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Teststand handling Vision VI differently

Hi, I am trying to acquire a single image and analyze it on Teststand. I created a VI to get an image from a USB camera. The VI runs fine and the image is good for every run. However, when I run it through TS, the image acquired gets progressively darker and darker until I can barely see the image. 


Uploading the VI. Any idea why TS is not handling the VI similar to standalone VI execution ?

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When you call a VI from TestStand it should work same as in LabVIEW.


You can try the following to understand why it is happening :


Make your LabVIEW adapter setting to development.

Step into your LV code from TestStand.

Do the same from within LV environment also.

Check what is differently happening wrt running from LabVIEW only against stepping into LabVIEW from TestStand.


Hope this helps.




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Figured out the problem. The cheap camera shutter and internal image buffer was not working in sync thereby retaining a few image frames of varying brightness. Had to replace the camera with a better one and now it's working as expected. 


However, I also observed a slight difference in the way LV runs vision VI independent vs on a TS seq. 

If you generate a vision VI using the vision assistant, the template loading while loop has a first call icon connected to an OR gate. 

Everytime you run the VI independently, the first call boolean o/p stays TRUE.

On a TS seq after the first complete seq run, if you continue with the second run, this boolean outputs FALSE (which may make sense) but it throws the whole template image loading for a pattern match out of whack.  


Anyways, problem solved! 

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