Dear Dr. Thielicke,
I'm wondering if there is a way to reverse the sign of the v component of the velocity. In my plots the upward velocity has a negative sign and my advisor thinks that is counter-intuitive and I should change the sign to be negative downwards. Is there a way to easily do this? PIVlab is truly fantastic. Thank you.
one easy way to achieve this would be to change the order of your image data: When you correlate imageB.jpg with imageA.jpg (instead of ImageA.jpg with ImageB.jpg), then all your velocity components will be reversed.