Jurassic park, once more

Thanks to Paul, I tried new tricks on PicMonkey, and I found out I can use color picker on sepia effect to choose any color I want. or almost any color... Only problem is there's no color chart available for the picker on the PicMonkey window. So, I can choose only colors seen on the view. I guess I could include a color chart into the image, first "reveal" it by "painting" on it, and then choose the color I wnat ;-)