Store value on button click for background subtraction

[dexeqex]

Hi Folks,

I'm very new to labview so hopefully you'll bear with me.

I'm acquiring intensity data from a camera continuously in a while loop, turning it into a 1024x1 array, and displaying it in a graph.  I need a way to subtract the background signal from the camera and display whatever's left.  In a written programming language it would go something like:

bg = 1024 zeros

if(Button pushed)

    bg = current frame

else

    do nothing

new_sig = current frame - bg

I've tried case structures, global variables, and shift registers, but none of those seem to work.  I'm sort of at the end of my rope.  Let me know if there's any other info I can provide.

Thanks for your help!

[crossrulz · Accepted solution]

Something like this?

[dexeqex]

Yep, that did it.  Thank you so much!  I knew it would be something simple like that.  I'm still slogging up the steep part of the Labview learning curve.