Hello,
I'm not exactly sure what the NI rep meant by "internal" synchronization. When ever I use the phrase "internally synchronized" I am referring to the camera generating its own timing signals. With multiple cameras, this would mean that each camera generates its own internal clock signals. This would mean that they are not synchronized to each other.
If you are using a single multi-channel IMAQ board, you could programmatically switch between two non-synchronized cameras. But only one image is going to be acquired at a time (since the channels are multiplexed). In addition, switching between cameras generally takes a couple frames before the next image is acquired.
Genlocking is typically the method I recommend for synchronizing cameras. With this technique, both cameras would use the same timing signals. If you are using multiple IMAQ boards, then you could trigger each board at the same time to acquire simultaneous images. If the cameras are not genlocked, then there will most likely still be a small difference in the exact time that the image is acquired (since the timing signals would be different).
Best Regards,
Jesse D.
Applications Engineering
National Instruments
