What are Negative Paintings?

My method is best explained visually; 

 I start with a regular photo.

I start with a regular photo.

 I digitally invert the colors to get a negative, at this point the picture resembles a film negative.

I digitally invert the colors to get a negative, at this point the picture resembles a film negative.

 I simply paint what I see on this inverted photo. Sometimes I even do it "blind" and guess what the inverted colors would be. Helps to have a color wheel memorized.  

I simply paint what I see on this inverted photo. Sometimes I even do it "blind" and guess what the inverted colors would be. Helps to have a color wheel memorized.  

 This is the final print. I photograph the painting and then invert the colors again to get this. 

This is the final print. I photograph the painting and then invert the colors again to get this.