aquired picture gets darker

[NIRichard]

Hello,

i've created a labview program with NI Vision.

I acquire a picture with a webcam and then check it if there is a cube and get the position of the cube.

The problem is each time i run the inspection the acquired picture gets darker.

I've got the same problem when i open the inspection with NI Vision.

The cable of the Webcam is about 1.5 meters long and i enlarged it with another 2 meter long cable to an total length of 3.5 meters, earlier i was using a cable with an total length of 4.5 meters with the same problem.

When i use other software(vlc player) to just acquire a picture the picture dont change.

I've attached a picture that shows the problem and the NI Vision inspection that i created.

I'am using this webcam: ELP 1080P 2MP 30fps JPEG 1920 x 1080 Full HD Mini USB Box CMOS Kamera mit 2.8-12mm Vario Objektiv

[majoris · Accepted solution]

I can't open your files but the main thing would just be to make sure that the properties for exposure time, brightness, gamma and what not are not set to Auto as then they might change from acquisition to acquisition. You should set all exposure related parameters to Manual and choose values that are reasonable given the exposure you are trying to take.

[NIRichard]

The Exposure time and the White balance where on auto(in the Acquire image step), i switched them to manual and now it works!