Exposing and Processing Bluefire® Police™ high-resolution surveillance film with Bluefire HR™ developer.
Bluefire Police is an extremely high resolution panchromatic (black and white) film of a type which is generally only available to security and documentation professionals. It is unlike general-purpose films in many ways and, when correctly exposed and developed, can be enlarged to beyond the resolution limits of even the finest commercially-available lenses. Even at extreme magnification (for example, a 35mm negative enlarged to 5' wide and 4' high) its grain structure remains inconspicuous, and any image degradation present will be due to lens resolution.
Bluefire Police yields extremely high contrast images when processed with ordinary photographic developers. For that reason, when it is sold for pictorial or surveillance use, you should develop it in Bluefire HR, an extremely soft-working, ultra-fine-grain developer formulated especially for use with this type of film.
Bluefire Police film developed in Bluefire HR developer gives high-quality pictorial images with a very long gray scale when exposed at EI 80 and processed as follows:
1. Make up a working solution of developer. Add one part of Bluefire HR concentrate to approximately 16 parts of water (15ml of concentrate to 235 ml of water is a convenient amount, sufficient to process one 35mm 36-exposure roll of film). The working solution will deteriorate if stored for longer than about a day. Mix it fresh before each use, use it only once, and discard the used developer. An opened bottle of Bluefire HR concentrate has limited life and should be used before it begins to darken and turn red.
2. Develop your film in the working solution at 20°C for 12 minutes (continuous agitation) or 16 minutes (compensating agitation).
For consistency from roll to roll, use continuous gentle agitation. A Jobo rotary processor or equivalent is recommended for consistency. Manually rolling a processing tank back and forth along a tabletop will yield acceptable results. Roll it at the rate of about two feet (about 50-60 cm) in about two seconds, with about one or two seconds between rolls. At the end of 12 minutes, drain the tank.
For the best image, use "compensating" agitation. Agitate gently and continuously for 30 seconds after filling the tank. Then, every 30 seconds, give the tank a gentle up and down shake for about 5 seconds. After three minutes have lapsed, allow the tank to sit undisturbed for three minutes between 5-second agitations. At the end of 16 minutes, drain the tank.
3. Rinse the film in fresh water, by filling the tank with water and agitating for 30 seconds, then drain. Do this twice - fill it again and agitate for another 30 seconds, and then drain. Alternately, any ordinary acid stop bath can be used.
4. Fix and wash normally. Do not wipe the film or use forced air — let it dry while hanging. Use a wetting agent and dry the film in an area kept scrupulously free of dust. Because its emulsion is so thin, it dries very quickly.
Click here to view an extreme enlargement of a truly grainless subminiature photograph made with Bluefire Police surveillance film processed in Bluefire HR developer.
Click here to see a discussion of the difference between High Resolution Film and High Definition Film.
Click here to download exposure and processing instructions in the form of a PDF file (requires Adobe Acrobat Reader).
*"Bluefire" is a trademark and trading style of Adox Fotowerke, Inc., identifying a line of photographic film and developer products.