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Image acquisition using DAQmx

I am currently using the DAQmx with IMAQ, to read in a voltage from a sensor which scans an image and saves the data in an array, an then use IMAQ to display the image, although all i get is a black image at all times, even though the data is being read in.
 
 
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Hi c lees,
 
What are the values you get back from your DAQmx task? (the range)
You'll find that the image probably isn't actually actually completely black.  But the image (when set at 8 bits) has 255 levels. (255 is bright white) so if your values are between 0 and 10V then the image will appear very dark.
 
Maybe try adding a multiplication factor to the data array before you convert to image?  (say.. 25.5? for a 0-10V image)
If the range is between -10 and +10, you will need to offset by 10V and then multiply by 12.25.
 
Does that help at all?
 
Thanx
 
AdamB
Applications Engineering Team Leader | National Instruments | UK & Ireland
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Hi c lees,

Did you manage to solve your problem in the end?

Hopefully you did, but if not I'd be happt to help further if you post back again.

 

Thanx

AdamB

Applications Engineering Team Leader | National Instruments | UK & Ireland
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Hi,

Thanks for your help.  I added in a mutliplier and there is some sort of an image coming through now, i also did not have any timing for taking in the samples and i think thats what was causing  the problem as well.

Thanks

C Lees
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