I would tape graph paper behind the glass, then quickly take a photo of the nasal condensate, count the pixels.hi,
When breathing against a glass, a shape of the air that comes out of the nasal cavity is left on that glass.
Usually those 2 shapes look a little different.
Is there a sensor to test the area that (the exhalation in this case) is left on the glass?
Is it related to the temperature?
Could an utrasonic or pressure sensor be used for that test?
I appreciate your help.