Development of Kodak Techpan Black & White Film
Kodak Techpan film is perhaps one of the finest grain black and white films ever made when properly developed.
To use Techpan film for pictorial work you should develop the film in Kodak Technidol developer. This will give the film an effective ISO rating of 12. This is very slow but if you have the light or a good tripod it is well worth it. The grain is so small that it is basically invisible in the grain magnifier under the enlarger.
The following is my method for developing Techpan film in Technidol liquid developer. Other developers will change the effective ISO, contrast and grain structure of the film.
All chemicals are used at a temperature of 68 degrees F (20C).
- Mix Technidol Liquid developer in 10 ounces of water (instead of 8 as suggested)
- Presoak film for 2 minutes in plain water at 68F with some agitation.
- Spill out presoak, notice it will be black in color.
- Pour in developer and Develop for 6'30" agitate continuously for first 30 seconds, then 5 seconds every 30 seconds there after until time is up.
- Pour out developer, you can re-use it one more time. Only 2 rolls per mix. It will not keep for more then a few days so wait until you have 2 rolls to devlop so you don't waste it.
- Stop bath for 30 seconds.
- Fix in standard hardening fixer for 10 minutes. Agitation 5 seconds every 30.
- Wash for 1 hour in running water bath or use hypo clearing agent and wash for 30 minutes.
- Photoflo final rinse and dry
You will be amazed at the quality of the images, produce grainless 11x14 inch prints from 35mm film and larger from 120 or 4x5 film.
This film is a real unknown treasure, enjoy!
Note: Actual film speed was determined using a McBeth digital transmission densitometer. Measurement was based on a reading of .1 density over film base plus fog using Technidol developer. The use of any other developer will change the film speed, contrast gamma and grain structure. Developing time was empirically derived using a diffused light source printing at zone 8 as described in "The Zone VI Studio Handbook" by Fred Picker.