This formula was suggested to us by Mr. William Troop who in experiments with Windisch Pyrocatechin developer reversed the proportions of sodium sulfite and catechol (pyrocatechin). The resulting super compensating developer works well with Kodak Technical Pan Film and yields negatives that can record a range of 7-10 stops. For use with this developer, Technical Pan film should be exposed somewhere between 32-64 ASA. Catechol Pyrocatechin is a tanning developer, stains (actually fogs) the negative and also hardens the emulsion protecting it from reticulation. The negatives, however, have a brown color and look dark, even at the edges. This is the normal appearance of negatives developed in catechol. Modified Windisch Film Developer was formulated for use on Technical Pan Film and it may not be satisfactory with other films. If you wish to use this developer on films other than Technical Pan, we recommend that you first test it with scrap film.
CHEMICAL SAFETY
All chemicals are dangerous and must be treated with respect. Please read
the warning on each package. There are two chemicals in this kit that need
special attention: catechol (pyrocatechin)
and Sodium hydroxide.
Catechol has a high vapor pressure and it is a phenol. The high vapor pressure means that the solid catechol evaporates readily. When you open a bottle of catechol, you can smell it. Always store solid catechol in a tightly capped glass container. When mixing a solution containing catechol, work in a well ventilated area. When catechol is a solution its vapor pressure is not a problem.
The fact that catechol is a phenol means that it is a corrosive and has the potential to cause skin burns. If you should spill a solution of catechol, wash the area (or skin) with soap and water. Use tongs or rubber gloves whenever possible.
Sodium hydroxide, as a solid or in solution, is a dangerous chemical. It is corrosive and will cause a chemical burn. Its action is insidious because the burn occurs without pain. When working with sodium hydroxide, wash your hands frequently without using soap. If you detect a soapy feeling while washing, sodium hydroxide is present. In such a case wash thoroughly with soap and water.
The beads or pellets of solid sodium hydroxide are easily spilled during solution preparation. If spillage occurs outside a sink, all of the spilled solid must be cleaned up. Use a damp disposable towel. If the solid is not cleaned up, it will absorb moisture from the air and form a puddle of very caustic hydroxide that will not evaporate.
Proper technique for preparing sodium hydroxide solutions is described in the Mixing Section of these instructions. We strongly urge you to wear both safety glasses and rubber gloves when working with solid sodium hydroxide and its solutions.
MIXING THE STOCK SOLUTIONS
You will need a brown bottle and plastic bottle (or other suitable
container) each with a 1-liter capacity. To prepare the
sodium hydroxide
solution, you will also need a 2-liter plastic mixing container, a plastic
funnel, and plastic spoon. Two stock solutions are prepared. The working
solution is mixed just prior to use.
SOLUTION A
| Chemical | Amount | Units |
|---|---|---|
| Water (100°F/38°C) | 750 | ml |
| Sodium sulfite (dessic) | 80 | g |
| Catechol (pyrocatechin) | 12.5 | g |
| Cold water to make | 1000 | ml |
Prepare this solution in a well ventilated area. Place the water in a mixing container and add the sodium sulfite. Stir the solution until the solid has gone into solution. Add the catechol and, again, stir the solution to dissolve the solid. After the catechol has dissolved, add cold water to bring the final volume up to 1000 ml. Stir the solution to ensure it is homogeneous then transfer it to a storage container.
SOLUTION B
| Chemical | Amount | Units |
|---|---|---|
| Sodium Hydroxide | 100 | g |
| Cold water (61°F/16°C) | 800 | ml |
| Cold water to make | 1000 | ml |
This solution must be prepared in a sink AND in a well ventilated area. Place a dry 2-liter wide mouth plastic mixing container in sink and place the solid sodium hydroxide in the container. Measure 800 m1 of cold water and carefully add the water to the container. Stir the mixture with a large plastic spoon until the solid has gone into solution. Stir constantly and avoid splashing the solution.
When sodium hydroxide goes into solution, considerable heat is generated. If your water was not cold enough, the solution may star to steam. If this should occur, add some ice to cool the solution. DO NOT BREATH THE VAPOR. It contains entrapped Sodium hydroxide. If the Solution starts to steam and you cannot cool it, leave the room and let it cool off by itself.
After the solid has gone into solution, let the solution stand until it reaches room temperature. Using a plastic funnel transfer the sodium hydroxide solution to its plastic storage container. The transfer should be carried out in a sink. Add sufficient cold water to bring the final volume up to 1000 ml.
Before any of the mixing equipment leaves the sink, rinse all utensils with cold water until you are positive no residual sodium hydroxide remains. Be sure to wash the outside of the storage container before removing it from the sink.
SHELF LIFE
Stock Solution A has a shelf life of about 6 months. Stock Solution
B, when exposed to the air, will absorb atmospheric carbon dioxide and lose
its potency. Depending upon the frequency exposure, the actual shelf life can
be considered to be from 1 to 2 months.
USAGE
WORKING SOLUTION
| Solution | Amount | Units |
|---|---|---|
| Stock Solution A | 25 | ml |
| Stock Solution B | 15 | ml |
| Cold water to make | 1000 | ml |
The Working Solution is used as a one-shot developer; discard after use.
DEVELOPING SEQUENCE
Technical pan Film has a very thin emulsion on a plastic base. Therefore,
the fixing and wash times are shorter than normal. With careful processing,
the negatives will be very permanent.
A typical developing sequence at 20°C/68°F for Kodak Technical Pan Film is:
| Develop | 10-15 minutes with agitation every other 20 seconds |
| Stop | 30 Seconds |
| Fix | 2-3 minutes with Formulary Rapid Fixer (Cat. No. 03-0142) |
| Wash | 30 seconds |
| Clear | 1 minute using Formulary Hypo Clear Agent (Cat. No. 03-0165) |
| Rinse | 2 minutes |
REFERENCE
Modified Windisch Catechol Film Developer,
Kit No. 01-0105,
Photographers’ Formulary (800-922-5255).