Accessing MGEN-3 in Sharpcap 3.3 and dithering

[Moorefam]

Robin,
I should have read the manual more carefully, my apologies. I think I have now read all the relevant parts and tried again with 32 bit Sharpcap version (it complains about lack of memory c.w. the 64 bit and I have 16GB) . I have the correct drivers installed. I have tried the sequencer and live stack and in both cases I get cannot "connect to MGEN3". I am completely stuck.
Something else puzzles me. I have "dithering" between each sub even when MGEN3 is disabled but stars are round, with 1 min or 5 min subs so the mount is not being moved continually out of synch with the sky. MGEN3 is locked onto multiple stars and the correction graphs look good with about 1 arc sec guiding errors. I don't see jumps in the MGEN correction values coinciding with camera subs. I also don't see elongated stars. I do see DEC slowly changing in the EQMOD position display but haven't seen a jump when subs are taken. It makes no sense and I have to have missed something but what? Polar alignment looks good and the pillar is vertical, plate solving works fine with an correction of about 2 degrees. I have approx 0.4 arc sec/min mean dithering in Dec and 0.04 arc sec/min mean dithering in RA. I have no way of changing that. Sorry I had better post this elsewhere.

[admin]

Hi,

ok, so the two ways that you can attack this are

1) 32 bit SharpCap, MGEN.APP, do not set up dithering in SharpCap

2) 64 bit SharpCap, do not use MGEN.APP, let SharpCap control the MGEN

Don't try to use both MGEN.APP and the dithering settings in SharpCap.

Now, the reason that you run out of memory for the 32 bit version is that although SharpCap can pull some clever memory tricks for its own memory, memory used by the camera driver, MGEN.APP, displaying images, etc, cannot be optimized in the same way. With large resolutions comes the need for large blocks of memory to represent an image, sometimes there is no block large enough which can cause the out of memory error. Really the only thing to do in that case is (1) turn on binning or (2) switch to 64 bit ... or would be if it wasn't for MGEN.APP only being 32 bit

Anyway, from the point of view of running dithering within SharpCap, the correct settings (I think) are

* SharpCap settings, Guiding page : choose MGEN, set max dither step and minimum settle time
* Live stack guiding settings : choose 'monitor guiding application' , 'automatically dither' , 'reduce exposure while dithering ' and set the dither frequency as required.

When you tick 'monitor guiding application', you should see a green bar to indicate that SharpCap has connected to your MGEN. If you see 'Connection to MGEN3 guiding failed' then you need to dig a little deeper, but going to SharpCap settings, Logging tab and tick the box that gets additional guiding logging. Then untick and retick the 'monitor guiding application' box.

For instance if I turn on the extra logging and try to connect the the MGEN without it being plugged in, I get

Code: Select all

Verbose	22:07:37.373953	#9 	Guiding : SharpCap.Guiding.MGEN.MG3Comms.PollDevice :: Starting PollDevice()
Verbose	22:07:37.374951	#9 	Guiding : SharpCap.Guiding.MGEN.MG3Comms.PollDevice :: Completed (returned False) PollDevice()
Warning	22:07:37.381001	#9 	Could not connect to MGEN3 device																						
Debug  	22:07:37.381993	#1 	Notification (Status=Warning): Connection to MGEN3 guiding failed.	

in the log - basically SharpCap went looking for the MGEN and didn't find it. Of course you would expect this error when not connected (and probably a different error if you try to connect to the MGEN from SharpCap guiding but are already using MGEN.APP)

hope this helps,

Robin

[Moorefam]

Robin,
I have followed your instructions to the letter and when I click on monitor guiding application, again I get "not connected to guiding". I am wondering if MGEN comms is faulty? Shouldn't I see evidence of MGEN or its drivers in Win 10 Device Manager? Is there some other basic comms connect check I can make? I will be outside much of the evening/night tonight if it stays clear.

[admin]

Hi,

you do need to install the windows drivers for the MGEN from https://ftdichip.com/drivers/d2xx-drivers/

This is the download you want

Capture.JPG (24.14 KiB) Viewed 941 times

Once the driver is installed, I see my MGEN show up in device manager as 'USB Serial Port' inside the 'Ports (COM & LPT)' section of device manager - it will appear when you plug in the MGEN and vanish when you unplug it.

cheers,

Robin

[Moorefam]

I had already installed those drivers but did it again as you indicated and since you mentioned it, under ports in system I did find that it came up with usb com port 3 or something similar when I plugged MGEN3 into a usb port. However in Sharpcap in live stacking it still came up with "unable to connect to MGEN". I have found Sharpcap crashing a lot recently more than I am used to by the way. I use it in connection with Cartes du Ciel.

[Moorefam]

Robin,
Thinking about it, I can't see MGEN3 virtually in Sharpcap because it tells me that ASCOM drivers are faulty with a load of fault lines. I also can't dither with it. I do like it and for what I bought it, which was observing with my DSLR it was great, dithering nicely. Even now all I have to do is switch it on, press 1 button and it guides nicely but that's all though it will do apart from polar axis alignment. I think my apparent dithering may well be due to flexure between the guide and main scopes, so perhaps I should sell MGEN and try off axis guiding with Phd2? It is rather frustrating not to be able to get to the bottom of the problem. I don't try using the MGEN APP when trying to dither at the same time, as you told me not to try that. I wonder if it's only me having problems? Are MGEN support staff aware of any issues.

[admin]

Hi,

I haven't heard of anyone else having quite the same level of difficulty that you have - it's all a bit odd. I know there are other people using the MGEN in SharpCap, as far as I know without any major problems.

Be careful in your choice of OAG if you are buying one. I bought one a few years back and it turned out to be a horrible wobbly thing - no real use for guiding. I managed to make it almost usable by drilling and tapping some extra holes in the body to give more screw down tightening points, but even then it wasn't great. It sits in a box now and I use a decent 50mm guide scope.

cheers,

Robin

[Moorefam]

Robin,
Thanks for the heads up re off axis guiding. I wish I had access to another MGEN3 as who knows mine may have a fault? I have a new fast 16GM memory laptop so I doubt that is a problem.
I have moved the guide camera assembly from the tube side attachment point to the dovetail supported between the guide rails. I also have a 2nd dovetail on the other side to make a rigid cradle. I have been getting 1.5 arc min drift between 3 min subs which I am wondering may be due to flexure as it certainly isn't planned dithering. I used polar alignment in Sharpcap for the first time and found it quick and reliable. I see MGEN has a 2 year warranty for perhaps I should return it to 365 Astronomy and get them to test it with Sharpcap? I downloaded MGEN app again but although using 32bit Sharpcap I now get the window to choose cameras. it never works and just tells me my ASCOM driver has a fault. Most of the time I use the 64 bit version.
I now have ASCOM platform 6.6 ASCOM
MGEN.APP 1.0.0.36
EQMOD EQASCOM telescope driver 2.00W
Sharpcap 32 and 64 bit versions.
I have AWO ASI 2600MM and MC camera
ZWO ASCOM Driver 6.5.1.13
ZWO ASI Cameras driver 3.17.0.0
FTDI d2XX drivers

I will have another go outside when the sky clears again.

[admin]

Hi,

if I were you, I would test as follows to check the MGEN

1) 32 bit SharpCap
2) MGEN.APP (MGEN guiding disabled in SharpCap)
3) In MGEN.APP setup, select the 'Camera V2 Simulator' camera via the 'Choose' button - that is just a simulated camera that installs with ASCOM

That setup should mean that the only thing that is unknown is the MGEN, rather than using a real camera which could have problems with its ASCOM driver.

If you do that, you should see that MGEN.APP mirrors your MGEN screen and shows a log of all the things that the MGEN is doing - like this

Capture.JPG (104.46 KiB) Viewed 900 times

If you are seeing the screen of the MGEN and info in the MGEN.APP log then it's likely that your MGEN is working as it should.

cheers,

Robin

[Moorefam]

Robin,
I was trying that again when I read you reply and the result is that it tells me there is a fault with my ASCOM drivers and then this long message:-
System.DllNotFoundException: Unable to load DLL 'MG3lib\MG3lib.dll': The specified module could not be found. (Exception from HRESULT: 0x8007007E)
at ASCOM.MGEN.APP.Classes.MG3API.ReadDeviceInfo(Mg3DevInfo& pdi)
at ASCOM.MGEN.APP.Classes.MG3API..ctor()
at ASCOM.MGEN.APP.UI.MG3.Controls.Connect()
at ASCOM.MGEN.APP.UI.MG3.Controls.UserControl_Loaded(Object sender, RoutedEventArgs e)
at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs)
at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
at System.Windows.UIElement.RaiseEvent(RoutedEventArgs e)
at System.Windows.BroadcastEventHelper.BroadcastEvent(DependencyObject root, RoutedEvent routedEvent)
at System.Windows.BroadcastEventHelper.BroadcastLoadedEvent(Object root)
at MS.Internal.LoadedOrUnloadedOperation.DoWork()
at System.Windows.Media.MediaContext.FireLoadedPendingCallbacks()
at System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks()
at System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget)
at System.Windows.Media.MediaContext.RenderMessageHandler(Object resizedCompositionTarget)
at System.Windows.Media.MediaContext.Resize(ICompositionTarget resizedCompositionTarget)
at System.Windows.Interop.HwndTarget.OnResize()
at System.Windows.Interop.HwndTarget.HandleMessage(WindowMessage msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Interop.HwndSource.HwndTargetFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)