky Safari the cursor(circle and cross hairs) was fixed, I commanded it to move to Capella, but the mount literally just kept rotating(Fig2).

    Cursor seemed like it was locked in position on or near to Polaris, trying to move, but could not.

    Fig2

  • 0
    Avatar
    Luis Trumper

    Hi Keiron:

     

    So what next? Waiting that you develop a new version that fix the bug?

     

    Thanks

    Luis

  • 0
    Avatar
    K

    In addition for me, the last few nights have either been too windy or cloudy!

  • 0
    Avatar
    Jay Sottolano

    Keiron,

    I opened a new "Bug" because the documentation associated with the Beta is incorrect.  It is the Router address or the address that shows up when you connect within the SynScan application on IOS.  In response to some others, almost every planetarium program requires that the alignment be done natively first, either hand controller, SynScan Pro app, etc..  Even SkyX from Bisque requires an initial alignment..

  • 0
    Avatar
    K

    Jay hi

    Fair enough, I was really just adding as a cross reference.

    Hope you are well.

    Cheers

    Keith

  • 0
    Avatar
    Tamás Fehér

    Hi Jay,

    That's my problem, yes. If I do the initial alignment in SkySafari, the coordinates are completely different in SkySafari: it is far away from the position what is visible in SynScan app. It seems celestial coordinates are not coming from the mount to SkySafari. It does read Alt-Az movement, but the real position is completely different compared to that is visible in SkySafari app. It seems SkySafari does not read alignment data from the mount only "raw coordinates".

    Cheers,
    Tamas

  • 0
    Avatar
    Jay Sottolano

    Keith..  Not a biggie, but will make it clearer and also avoid future issues when live.  Suggest you look at the automatic transfer as I outlined with Luminos. The handshake between SynScan Pro and the app is seamless and invisible to the end user.  A much more preferable solution.

    Tamas ..  The "real" coordinates are loaded into the mount from SynScan Pro, from that point on, SkySafari and anyone else's planetarium software can pick that up.  When you think about it, it would have to be that way.  SkySafari cannot initialize the position.  That software resides in SynScan Pro (or the hand controller talking to the mount).


  • 0
    Avatar
    Jay Sottolano

    Keith...  Just another thought on documentation as it relates to initialization.  The same is totally true for any version or platform of SkySafari.  The mount HAS to be initialized first via the hand controller or the SynScan Pro app..

  • 0
    Avatar
    Tamás Fehér

    Yes, Jay, it should work like that. I meant that once the mount know celestial coordinates after the alignment, that could be read out by any planetarium app - just like Luminos does. But SkySafari currently ready out some completely strange position and no way to have it corrected in SkySafari. That's why I started this topic as this is probably not a bug but an incomplete feature at this phase of development and beta testing.

  • 0
    Avatar
    K

    David Parks had some brilliant documentation on all of this(pays to read all of them).

    One of the suggestions was in SynScan Pro:

    EQ Home User Object should be Axis 1 = -90, Axis 2 = 90

    AZ Home (Mode North Level) User Object is Axis 1 = 0, Axis 2 = 0

     

    Great for either initially setting up or for when you pack away.

  • 0
    Avatar
    Jay Sottolano

    Tamas,  I'm not sure I'm totally following your post. Any planetarium program, be it Luminos or SkySafari cannot read positioning of the mount unless it is linked first to the alignment procedure.  What I think I'm hearing you say (and please correct me) .. Is that once the mount is initialized and then pointed at something, that any planetarium software should be able to pick up the location from the motors. The location is being stored in SynScan, so that is why they have to be linked in order for the Planetarium software to read out the location.

    As an example.. You should be able to align with SynScan Pro, use SynScan Pro to point to Arcturus for example, link to a planetarium software and at that point the planetarium software "should" be looking at Arcturus as well.  If you do the above, but do not link SynScan Pro, then start up SkySafari, there is no way for SkySafari to know where the scope is pointed so the read out will be wrong.

  • 0
    Avatar
    Jay Sottolano

    Keith... I use both as well when setting up.. Just a reminder to all, when setting up to do North and Level, use a compass app on your device but using true north.. many default to magnetic north. If using a hand compass, account for the displacement from Magnetic North at your location.

  • 0
    Avatar
    Tamás Fehér

    Jay, maybe I overcomplicated a bit. There are two situations:

    1. If I don't make alignment in SynScan app, SkySafari points to 0 north 0 altitude.

    2. If I make the alignment in SynScan, SynScan position is corrent, I mean if I go to any star the mount will do it correctly, but if I switch to SkySafari, it says the telescope is pointing to a completely different position on the sky.

    And that is my problem. If I use two devices, one with SynScan and the other with SkySafari and set up the equipment with SynScan, it will read the correct position from the other device's SynScan app. But If I use one device align the scope with SynScan and use SkySafari with SynScanLink, it won't show the correct position but something completely different! I am able to slew the mount, but all goto command will go to wrong directions - consequently wrong, same degrees away, all the time.

    I can not explain it more preciseliy, hope now this explanation is clearer than my initial one.

  • 0
    Avatar
    K

    Keiron hi

    Can I please ask what is the current situation regarding the potential bug with the current version of the app ?

    We seem to be due a lot of dodgy weather over the next several days anyway, so no rush, just curious.

    Kind regards

    Keith

     

  • 0
    Avatar
    David Parks

    Best Practice is DO NOT USE TWO CONTROLLERS, aka Skysafari and Synscan.

    Controllers connect to the AZGTi in either AZ Mode, or EQ Mode. For Skysafari, this is set in the Telescope Setup by selecting the Mount Type: Alt-Az. GoTo, or Equatorial GoTo (German). For Synscan this is selected when connecting, either Alt-Az Mode, or Equatorial Mode.

    When the AZGTi powers up the (Axis1, Axis2) are set to their Default position, regardless of where the telescope is pointing.

    The first controller (Skysafari or Synscan) to connect will set the (Az, Alt) coordinates of the mount and the corresponding Default (Axis1, Axis2) position of the motors, according to the connection mode, regardless of where the telescope is pointing.

    For AZ Mode, this will be (Az, Alt) = (0, 0), (Axis1, Axis2) = (0, 0), representing North-Level. Skysafari will position the telescope indicator due North on the Horizon.

    For EQ Mode, this will be (Az, Alt) = (0, Your Latitude), (Axis1, Axis2) = (-90, 90), representing EQ Home. Skysafari will position the telescope indicator at the Celestial Pole.

    Best Practice is to power on the AZGTi and connect the controller (Skysafari or Synscan) with the mount already in the correct physical orientation (North-Level, EQ Home). This ensures that the telescope is pointing where the controller (Skysafari or Synscan) thinks it is. (And ensures that Sync commands, aka Sakysafari Align, are not too far away)

     

    All things being perfect, the scope, mount, and controller are all in agreement, knows exactly where it’s at in time and space and can perfectly center any object you want to GoTo. No alignment needed; you’re done. But nothing is perfect, so Alignment serves to correct the real world errors between (Az, Alt) and (Axis1, Axis2) caused by the inaccuracy of setting the scope perfectly North, or Level (in AZ Mode), or polar aligned (in EQ Mode), or by being 9 minutes 22 seconds West of your 1 hour wide Time Zone…

    Star Alignment serves to build a “Sky Model”, or “Algorithm” that describes the difference between your mount’s (Axis1, Axis2) and the real world (Az, Alt) positions. This Alignment is calculated by centering stars, and is held in the controller (not the AZGTi).  The AZGTi only knows the (Axis1, Axis2) positions of its motors, and supplies this to the Controller(s). The Controller(s) interprets this into (Az, Alt) with alignment correction if available. The problem with using more than one controller is that inevitably they will seriously confuse each other. DO NOT USE TWO CONTROLLERS, aka Skysafari and Synscan.

    Here’s a good way to screw things up: Connect both Skysafari and Synscan, and then loosen the AZGTi clutches. Surprise! Skysafari reads the encoders, so will update the telescope indicator even when you manually move the scope with loose clutches. However, Synscan has reading the encoders turned off by default, so you will see how quickly things can get wonky between two controllers. Personally, I think this is a great feature of Skysafari (encoders on by default), very useful for visual observers.

     

    Align(ing) in Skysafari tells the AZGTi where it is really pointing compared to where it thinks it is pointing (and builds the alignment/goto corrective model), but the AZGTi will not accept Sync commands from half way across the sky… you have to be reasonably close… I’m not sure exactly what the tolerance is, but I seem to remember something like 6 – 8 degrees.  This is an AZGTi thing, not a Skysafari thing. “But my telescope is reasonably close, so why do I still get the too far from actual position error?”. Because your (Axis1, Axis2) is too far away from (Az, Alt) regardless of where the telescope is pointing.

    So follow the aforementioned Best Practices by setting your AZGTi up in the correct position, either North-Level or EQ Home, BEFORE you power it on, and DO NOT USE TWO CONTROLLERS.

     

    Simulation Curriculum has given us this wonderful native support for the AZGTi and other Skywatcher Synscan Mounts, which seems to work perfectly in my testing. The whole point is to not have to use Synscan, so don’t.  :)

     

  • 0
    Avatar
    Luis Trumper

    Hi David:

     

    Thanks for your explanation very thorough as always. A quick question:  Sky Safari does not include any alignment procedure with two or three stars what  dramatically increase the accuracy of your alignment. How do you replace it?

     

    Thanks

    Luis

  • 0
    Avatar
    David Parks

    Luis, great question, and I don't have a complete answer... yet...  not enough clear sky time... however.  Instead of a "Do a 2-3-Star Alignment First, then Turn You Loose" type of approach, Skysafari seems to allow you to just simply use the Align button to enter corrective alignment information as you go.   I cannot tell yet from observation/experience if each subsequent Align accumulates and adds up to an increasingly accurate correction.  That is currently on my list of "To Test" activities :)

     

    I have my AZGTi setup with the ASIAIR Pro and new Redcat 51 in EQ Mode for Imaging, so like a kid in a candy store I'm trying to fit everything in to the few clear sky moments we get :)

     

    Here's my overall thoughts for the Skysafari/AZGTi combo:

    Skysafari is a great controller for AZ Mode + Visual.  Easy to setup in North-Level and get right to it with your favorite Oculars.

    EQ Mode doesn't make sense for Visual... unless you enjoy contorting your head/body into awkward positions...  and Skysafari doesn't make sense for Imaging, because if you are imaging then you already have access to GoTo, Platesolving, Mount Control, etc.

     

    Point is, I need to convert my mounting back to AZ Mode, and replace the imaging train with an eyepiece to continue my Skysafari testing :)

     

     

  • 0
    Avatar
    Jay Sottolano

    Hi David..

    I think there are parts of your procedure that are correct and others not.  First, by Controller do you mean SynScan Pro app or a physical hand controller (not that it is totally relevant per se).  The AZ-GTi cannot be aligned through any Planetarium software, even one as feature rich as the The SkyX, and the mount needs to be initialized (not just in position but location, date, time, etc.) before the handoff with SynScan Link can provide correct information to the SkySafari, Luminos, etc..  There is constant communication back and forth when using the controller (again either hard wired or SynScan Pro). 

    Additionally, remember that the AZ-GTi has dual encoders so releasing the clutch does not over write information or lose position just because you moved the mount from one location to another.  SynScan still knows (or should) where you are.  Also, keep in mind that the Right Arm - EQ firmware mode is not an officially supported mode for the AZ-GTi.. Not saying it won't work (and a really nice looking setup you have there)... but I think you'll find it's not quite as critical an EQ platform for longer run exposures..

    Again, the SynScan Link API to wireless (this also includes the WiFi dongle for the larger mounts like the EQ6-R Pro) is the first step to initializing the mount and does remain in communication with the Planetarium software throughout. In fact, within Luminos, you can switch back and forth.  Yes, once initialized (not just aligned) you can function almost entirely in the planetarium up, but you really can't start without it. Again, I just don't think it's the correct approach to suggest that not to use Two Controllers (again not sure if you mean SynScan Pro App as a controller).  I'd be extremely curious to see if you can operate the mount in a full fashion without any initialization from SynScan Pro.

    Jay S.

  • 1
    Avatar
    David Parks

    I absolutely and without question mean that you can operate the mount in full fashion without either the Synscan, or Synscan Pro app.  Skysafari provides date/time/location information, and in additional to a defined starting location (which is either North-Level in Az Mode, or PA in EQ Mode) gives everything needed to perform GoTo's.   (Of course accuracy is dependent upon quality control in the manufacturing of gears, date, time, setup... etc).

    Alignment can certainly (and has to) be done by Software, Planetarium or otherwise. A Hand Controller is just a computer running software.   "Alignment" is simply knowing the difference between two sets of coordinates, one is the motor positions, the other is the real world target position.  It is the controller (be it Hand or App) that builds (by asking you to center stars) error correction information, calculates the offset between motors and real world, and sends "corrected" instructions to the mount(motors).  Those error correcting offsets can be based on simpler 1-star alignments, or more complex 3-star spherical trigonometry.  But ultimately it's all done by the software app, in this case Skysafari, which seems to simply use the Align button to add additional points to it's alignment model.

    As for the AZGTi's encoders, the controller does indeed "loose position", just because you moved the mount with loose clutches... unless you instruct the controller to use/read the encoders.  Synscan defaults to encoders off.  Skysafari does in fact read the encoders without being told to do so.   Just to be clear, the AZGTi always knows where it's motors are, relative to it's power up state.  Upon power up, the AZGTi sets it's motors to (0, 0)  (connecting any controller, hand, synscan, skysafari in eq mode will reset that to -90, 90)  But lets stick to AZ Mode for simplicity.  The AZGTi will always know it's position relative to it's powered on (0, 0) state regardless of where the telescope is actually pointing.  It is the job of the controller to manage the relationship between motors and where the mount points.  If the controller moves the motors 10 degrees, then the controller KNOWS it moved the mount 10 degrees.  But if you move the mount manually by loosening the clutches, the controller does not know the mount moved, because the motors did not move (the clutches were loose), unless you have dual encoders that can provide this information to the controller, and the controller is paying attention to them (Synscan does not by default, you have to turn it on every time)

    The Dual-Mode Right hand firmware is indeed experimental, however, I assure you that the AZGTi can perform extremely well as an EQ Long Exposure Imaging Platform.  Of course it doesn't perform like more expensive mounts with tighter and more costly manufacturing materials/tolerances, and PEC capabilities.  But a good copy of the mount (like mine), can easily do long exposure guided imaging.  Although I usually keep my exposures between 1 and 4 minutes because the of light pollution, I have demonstrated consistent and repeatable 20 minute guided exposures.  A very capable EQ Platform it can certainly be. (Plenty of evidence over on Cloudy Nights Forums)

    On a PC running Microsoft Windows, unfortunately you need to run the Synscan for Windows application, but only because it provides the ASCOM interface/drivers, however, on other operating systems this isn't necessary.  Linux and devices such as the ASIAIR and Stellarmate use INDI drivers to completely control the AZGTi without Synscan.  Indeed that is the very nature of what we are Beta Testing with Simulation Curriculum, their native support/drivers for the Synscan Mounts (without the Synscan app).

    So again, I absolutely mean that you should be using Skysafari alone, without any other controller, be it Synscan App or otherwise.

    1. Position the mount correctly (North-Level or EQ Home)

    2. Turn the AZGTi on.

    3. Connect your iOS device to the AZGTi wireless access point

    4. Launch Skysafari Beta, and Connect

    5. Use Skysafari Goto to slew to your target (SS can do this because it gets GPS/Date/Time from your iOS device, and assumes a starting position of North/Level.. what you call 'initializing the mount')

    6. Use Skysafari Align to correct for all the minor errors due to inaccuracies of date/time/north/level, etc.

    As you continue to Align objects in Skysafari, the GoTo's will get increasingly accurate... 

    And just to be clear, when I say "minor errors" and "increasingly accurate", i'm talking about a couple of degrees.  Skysafari went from an approximate 3 degree error in my initial setup to 1 degree GoTo accuracy after 2 Align(s). (Az Mode)(10mm 60degree FOV eyepiece yielding 25x in the 250mm Redcat)  No Synscan Needed.

  • 0
    Avatar
    K

    10:45

    David hi

    Ok,  I was under the impression(rightly or wrongly, coupled with being new) that the new version of the App was purely to enable Users to use just one device and I also made the assumption you always needed to use both Apps(SynScan and SkySafari) to make it work.

    I therefore, also assumed that the process was along the lines of(speaking for myself & off memory due to bad weather):

    1) Set the Mount and AZ-GTI pointing towards Polaris(EQ_Mode) approx(Default EQ-Home position).

    2) SharpCap Polar align.

    3) Then using just my IPhone(New Beta App installed), connect to the AZ-GTI.

    4) Then I was using SynScan Pro to align on Two stars(then leave running in the background).

    5) Then I was going to use SkySafari App to then navigate/Goto etc for my Photography etc.

     

    So, if I am reading you correctly, are you saying pretty much cut out Step 4) ?

    It's not dark her at present, but I will have a little play around later today, just to step through the process - thank you for detailed info as ever.

    Kind regards

    Keith

     

    11:52

    Just popped outside(daylight) and for a quick test, just with a bracket acting as camera/pointer.

    1) Set the mount/tripod and AZ-GTI up,  approx pointing North and in the EQ-Home position(pointing at Polaris'ish).

    2) Powered on AZ-GTI, connected the IPhone to the AZ-GTI wifi & started SkySafari(Beta).

    3) Goto Polaris - Yes approx(bright daylight).

    4) Goto Mars - Yes approx (bright daylight, SW on the horizon for me).

    5) Goto Sun - Yes.

    6) Goto Mars - Yes etc.

    So brilliant, the only issue(and probably down to me not reading the documentation) is when I pointed at Mars for example I hit Align and it said the scope was pointing too far away or not in the right position.

    Although, now I will test properly tonight, weather willing.

    Previously, I had both apps running(SynScan Pro and SkySafari), so thats probably me not understanding things.

    Initially, even now I did start SynScan first just to position the AZ-GTI in the EQ_Home position, I will look to create a similar target in Skysafari and I will read up on Align.

    Cheers

    Keith

     

    Slightly Later

    Summary so far for me

    **********************************************************************

    So,  from Keiron's basic instructions which did not mention the SynScan app and to which I for reasons unknown added that to the start up.

    This appeared to cause my AZ-GTI mount to continuously rotate on Polaris and to freeze the GoTo Reticle in the same position.

    David’s great notes then clearly brought it home,  what was needed to be done and they also explained (I believe) why, the Align error message appeared “stating out of range” (especially as I was roughly setting things up in daylight to start with, so was probably a way off target).

    Also I am getting a better understand now of how it works, especially the alignment etc.

    Thank you all and I will endeavour to test properly tonight.

    **********************************************************************

     

  • 1
    Avatar
    David Parks

    Yes, there has been some confusion about the 'just one device' thing...   the 'just one device' thing is a limitation of iOS, because it doesn't properly multitask.  Skywatcher designed Synscan to not only be the controller of their mounts, but also to be the conduit through which other controllers could connect and gain access to the mount.  In the older case of Synscan Hand Controller, this connection was made via the serial port located on the bottom of the Hand Controller.  Synscan plays "middle man" to your PC/ASCOM or whatever you are connecting.  In the newer case of the Synscan App, it exposes the mount to other software.  Basically it's the API (Application Programming Interface) which allows two applications to talk to each other.  This works just fine on operating systems such as Windows, and Android.  However, Apple's iOS doesn't properly multitask, so even though you can have Synscan running in the background it is not really active, and therefore cannot play it's role as middle man between the mount and other software (Skysafari).  Simulation Curriculum has caught a lot of un-warranted and un-deserved 'flak' because their controller (Skysafari) wouldn't control Synscan Mounts on iOS. The problem lies (or did) with Skywatcher, for not making their API available, which forces Skysafari to use Synscan App as the API, which doesn't work on iOS because of the fake multitasking.  The exciting thing here is that Skywatcher finally made their API available to Simulation Curriculum and now we get to Beta Test Skysafari's direct control of Synscan Mounts without needing the Synscan App to serve as the API.

    Hello Keith :)

     

     

     

  • 1
    Avatar
    David Parks

    You can safely use Sharpcap to Polar Align your mount, as this process only results in the physical correction of the mounts base position. 

    When you power on the AZGTi, it automatically resets its (Axis) and (Az/Alt) to the EQ Home position (Polar Aligned).  So there is no need to connect Synscan and tell the mount to go there, it is already there.  You just have to have your scope actually already pointing there in the real world.  In fact, connecting Synscan will update the mount's Az/Alt position "contaminating" what would otherwise be a clean starting initialization for SkySafari.

    Now, when Synscan is your controller, with encoders off by default, you can turn the mount on, and un-clutch in order to physically swing the scope into the correct starting position, thereby making mount and scope agree.  With encoders off, the Axis stays at (-90, 90) and you are manually moving the scope into (Az/Alt) agreement.  (You can also use 'Reset Alignment' to zero/home the Axis-Az/Alt, which is why you should only 'Reset Alignment' when your scope is in the North-Level, or EQ Home position)

    However, with Skysafari which always has encoders on, there is no disconnect between Axis and Alt/Az, even with loose clutches (because encoders don't read the motors, they read the axis), the mount will update it's Axis even when you manually move the Az/Alt.  So you can't manually move them into agreement, the encoders makes the offset difference persistent. It's like chasing a target that makes the exact same moves as you do.  Skysafari does not have, or does not have an obvious "Reset Alignment" action, in order to zero/home the system.  I say "obvious" because I do note that while Align(ing) stars in Skysafari, I sometimes got a "Align, or Restart Align" message, and I havn't fully investigated this yet.

    The best way to ensure Axis, Az/Alt, and Controller are all in agreement is to simply power up the AZGTi already in the correct EQ Home position. 

  • 0
    Avatar
    Jay Sottolano

    David...

    Partially true. There has been communication going back well for over 2 years and the API came out a while ago as SynScan Link on IOS. In part, yes, there was no open API, but also there was delay within the SkySafari Team. Some of it had to do with people leaving, the project not getting started, etc. The opportunity had been there long before that though..  Also agree that IOS's design inhibits a better solution, but I still contend (and will try your methodology) that full interaction with all of SynScan's functionality cannot be totally achieved in SkySafari by itself.  Again, I will test here as well... (and do appreciate your efforts)..

    Jay S.

  • 0
    Avatar
    K

    Jay good afternoon........

     

    David hi

    Thanks again for the detailed explanation and Hello!

    Ok, so I think I am clear in my mind and I did also wonder about the “Reset Business” as SynScan has that, if required how etc, but…...

    So,  I will try and get out tonight on the patio:

    Sharpcam Polar align (Guide Scope and Camera) on the same target checked before hand they are in sync.

    Then, turn the AZ on, then once initialised.

    Goto to few targets,  initially say 3 or 4 and as I do so, ensure I correct and alignment(haven’t actually used it yet, so not sure what the order is) and in theory this makes the targeting more precise, the more objects you visit?

    ie: Goto Mars…….actual physical scope stops short(target on edge of camera view finder)…….But SkySafari shows on target……..Hit Align and then use the < arrow buttons> ?  

    And in theory, by doing a few of these, corrects any misalignment issues(self corrects), sync physical to DB etc internally/app/software.

    Cheers everyone

  • 1
    Avatar
    David Parks

    Jay,

    Forgive me for the point of clarity, maybe I am mis-understanding...   however, you say "...that full interaction with all of SynScan's functionality cannot be totally achieved in SkySafari by itself".

    The SkySafari "SkyWatcher SynScanLink" does not interact, speak with, or otherwise have any knowledge of Synscan.  In all cases I use the term "Synscan" to refer to the software application.

    So indeed, and in fact I agree with your statement that "full interaction cannot be totally achieved" because in truth NO interaction happens, not even in part with SynScan.  The SkySafari SynScanLink communicates directly to the mount.

    The functionality of Synscan is not stored in the mount.  The mount does not store alignment models, lists of 1, 2, 3 star coordinates or any other type of corrective information that could be subsequently used for functionality, other than the (Axis1, Axis2) and the (Az, Alt).  The mount only stores those two sets of coordinates. Period.   Everything else is in the controller, be it Synscan, or Skysafari.  The controller (Synscan or Skysafari) manages and calculates the relationship between the two sets of coordinates, first through initial start up values, and later with corrective input via alignment methods which are requested by, maintained by, and used exclusively by that controller only, be it SynScan, SkySafari, Hand... etc.

    Of course there is basic communication between the controller and the mount, which includes motor commands such as "move", "turn tracking on", "turn tracking off", and sometimes, depending on make, model, firmware, controller… the mount might even send an ACK back to the controller, saying "Yes Master", "Did That".. but otherwise and regarding the topic at hand, the mount only stores and communicates the two sets of coordinates.  It is the job of the Controller to monitor, calculate, correct, and update the mount with the (Az/Alt) translation of the mounts (Axis).

    If a second controller updates the mounts (Az/Alt) coordinates (stored in mount memory), then it does so with that controllers own understanding of the Axis-Alt/Az relationship.  It does not consult any other controller, and any other controller maintaining its own independent understanding of the Axis-Alt/Az relationship will potentially, and most likely not be in agreement.  In this case, two heads are not better than one... the left hand doesn't know what the right hand is doing. It only knows what the mount can tell it, which is simply the (Axis) and now changed (Az/Alt), which now defines a relationship that does not agree with that controllers stored understanding (alignment).

    Skysafari does not need, use, nor can it even access, Synscan's functions, features, stored information, including alignment/corrective relationship calculations.  It has all of it's own stored information, albeit one might describe Skysafari's Align routine rather basic.  I personally think the simpler "Object Align" functionality of Skysafari is totally adequate and all that is needed to achieve complete functionality and command of the mount.

    It's true that Synscan offers several different, and some more complicated alignment routines, in the traditional 2 and 3 star varieties, but Skysafari SynscanLink does not need and does not have the ability to access the information that Synscan collects after running these routines. Neither does Skysafari SynscanLink send commands or information to Synscan, as a conduit, passthru, or interpreter, to the mount or otherwise.  There is exactly ZERO direct communication between SynscanLink and Skynscan.  There can only be CONTENTION over who controls and updates the mounts stored (Az/Alt) coordinates, and thereby the relationship to (Axis).

    I hope this makes sense, and I look forward to the results of your testing :)

    D

     

  • 1
    Avatar
    David Parks

    Keith,

    After your Sharpcap PA,  simply turn off and back on the AZGTi and Connect Skysafari.  At this point everything is theoretically aligned.

    Just select a target in Skysafari and press GoTo.  If the object isn't centered (most likely), then use the Skysafari Arrows to center the object, it should already be close, maybe inside, maybe just ouside your eyepiece field of view.  Use the Arrows first to center the target.  Then, once centered, press Skysafari Align button.

    Done

    No need to rush through 2 or 3  GoTo/Aligns before getting down to business.  Just Connect and GoTo, and Align as needed as you go.

     

    The whole paradigm of needing to do some kind of "Initialization", complicated alignment routine, and standing on your head before you can effectively and accurately Point, Track and otherwise Use a mount is an old adage from days gone by wherein this activity was necessary and required by controllers that did not initially have access to information (such as date/time/location, etc).   In today's GPS enabled devices, controllers (like Skysafari)  have complete access to all this information, needing only to know where the scope is actually pointing.  They get this information first by assuming you are starting in the correct Home position, and then later by correcting the small errors through Alignment information and internal calculations.

     

    Indeed,  many Imagers never align their scopes via controller enforced routines that product marketeers demand their software developers include for the ill-informed customer.  The Imager simply platesolves the image from their first GoTo, which syncs the precise (Alt/Az) to the mount, which informs today's controllers with the only missing piece of information (current position with corrections).  Visual Observers perform the same platesolving service by visually centering an object and pressing the NOW button.

    incidentally, the accuracy of "Visual Platesolving", aka moving the mount with arrows and confirming the target is centered, can be increased by using a crosshair reticule eyepiece, by always approaching the star center in the same up/right direction (to eliminate motor backlash) and other disciplinary behaviors.

  • 0
    Avatar
    K

    David


    Thanks, it is like a training course for me, much appreciated.

    And that answers my previous question brilliantly on Aligning.
    Incidentally and me not wanting to assume anything, for example if I say GoTo object X and the AZ works its magic and places the cross hair bang on target.

    Q1) Does the AZ always track (object X) by default ?

    Q2) And I assume, if it was tracking a star, planet, comet or satellite, depending on the type, does it automatically compensate, what am I trying to say, is the tracking movement fixed or as you have possibly eluded to in previous replies, the app/software controls that part?

    Once again thanks for the detailed replies, great for me, ok others may know all of this already, but……

    Cheers
    Keith
    Ps: Weather looking semi-good(partially cloudy tonight) here and we have been busy just getting another bee hive ready, so side tracked!

     

  • 0
    Avatar
    K

    Just a thought, which I could add as a “future enhancement” on the correct section on the forum.
    Whilst I have a intervalometer, it was easy and nice to use the photo-taking program that was built into SynScan.
    I have just had a quick look and I do not think SkySafari has that, is anybody else able to confirm that facility is not there ?
    Personally I would find it useful.

  • 1
    Avatar
    David Parks

    Basically yes, the AZGTi will begin tracking automatically.  This is accomplished by the Controller sending the mount a "Track On" command, along with a Tracking Rate.

    In the case of Synscan, there are only 3 tracking rates, Solar, Lunar, and Sidereal.  Solar is obviously for the Sun, and only available if you turn "Observe Sun" on in the Advanced Setting, for which you have to endure a warning about looking directly at the Sun, which apparently isn't a good idea...  Lunar is for Earth's Moon, and everything else including Stars, Planets, Comets, etc will use Sidereal.  There is no (man made) Satellite tracking.

    In the case of Skysafari, although it will turn tracking on automatically, I do not know how many rates/objects types have been provisioned.  I think we can assume the same three which are quite standard, Solar, Lunar, and Sidereal. 

    To be clear, the mount does not govern tracking, it only accepts commands from the controller (Skysafari or Synscan) related to the immediate tracking needs... aka "Turn On", and "This Much".  The controller governs the tracking and sends updated commands to the mount as needed.

    In the case of EQ Mounting... its really easy...  "Turn On" "This Rate" and your good... until you want to "Turn Off" because everything moves around one Axis (Polar) at a constant Rate (Sidereal). RA/Dec is considered static (except of very long periods of time, Epochs).

    AZ Mounting is much more complicated... unless you live at the North/South Pole :)  Alt/Az is constantly changing at a variable rate... example in the North Hemisphere when the object is rising in the east, the motion is "Up" at a relatively fast rate and, and "Right" at a very slow rate, the rate of "Up" continues to slow down until the object reaches the meridian in the South, at which time the mount has to start moving "Down" at an ever increasing rate until the object sets in the West.  Additionally the rate of "Right" motor spin speeds up until meridian, and then slows back down towards setting in the West.

    So, for AZ Tracking, the controller (Skysafari or Synscan) has to constantly send a tracking rate update to the mount, for each motor.  And its different for each location on the planet and for each object in the sky.  The mount doesn't do any of this heavy lifting calculation, it just says "Yes Master" to the constant updates from the controller.

     

    If you will indulge me a moment, and try this on for thought:  In TRUTH, any mount, every mount, including the AZGTi always performs better in EQ Mode.  I know that the AZGTi has a bad reputation for not working in EQ Mode (this I assure you is operator error), and I know Skywatcher says they don't support EQ Mode (the reason being more to do with that operator error thing)... but that's all nonsense.  The quality of the manufacturing is the same regardless of how you tilt the mount.  The precision of the gears is the same, regardless of how you tilt the mount.  So, mechanically, physically, there is no difference in performance... but operationally, EQ Mode is in natural harmony(alignment) with the orientation of the major source of movement (rotation of the Earth), and so things like "GoTo" and "Tracking" which are Performance functions are easy to accomplish and do not need very much correction... just a simple "Go from  here to there" and "Turn On at Sidereal until I tell you to Turn Off".  While Alt/Az has to do a lot of very complicated math to translate the wonky tilted AZ Mode axis orientation.   Yes, it is AZ Mode axis orientation which is tilted at wonky angles... ever different and variable depending on where you are on the planet, while EQ Mode always has the mount axis correctly oriented "UP" no matter where you stand.   It is literally, and demonstrably true that every mount including the AZGTi performs better, more accurately, when EQ aligned.

    The reason Skywatcher doesn't support EQ Mode is because EQ Mounting is mostly and traditionally used for long exposure imaging, and a $300 mount does not have the manufacturing and material tolerances to achieve the precision people expect for taking pretty pictures.  Now, having said that, if you are willing to live within the tolerances of a cheap piece of plastic, you can operate not only in EQ Mode and do long exposures, but you will find the AZGTi performs better, as all mounts do, when compared to their AZ performance.

     

  • 0
    Avatar
    Tamás Fehér

    Having read through the very useful comments above, I came to the conclusion that the easiest way to set up the equipment is the following:

    1. Align the mount with SynScan app
    2. Slew the mount manually to 0/0 position
    3. Turn off the mount
    4. Turn it on again (this will reset the axis coordinates to 0/0)
    5. Connect SkySafari to the mount

    This will bring accurate positioning in SkySafari. But I have to mention this method is not as simple as Luminos does. With Luminos, just as Jay wrote, after aligning the mount with SynScan and conect the mount with that planetarium app, they do a simple handshake - no need to have any multitasking, Luminos simply receives the offset values for each axis from the other app. I think it would be the best to have this feature implemented in SkySafari, too. But until that, you can still follow this longer process above.

Please sign in to leave a comment.