Do You Need a Film for a Special Purpose?
Aside from Polaroid film, which contains developing chemicals in each picture, a
number of unusual film technologies exist.
■ High-contrast films produce only two tones: the clear film base and black,
without intermediate tones of gray.
■ Infrared films respond to infrared wavelengths that the human eye cannot
see. These are available in black and white and color.
■ Chromogenic black-and-white films, such as Ilford XP2, produce a dye image
rather than a silver one. They have excellent exposure latitude, which means
you can expose individual frames at different film speeds. Frames exposed at
about ISO 100 will have finer grain, but frames on the same roll of film can
be exposed at speeds as high as ISO 800 and still produce printable nega-
tives. This differs from conventional films, which require you to expose the
whole roll at a single film speed. Chromogenic film must be developed as if it
were a color negative (in Kodak’s C-41 chemistry or Ilford’s version of the
same process), which is available at your corner drugstore.Most of these cameras accept another type of roll film called 220, which has paper
only on the end; this reduces the thickness of the roll so that more film can be
wound on the spool and more exposures made.
Sheet films, or cutfilms, are designed for large-format cameras, such as 4×5-inch
and 8×10-inch cameras (also called view cameras). Sheet film is packaged 10 or more
sheets to a box. Some film must be loaded in film holders before use, although you
now can buy sheet film in disposable holders.34 ABSOLUTE BEGINNER’S GUIDE TODIGITAL PHOTOGRAPHY
WHAT ABOUT APS FILM?
Advanced Photo System (APS) films were released a short time before digital photography
took off. This red-headed stepchild of film is actually highly advanced. Every roll of APS film
contains a magnetic layer that records the format in which you want the print, the date,
frame number, and other data.