Rollei Ortho 25 is an orthochromatic black-and-white negative film optimized for technical, scientific, and half-tone work, as well as creative and pictorial applications. Characterized by extremely high sharpness and resolving power, this unique film also features an impressively fine grain structure and is also well-suited to reversal processing for black and white transparencies.
Ortho 25 has a nominal sensitivity of ISO 25/15° and a high-sensitivity reserve of two stops for greater flexibility when shooting. Its spectral sensitivity ranges from 380-610nm and is suitable for photographing in either daylight or tungsten-lit conditions. The film's polyester base has been tested to an LE-500 (life expectancy 500 years) archival rating and also features anti-curling and anti-static coatings, as well as a special coating to promote smooth film transportation within the camera. Additionally, this clear base is particularly well-suited to scanning applications.