Inverted test?! Why? HELP!

[mwah_xx]

Ok so I found a pregnancy test checker app which I’ve been having fun with but I wondered what the idea behind inverting was?

My test looked pretty white to me but I inverted it anyway to play around with it and no idea what it does!!

 

[ClairAye]

When it inverts the colours if there is a line, you can sometimes more easily see green on a dark background v light pink on white.

 

[phantomfaery1]

I can definatly see a line on the original pic

 

[Bevziibubble]

I see something faint

 

[amytrisha]

Problem with inverting is it’ll show up a line even if there’s no colour to it, so evaps and Just the indent line also.

Good luck!