Hoya Filter R72 Infrared 55mmModel: 20255
This item is no longer manufactured.
R72 filters are for when you want to do true black-and-white infra-red photography. They are extremely dark (much darker than a Red 25A filter), letting only infra-red radiation of 720 nanometers or above reach the infra-red film. Since an R72 is so dark, it usually requires longer exposure times, so we recommend using a tripod in conjunction with this filter.