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How do you force a blank screen as default for an IMAQ image?

I have already tried several things with partial success.
 
I created a default blank image and used the "Data Operations" > Make current value default.
OK... I do occasionally get the blank image.
 
However, for some sytrange reason, once the vi (or sub vi) is called, the next time it is called, although processing an Invoke Node to re-initialize to default, the "residue" from the previous image is displayed...
 
To put it bluntly, all the conventional methods to force an initialized value for an indicator seem to escape the IMAQ imagge display.
 
How can we either force a blank (or balck) image at the start of a sub-vi?
 
Thanks
 
RayR
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JLV, 
I understand that you didn't use Imaq dispose before exiting your VI. So the Image buffer content is still there, and you have to actually write to it when you re-run the vi if you want it to be updated.
Since you probably used Imaq create, the simplest thing is to write as soon as possible to a local of your display, as in the attached diagram. 🙂
 

Message Edité par chilly charly le 09-19-2006 06:09 AM

Chilly Charly    (aka CC)

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Thanks CC,

I noticed that you were into IMAQs by reading some of your earlier posts (June  July)?

IMAQ dispose...  yep.. it rings a bell..  I will check it out.

Thanks buddy!

RayR

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Thanks Charles,

It worked with the Local Variable.

I guess my days of preaching the use of Property Nodes caugth up to me in this instance. 

RayR

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