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fmatassoni
March 12, 2015, 09:27:49
Hello, i have a little problem to synchronize the program flow with the time needed to the camera to receive and elaborate the instructions given. I have a DFK Z12GP031 model camera linked with a GigE card. Is there a way to know, after i sended a set property value command, when the camera have done to elaborate it? Because sometimes, when i try to set the zoom factor and immediately after take a picture, the picture i have taken is in the middle of the movement of the zoom so the result is awful. I try to set some delay beetwen the set property instruction and the grab image but it is completely arbitrary and i have the fear that cannot guarantee me that it will work all the time.

Every help in this problem would be very appreciated.

Thank you, Francesco.

Stefan Geissler
March 16, 2015, 11:37:41
Dear Francesco

Unfortunately we can not predict, when the lens has finished to move. Therefore, you can only wait a certain for this mechanical movements.

There is one exception at auto focus. The driver exposes the "OnePushRunning" switch property for focus. It is true, while the auto focus runs and false, when it ends.

Stefan Geissler
March 16, 2015, 11:37:41
Dear Francesco

Unfortunately we can not predict, when the lens has finished to move. Therefore, you can only wait a certain for this mechanical movements.

There is one exception at auto focus. The driver exposes the "OnePushRunning" switch property for focus. It is true, while the auto focus runs and false, when it ends.

fmatassoni
March 18, 2015, 15:06:50
Dear Francesco

Unfortunately we can not predict, when the lens has finished to move. Therefore, you can only wait a certain for this mechanical movements.

There is one exception at auto focus. The driver exposes the "OnePushRunning" switch property for focus. It is true, while the auto focus runs and false, when it ends.

Dear Stefan,

thank you for your reply. Can we make the same statement about changing the exposure value?

Stefan Geissler
March 18, 2015, 15:24:25
A new exposure value is set, after a frame has been delivered. While a frame is in "work", exposure can not be changed. It is pending, until a frame has finished.

fmatassoni
March 18, 2015, 15:56:05
A new exposure value is set, after a frame has been delivered. While a frame is in "work", exposure can not be changed. It is pending, until a frame has finished.

So if i delete the first frame captured, after sending a Set Exposition command, and taking the second one as the good one can i be sure that the frame has the correct exposition?

I try to explain it in a better way:

1) Sending Set Exposition command
2) Capture one frame (with Grab Image VI) and delete it
3) Capture a second frame
4) Elaborate the second frame

Thank you for your time Stefan.

Stefan Geissler
March 18, 2015, 17:06:12
Not completely right. You can set an exposure time also, while the live video is not running.

However simply try it out and see what happens.