Ortho Film

11/01/12

What is ortho film? Ortho is short for orthochromatic, an early type of black and white negative film which was not sensitive to red light. A century ago it was the standard type of film. In the 1930's and 40's it was gradually superseded by panchromatic film, which was sensitive to all visible wavelengths of light. As it was not sensitive to red wavelengths, the old ortho film could be loaded into a camera or developed under a dark red safelight.

Many might be surprised to learn that it is still available. So why on earth would anyone want to use it? Two reasons: ortho film has a distinctive 'look' when printed. Skies tend to be lighter, but anything with blue in it takes on this different look. Of course, as it cannot 'read' red, reds come out as very dark or black. It can produce very atmospheric landscapes, and is a simply unique film for skin tone. Ortho does tend to emphasise any blemishes in the skin, and darken red lips, so needs to be used on perfect female skin, or on male subjects when texture and ruggedness is being emphasised. However, I cannot overestimate how impressive this film can be for portraits, if used carefully.

The second reason for using ortho is resolution. When manufacturers discovered that they could use dyes to sensitise ortho film to red, there was a trade-off. Panchromatic film, although it 'saw' all colours, suffered a fall-off in resolution. Resolution is the capacity of a film to resolve tiny detail, and ortho films are remarkable in their resolution, and dramatically out-perform modern panchromatic films in this respect. One 'downside' is that ortho films are slow, typically 25 iso. That sounds terribly old-fashioned to modern photographers - but I would invite them to go out on a bright day with a fast lens - and just see how easy it is to use handheld. You might be working at apertures of f2 -f4, but professional lenses perform well at fast speeds today, and if you do need a greater depth of field, use a tripod. You will discover that iso 25 ortho film shot in a 35mm slr will look like medium format! Shoot it on 5x4", and you might never want to use digital again!

For those who are considering commissioning monochrome imagery, ortho is well worth thinking about. Few photographers today will be familiar with it, but if you can find someone who understands the film, you can achieve a truly unique image with extraordinary detail. Photographers who are interested can do a google image search of ortho images: take a look at Karsh's wonderful ortho film portrait of the young Ernest Hemmingway. You will find that low-contrast subjects suit contrasty ortho film, and you will need to find a sympathetic lab or process yourself, being aware that these old emulsions are very delicate when wet. Of course, if you are seeking to capture a 19th century look, ortho will do the job like nothing else. Also - if you are new to large format, and don't fancy loading film holders in the dark, you can buy a second hand dark red safelight and load and process film like they did in the past!

Orthochromatic film still has a place today, and photographers need to support it; it's only just still available. Ilford make it in 5x4" and sell it as specialist copy film (Ortho Plus), and Adox produce an iso 25 true ortho film in 35mm. which can be obtained in the UK at AG Photographic. Like much in the analogue photography world, digital capture offers no equivalent, and if photographers do not support these specialist films and maintain a demand, these unique tools will disappear for ever. Once gone, no one will find them economical to re-manufacture. These tools enhance our creativity - and that should be what photography is about.