The Kodak Rapid Selenium Toner produces several cool chocolate-brown hues with warm-tone papers, purplish brown tones with neutral-tone papers and very little or no change with cold-tone papers. Use the 1:20 dilution for print protection. To increase shadow contrast and maximum density with a minimum tone change, use a 1:20 or 1:40 dilution. You can also use this toner with black-and-white films. It converts the silver image to silver selenide.