Processing Notes

There are a number of factors that will affect your development time. Please keep the following in mind.

AGITATION. The longer and more aggressively you agitate the film in the developer, the shorter your development time will be. Consistency is very important. My agitation plan for roll film is as follows:

• Constant agitation for the first thirty seconds.

• Rest for thirty seconds.

• Agitate for five seconds for every thirty seconds up to the total development time.

(See A Primer on Basic Photography.)

DILUTION OF THE DEVELOPER. It's extremely important that you accurately measure your chemistry every time you process your film. Changing the dilution has a dramatic effect on the contrast of your negatives. Very dilute developers reduce negative contrast. Higher concentrations increase contrast. (See Appendix K.)

Note: Jobo processors automate the agitation process by giving the film constant agitation. For this reason your Normal Development times will be approximately 15% shorter when using these processors.

TEMPERATURE. Once you establish a working temperature for your chemistry, make sure that you don't stray from this standard by more than one degree. TANK VS. TRAY DEVELOPMENT. This applies to sheet film users only.

With the tray method, the individual sheets of film are agitated continuously by a hand in a tray of developer. Use a tray that is large enough to allow easy handling of the film. Trays with flat unchanneled bottoms aren't recommended. This method uses less developer than the tank method, and because the agitation is constant, the processing times are shorter. Presoaking the film in a bath of 68 degree water will prevent the sheets from sticking together when you put them into the development bath. When the film is presoaked, thirty seconds should be added to the development time. Extreme care must be taken to avoid scratching the emulsion side of one piece of film with the corner of another. Also be careful not to touch a dry sheet of film with your wet fingers. The safest method for developing sheet film in a tray is as follows:

1. Fan the dry sheets so that they can be grasped individually.

2. Quickly immerse the film one shot at a time in the presoak bath face up to avoid trapping air bubbles against the emulsion.

3. When you move your film from the presoak bath to the developer, place each piece of film face down and keep the film from floating around.

4. To agitate, pull the bottom sheet out and move it to the top.

5. Keep repeating this process for the duration of the development time. Make sure that the sheets remain face down. This will protect the emulsion side of the film from being scratched.

With the tank method, the sheets are first put into individual metal hangers and then are developed together in an upright tank. To agitate sheet film in a tank, use the following method:

1. At the beginning of your development, slowly lower the hangers together into the development tank.

2. Tap them sharply against the top of the tank to dislodge any air bubbles that may be on the surface of the film.

3. Lift the hangers out of the developer together and tilt them to the side until the excess developer has run back into the tank.

4. Re-immerse the film and repeat step 3, tilting the hangers in the opposite direction.

5. Repeat steps 3 and 4 for the first fifteen seconds of every minute, following the agitation plan outlined above.

Proper sheet-film agitation requires careful planning and precision. Before you attempt either tray or tank development, I would suggest that you ask an experienced film processor to demonstrate how it's done.

Whichever method you use, always use fresh developer and develop the same amount of film in your tank or tray when possible. The more film you process in a given amount of developer, the faster the developer will be exhausted.

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