Dual Instances SGP for Piggy Back Setup



I seem to be having problems with using dual instances of SGP to run a piggy back scenario. I have a Moravian 16200 on the main scope and an ASI 1600MM Cool on the piggy back scope. I also run two robofocusers. I can’t seem to even get the program to launch for the second instance. This makes me wonder if this can be done. I have seen others posting that they can run dual instances and have even seen the developer remark that it can be done on other posts but for some reason I can’t even get the program to start up. Any settings I have to watch out for that would crash the second launch of SGP on the same computer? I am not even sure I can get a log on the failed launch. Maybe I can post a link to the screen shot? I guess first thing is are there any settings I need to check?


I do it all the time with no trouble, so I know it can be done. However, I think I have seen Jared say before that multiple instances of SGP are not officially supported. For some reason, I always get the Windows UAC prompt when I launch the second instance. So, it could be that your security settings are preventing the launch.



I thought you did Tim, but for some reason the second launch is bombing on me and I can’t even seem to get it to open correctly. Currently I am working with Maxim DL as the second camera and focus control. It works well with the ASI 1600 since day one. This solves the functionality problem for me, but I am just wondering why I can’t get two instances to launch correctly. Everything is ready for the ES 102mmED/ASI 1600 combo and the RC10 Moravian 16200 except for one adapter for the Moravian and getting SGP to launch with two applications.


I think the key is the UAC prompt. My security settings may be allowing the second instance to run with the UAC prompt. Your settings may be prohibiting it completely. You might try running the second instance as administrator. Either that, or loosen up your UAC security settings.

My guess is that the second instance wants to open the same log file as the first instance and that causes the UAC prompt. Next time I do it, I’ll have to check my SGP log to see if it is all screwy. I’ll bet it is.



Just to add - if you have your UAC settings set to “Never Notify” (the least secure setting) then Windows will simply refuse the action that throws the UAC notification. I’ll bet that’s what’s happening. You can prove this by running the second instance as administrator.

I’ll add that since this is an unsupported method, I have no idea what kind of things it can screw up. I have always been careful not to open the same profile in each instance, for example, for fear that it would corrupt the profile. Likewise, I never select the same equipment in each instance.



Most everything between the two instances is separated and shouldn’t cause issues. I can’t think of a reason you’d need to run one instance as Admin but maybe there is something that I’m not thinking of that is shared. The main thing that would be shared would be the system settings. It may cause a problem if you change those in one app. Then they’d likely get reflected in the other app as well. These settings are generally found in the “Options” area of SGP.



All I know is that I get a UAC prompt whenever I open the second instance. According to Wikipedia, the following events will throw a UAC prompt:

Running an Application as an Administrator
Changes to system-wide settings or to files in %SystemRoot% or %ProgramFiles%
Installing and uninstalling applications
Installing device drivers
Installing ActiveX controls
Changing settings for Windows Firewall
Changing UAC settings
Configuring Windows Update
Adding or removing user accounts
Changing a user’s account type
Configuring Parental Controls
Running Task Scheduler
Restoring backed-up system files
Viewing or changing another user’s folders and files
Running Disk Defragmenter
Running Registry Editor
Running the Windows Experience Index assessment

I figured that the bolded one was the only one that seemed plausible to me. At any rate, bigeastro should be able to get it to run if he gets his UAC settings sorted out.



I have been running 2 or 3 instances of SGP for over a year with no problems whatsoever. I have 3 scopes on the same mount and I have imaged on all three at once. Worked from the get go for me. Can’t think of anything else to try not already mentioned.


How are you taking care of dithering ?


I don’t dither. It is not necessary if you use cosmetic correction (PI’s term) when processing your images. If you are not familiar with this, it uses your master dark to eliminate all the hot and cold pixels. Works perfectly.
However, if you are doing really wide field imaging and plan to drizzle your data to improve your resolution, you will still need to dither.
The one issue you have to put up with is there is no coordination between the SGP instances so you generally end up with 1 or 2 bad images on the scopes that are not controlling the target selection. One instance does all the mount control, the others just take images. I set up all copies of SGP to image all targets in a set time frame which matches that of the control SGP.


Thanks you jmacon!

Clear skies.