Color Value Tool?
I am planning on making a version of the Thousand Pyramids quilt. This scrappy version relies heavily on placing your fabrics by value: Light, Med Light, Med, Med Dark & Dark. So now I have a pile of scraps that I need to sort by value. I've looked into purchasing one of those red filters, but just today I saw that you can't use just a red filter you need a green one too? I also remember folks talking about using B&W photos. Don't have a camera that shoots B&W. Can I pull a photo into photoshop & switch the colors?
Any tips would be great!