A see through red plastic will work fine. I use a big piece to see contrast in all my fabric selections for a quilt. Many people put the plastic to their eyes but I was taught to hold it about arm length and look through it. You can use see- through green to see contrast in reds. It really works. Many times I think two fabrics are contrasting and find out they have the same value. It's great for log cabin fabrics.
Last edited by BellaBoo; 03-18-2013 at 11:56 AM.