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Single camera to use two times with different exposure

Dear Team,

 

I am using single camera two times with different exposure value in my VBAI program.

 

Sometime I am getting an image that has been acquired prior to the exposure time change.

So. could you please suggest how to overcome this issue.

Because in my program I am facing this issue and some time there are 2-3 % of these prior images.

 

Thanks and Regards,

JN

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Message 1 of 4
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In my project, I would add  a "delay" function about 500ms between changing exposure time and acquring image.

 

2020-09-04_101234.png

Message 2 of 4
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I think you will need to resolve your issue differently.

Issue is that on any industrial camera changing mode is not strictly define in time.

Some time it takes longer and some time it is shorter.

Hardware solution:

You can control the camera exposure from I/O (most cameras). For example you can create a pulse train that has one long pulse and one short pulse.

Camera is all the time in the same mode. Exposure is controlled externally

Software solution:

After you change the exposure you need to read the exposure back from the camera. You need to repeat that until exposure time is changed.

 

Best - Amit

 

Amit Shachaf
Message 3 of 4
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Can't speak specifically to VBAI but when I do this with Vision Development Module I have to stop the camera, write the new exposure value with a property node and then start the camera. Maybe that gives you a clue.

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