NI-IMAQ Grab Smoothness

[J Gudenkauf]

When using the MAX program and all the others that I have avaiable for grabbing an image from the NI-IMAQ 1424 board the image that is displayed is fragmented. Meaning that the image is shifted over(up-down and side to side) and the image is wrapped so that the entire image is there. However, when the snap function is used the image is displayed properly. What could be the possible problems and solutions (if any).

JAG

[JR_A.]

What camera are you using? Are you running the camera in 'free run' mode or are you triggering it? It would be a good idea to make sure that you have the latest version of NI-IMAQ which at this time is 2.5.1 and then there is an updatde to 2.5.3. Those can be found at IMAQ Downloads. Also, make sure that you have the latest version of the camera file for your camera. Camera Advisor 

Cheers,

JR A.
Application Engineer
National Instruments

[bleen]

I am also having this problem (as well as some others). I am using the PCI-1424 and have updated the IMAQ drivers to 2.5.1 (w/2.5.3 update) together with a sensors unlimited SU320-1.7RT camera in free running mode (although there are similar problems with the tirggerable version of this camera). The grab problem can be fixed by changing a constant in the LL Grab in IMAQ Vision Display.vi. Changing the memory location from system to onboard makes the grab run smoothly (at least in my setup).
The problem i have after this, is that the ll sequence doesn't work either and changing to onboard memory is not a fix. The symptoms seem related in that only the first frame and half of the second are new (when grabbing ~10 frames). All the others are holdover from previous aq
uisitions. Ideas?

[J Gudenkauf]

I have already set the memory location to the board and updated to 2.5.3. During my tests I decided to try the HL and LL Grab example for C and they worked fine, however the sample changes the ROI and I need the whole picture. When I kept the cameras full picture, with these examples, and I noticed that the frames per second being transferred was about 4, when it should have been 7.5 fps, but when the ROI was changed it was 7.5. Any thoughts on how to fix this?

JAG