The tank is light tight. The film is rolled onto a reel which is a spiral that keeps a space between the layers of film, so the developing solutions can flow evenly onto the surface of the emulsion. The bottle opener is used to pop the top on the 35mm cassette. The scissors are necessary to cut the film leader before loading film onto the reel. An accurate darkroom thermometer is extremely important because the length of the development time is determined by the temperature of the chemicals, and for proper processing all the developing chemicals need to be at the same temperature. You will also need as many measuring beakers as there are steps in the particular developing process you are using, according to Andrew Gibson.
It is important to have an accurate way of timing each step in development. A timer that lets you program in several steps is best. The chemicals needed will depend on the type of film you want to process.
I suggest starting with black-and-white film because it is the most forgiving and many times can be done at room temperature. Black-and-white film development uses three chemicals: developer, stop bath and fix.
step 2: Read the instructions that come with the chemistry you have selected and follow the mixing procedure precisely! To avoid contamination, mix the chemicals in the order you will be using them in the process. Mark the graduates so you won’t confuse the solutions.
step 3: Once all three liquids are in their appropriate beakers, take a temperature reading in each liquid. All chemistry readings should be the same. For black-and-white processing the stop bath and fixer can vary [+ or -]5 [degrees] from the developer temperature. The standard recommended development temperature for black-and-white films is 68 [feet] [degrees] F. If you find that your developer is hotter or colder than recommended, you will need to adjust the recommended time for the developer step accordingly. A better approach is to bring the temperature of your chemicals to 68 [degrees] by putting the beakers into a water bath that keeps all the chemicals at the same processing temperature. It might take a little time for the temperature in the beakers to adjust.
step 4: While in total darkness, roll the film onto the spiral reel. (If you have never done this before practice on a dummy roll while still in the light.) Place the loader reel into the film tank and close the lid. While the tank top has an opening to let the chemicals get in and out, it also has a light-tight baffle to prevent unwanted exposure.
step 5: Check your temperature again. If it is still correct, pour the developer into the developing tank and start your timing. With one hand on top of the tank and the other on the bottom, turn the tank upside down and back. This is called inversion. The force you do this with is called agitation. Do this continuously for the first 30 seconds. Tap the tank lightly on a counter to dislodge any air bubbles that might be clinging to the film. Agitate for 5 seconds every 30 seconds, or 10 seconds every minute. This will depend on the type of developer you are using (check the package).
step 6: Start draining the developer 10 seconds before the end of the developing time. That way all of the developer is out of the tank when the developer time is up. Next pour in the stop bath. Agitate for 30 seconds and then drain completely.
step 7: Now it’s time for the fixing bath. Follow the directions on your fixer for the proper amount of time. Agitation is necessary in the fixer as well. Use 10-second inversions every minute unless otherwise indicated by your type of fixer.
step 8: Remove the tank top and wash the film in running water ([+ or -]5 [degrees] of the developing temperature). Washing time should be about 20 minutes unless a washing aid is used.
step 9: After the final wash, the film should be soaked for a minute in distilled water with a wetting agent to prevent water spots drying on the film.
step 10: Now your film is ready to hang up and dry. You can use clothespins at the top and a weighted film clip at the bottom to get the film to dry without curling. You’ll want to find a dust-free area (like the bathroom) to let the film dry.
step 11: Cut the dry negatives into five or six frame strips and put them in protective sleeves. I use cotton gloves when handling negatives to keep the film as clean; clean negatives make clean prints.
Proper film processing does require some attention to detail. But as you become more familiar with the process the steps will become routine. Establish a consistent way of working and your film will show consistent results.