One caution regarding using Firewire cameras.  They consume a lot of
computer power, just transferring the image to memory.  This depends on the
size and kind of image the camera is delivering.  So, you may want to
investigate whether or not the computers you will be using can handle
firewire adequately and still have enough power left over for running
LabVIEW, etc.

I have been testing 2 Q Imaging firewire cameras (monochrome, 16 bit word,
and a resolution of about 1280 x 1024).  The image rate is about 15
frames/sec.  Just regularly acquiring the image in LabVIEW consumes 30% -60%
of my CPU (1.2 GHz).  I tried using 2 cameras at the same time and my
machine just stops working.

I am also using a Sony DFW-SX900 color camera (1280 x 96 at 7.5 frames/sec).
This camera, with LabVIEW running consumes 80% of the cpu.  Periodically, it
will move up to 100% and the computer will freeze for several seconds.

If you run at reduced image sizes, it will make a dramatic difference in the
amount of cpu time being consumed.

Some firewire cards do not work as efficiently as others.  For the best
performance, use a dedicated, 1394 only card.  Do not use a combination
USB2/Firewire card.  And, be sure to use a 1394 card that is OHCI compliant
and uses the Texas Instruments chip set.

At the end, I had to purchase a new computer with; CPU 3.0 GHz, fast FSB
(400 MHz) and serial ATA hard drive.  This eliminated the problems.  My
client had to do the same thing in order to be able to use 2 cameras on his
project.  The bottom line is: if you want to use 1394 cameras with 1+MB
image sizes, you need the fastest computer you can get.

Lewis Drake
Process Automation Corporation
Belle Mead, NJ
908 359-1011
www.processauto.com




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