Infra Red on Film or Digital
The weird world of IR can be captured on film or digitally but, since IR light is outside the normal visible range, each requires some specialist equipment and planning.
All film types and digital sensors record IR ‘light’ but to different degrees. Digital sensors are so sensitive that manufacturers are forced to cover the sensor with a hot mirror filter to remove what would otherwise interfere with normal results. A digital camera can be converted to remove this filter allowing for much faster shooting speeds. However, by using a IR filter, ie one that only lets through IR light, it is possible to take photographs with conventional digital or film cameras: photographs that have an otherworldly appearance.
An IR filter at first glance appears to be black, but a bright light will reveal it is a dark cherry red that removes blue and green and most red from a scene. Having effectively stripped away most of the light a longer exposure becomes necessary and a tripod almost essential. Typically for film a 200asa rated IR film can, with the filter in place’ be rated as 25asa. A hand held light meter, set at 25asa is useful to avoid having to remove the filer from the lens to take meter readings.
In the past Kodak manufactured a colour IR film, apparently for military use, but most IR photography today is black & white. Happily Rollei, Ilford and Adox have reintroduced IR biased black & white film, though each must be used with a ‘black’ filter: each film has extended spectral and so without a filter, will record all tones and the results will be quite ordinary!
Digital photographers using an IR filter can make either colour or BW images and let the camera do the hard work of exposure reading though some fine tuning on manual may be required. The exposure time is likely to be longer than can be hand held, which is why a tripod is needed for times of anything from 1/30th sec to several minutes.
At the Darkroom UK Ltd we see a reasonable amount of IR film for processing both over the counter and by post. It is important to store any film in light-tight packaging but particular care is needed for IR film. It is not ambient heat that can cause the problem but scattered IR light that can sneak around the edges of containers that are designed for normal visible light.
Label the contents as IR FILM and use the original black film-pot for 35mm film. For 120 film, a layer of metal baking foil wrapped around the roll is ideal: this is useful if you find your normal film is not wound up tightly as it will block any light from reaching the emulsion. Finally, please, PLEASE tell us what type of film it is: we cannot guess what might be inside a silver-wrapped package and we can’t read in the dark either!
How can we help? We can of course process any BW film from 35mm to 8"x10" , often same day and adjust development to suit the film type and exposure. On the printing side we can make traditional BW hand prints on either resin-coated or fiber based paper.
If you've gone the digital route then you can upload images via the online shop for either collection or return by post. Whichever route you've taken give a call if you'd like to interpret your image in a particular style.
For more info try these links:
And great examples of what is possible
The Darkroom UK Ltd