Light Theatrics offers a great method for blocking out unwanted light.
Commando Cloth is an economical choice for all of your masking fabric requirements. This flame retardant, cotton fabric has a multitude of applications due to its brushed napped surface and light absorbing qualities. It has the look of heavier velour fabrics but without the actual weight or cost and is perfect for when you need to make quick masking drapes.
All prices are in USD.