why the acquire image will twinkling in the channel 1,2,3??

[Gary Liang]

I have 3 caremas(B&W Panasonic) and a PCI 1409 card and Imaq-A6822.
I want to acquire images from 3 caremas.
when I run the sample program "scan 1408" ,
the channel0 image display normal,
but the channel1,2 images are twinkling
and the image is divided into 4 pieces.
And I modified the program ,
let the 3 acquire images display in 3 different canvas.
The channel0 is ok ,
but the others acquire images are also twinkling
and the image is also divided into 4 pieces .
what is the matter??
is it the synchronous problem?

[BruceAmmons]

Gary,

I think it is a synchronization problem.

Try just acquiring video from channel 1, and everything should look fine. Same with channel 2. It is only when you cycle between them that you will have problems.

You need to have the cameras all start taking a picture at the same time, so that when the board switches between cameras they will all be starting a new image.

All cameras are different, but read the manual and see if you can figure out how to use the same Vsync and Hsync signals for each camera. You might be able to output the signals from camera 0 and use them as inputs on camera 1 and 2.

Bruce

[Gary Liang]

Thank you for Bruce Ammons's answer first.
I also think it is a synchronization problem.
But I have tried just acquiring a video from one channel. The problem is just acquiring the channel 0,
acquire image is ok, just acquiring the channel 1 or channel 2 or channel 3, the problem of image flicker and be divided into four pieces is still go on .
I want to know how to synchronization the signal.
And the cameras I have are panasonic BP330 B&W caremas. There are just two BNC connectors on the carema,one is video out ,another is Genlock .what is the function of Genlock BNC connector?Is there any help for solve the problem.
I also needn't to take the pictures at the exactly same time,it allow a little delay ,for the pictures I want to take is the still object
.
Thank you for you help and waiting for your reply!!!

[BruceAmmons]

Gary,

I'm not sure why the other cameras won't work. Here are a few things I would try:

- Use Snap instead of Grab, and see if you can get a good image from each camera. If so, this might solve your problem as long as you are not in a hurry.

- Swap the positions of the cameras, and make sure it isn't a camera issue.

- Disconnect the unused cameras while testing. For example, when trying to acquire from Camera 2, disconnect the other cameras.

Hopefully this will help you identify the problem.

I don't know any details about the Panasonic camera. I would guess that the Genlock input would be used to synchronize them, but I don't know the details of how to do it.

Bruce

[BruceAmmons]

Gary,

Another thought - do all your testing in MAX until you have a good image from all the cameras. This eliminates your program as a source of the problem.

Bruce

[Gary Liang]

Thank you for your big help.
I have solved the problem now.
I do nothing but I added another cable from CSYNCOUT to the GENLOCK BNC connector of the channel 1 camera.
That is to say CSYNCOUT can send a synhronization signal to the camera of channel 1. Two camaras of channel 0 and 1 can aquire image now .
But to the third camera of channel 2, I make a cable myself for it . The cable have 3 BNC connects. One is from CSYNCOUT , the other two are to the cameras of channel 1 and 2 (GENLOCK BNC connectors of the camera).So the problem is disappear now.
I think this method is not bad .
Thank you for Bruce Ammons's big help!!!