I stumbled on this on another website and it was just too cool not to share. Check this out. How many colors do you see?
You think you see, pink, blue, orange and green right?
The blue and the green are really the same color! If you take it into photoshop you'll see I'm not kidding.
Here's the colors the swirl is really made of.
So other than, gee this is a cool trick what does it have to do with needlepoint. Visual blending! Stitch with one color on a different color canvas. Do they still look like the original pure colors? Not always they interact with each other.
In this case the pink is making the green look blue. How cool is that?