LP900 filters sharply block light below 900nm while allowing longer wavelengths to pass. This would be the filter of choice when viewing reflected 915nm laser diode light. These filters can also be used in infrared digital photography, as detector windows and in various scientific and forensic applications. For example, images of blood stains or gun shot residue on dark-colored fabrics or denim can often be enhanced by causing the fabric to appear white or comparatively much lighter when using a LP900 filter over the lens of a camera that has had its IR blocking filter removed.