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nikkadim
July 5, 2013, 18:00:34
Hello,

Camera: DMM 42BUC03-ML
Firmware version: 135

I have noticed that from second frame on high freq (~24Hz) I've got images much darker that first one. Intensity difference ~40%. Decreasing frequency down to 12Hz allow achieve difference (between first and next images) in 6%. But it is still unacceptable!


Example: http://nikkadim.com/pack.zip (~2MB)

Stefan Geissler
July 8, 2013, 10:23:53
Thank you for the image. Before I start reproducing this on my own, please let me know the settings for gain and exposure.

nikkadim
July 8, 2013, 13:53:24
Thank you for the image. Before I start reproducing this on my own, please let me know the settings for gain and exposure.

With this freq, this cappened with exposure = 2ms, minimal gain, and Y800@1280*960

Thank you.

nikkadim
July 8, 2013, 22:57:00
I think I have found the reason - trigger pulse width. I don't remember any suggestions in official TIS documents or FAQ's, but it seems that pulse width should be much less then exposure time, not matter what frequency you gonna use. I have decreases pulse width from 20 ms to 0.5 ms and I've got a good result! And they are repeatable.
Can you explain this?

Stefan Geissler
July 9, 2013, 08:58:16
Hmm, that is stunning. I thought, the pulse length does not matter at all, since I was told, the camera reacts on the rising or falling edge only. I will keep this in mind. Thank you very much for your patience and good work.