How to develop film successfully

The first thing to remember when learning to develop film successfully is to stick to one film, one developer, and one method of development. It is the only good way to learn a sound technique and to fully explore and maximize the potential of the film and ultimately your print.
Keep in mind that the only purpose of developing film is to make the best prints you can make. It doesn't matter how the negatives look to your eyes as long as they produce the results in the prints that you originally wanted.
What films and developers to use? That is a question I get a lot. Any of the available ones will give you acceptable results, and you can't really go wrong. It also depends on what results you're after. Remember that there are no silver bullets when it comes to film or chemistry. They can help you get the results you're after, but the main factor is technique in exposing the film, developing it, and ultimately printing it. The work of the artist is by far more important than the materials used, so try to focus on repeatable results, and please remember to print your images often, only then can you truly know if your negatives are developed well or not.
Important factors:
1. Temperature. Some developers work fine in a temperature range between 65*F and 80*F, others don't. It's safest to keep the temperature you choose to develop at constant, at least in the beginning, and since so many recommended developing times are recommended at 68*F (or 20*C) I stick to that temperature religiously.
2. Time. Consistency requires exact timing, and the best way to achieve that consistency is to make sure the procedure for developing your film is the same every time. Don't change a thing.
3. Persistance. Don't give up if you don't get results immediately.
Basics:
When developing negative black and white film, the image is of course a negative of what your print will look like. That means the areas with the lowest density of developed silver will be the darkest in the print, and the areas with the highest density of developed silver will become the highlights. The dark tones in the print, or the 'thin' parts of the negative develop slowly, because they receive less light at the time of exposure. How much detail you get in this area of your negative depends on how you exposed it in the camera. Overexposed negatives will generally produce very generous detail in the print shadow areas, while underexposed (too little light) will invariably produce blocked up shadow areas without any detail at all. When you develop your film, the density of the developed silver in those areas is practically unaffected by developing the film longer.
The dense areas of your negative, or the highlights of your print, is a different story. This portion of your negative is determined solely by development. Several factors affects the results, mainly developer concentration, developing time, how you agitate your tank, as well as chemistry temperature. This is the reason why it's so important to be accurate in your methods of developing film.
My method of developing film:
The following method works great for me. You may wish to adopt it and do as I do, or you may find that some other method works better for you. We all have individual needs and desire different looks in the finished print.
1. Presoak the film in plain water. I do this for 3 minutes in water that is the same temperature as the developing chemistry. There are some developers that specifically shouldn't be used with a presoak, but 95% of them benefit from it. (The film emulsion is embedded in gelatin, and it swells. Presoaking makes sure the gelatin is properly swelled up by the time the developer is poured in and ensures more even development).
2. Developer. 20*C or 68*F, I mix one shot 'single use' batches of developer just minutes prior to developing the film. After pouring the presoak out, I immediately pour the developer into the tank. When it's all in the tank I start a timer that displays seconds and minutes, counting backwards from my predetermined developing time. I agitate for the entire first minute by inverting my tank with a lid tightly capped onto it. After about 50-55 seconds have passed, I very firmly rap the tank on the counter space six or seven times. This helps air bubbles that can get trapped on the film to dislodge and come to the top. The air bubbles will adversely affect your film development and turn up as marks, usually round and along the edge of the film strip.
3. Agitation. I completely invert the tank every minute a couple of times, and before setting the tank back down, I rap the tank on the counter top to, once again, dislodge those harmful air bubbles. The inversion ensures that the mixed developer acts evenly on the film surface.
4. Stop bath. 15 seconds prior to the film developing time being up, I start pouring the developer out. Then right as the development time ends, I pour pure water into the tank (at 20*C or 68*F, same as the developer). I do NOT use a stop bath since it is known to sometimes be the source of 'pinholes' in the film emulsion, showing up as dark spots on your prints. Developer is alkaline, stop bath is acid. The very large difference between developer and stop bath pH causes this phenomena to happen. You can use a stop bath if you like, but water stops development almost as well, and you run much less risk of pinholes. I change the water a couple of times for a total rinse of about 1-1.5 minutes.
5. Fixing. This is a critical stage of developing your film. It is extremely important to use fresh fixer, because it removes the unexposed silver in the emulsion that the developer didn't develop. If your fixer isn't fresh, or is spent, it will loose its ability to remove that unwanted silver. I always test my fixer before I use it by putting an undeveloped piece of film into the solution. The film strip should clear within the time the manufacturer recommends to use the fixer. I double the time it takes.
The fixer I use is alkaline. You can use acid fixer if you like. They are OK, but alkaline fixers wash out of the emulsion faster and easier. Do not use an alkaline fixer after using an acid stop bath.
I agitate constantly for the entire duration of the fixing. My fixer takes one minute to clear the unexposed silver when it's fresh, so I fix for two minutes. Then I pour the fixer back into its container and continue to use it until it's spent (when the clearing time exceeds the manufacturer's recommended fixing time, or preferably before that point, it should be discarded).
6. Washing. I use the Ilford-method of washing my film. After pouring the fixer out, I rinse with fresh water and a couple of inversions. Then I dump water. Pour in fresh water, invert tank five times. Dump water. Pour in fresh water, invert tank ten times. Dump water. Pour in fresh water, invert tank twenty times. Dump water. Rinse in fresh water for about five minutes, and finally do a rinse in distilled water to avoid drying marks on the film to the largest possible extent.
7. Wash aid. Some people like to use wash aids such as Kodak Hypo-clearing agent. With the alkaline fixer and the Ilford washing method there is no need. The purpose of washing film is to wash out unwanted chemicals. The hypo-clearing agent itself must be washed out for archival washing, so you're back to square one. With acid fixers, it may be necessary to use, however.
8. Rinse aid. Kodak Photo-flo (one among many similar products, Kodak is the best known), is a good tool to help the water to run off from the emulsion surface. Use distilled water and follow the instructions.
9. Drying. I hang my film from a nylon line with weights on the end. No air movement to minimize dust sticking to the film emulsion. Drying time varies with Relative Humidity level.
This method has been bullet proof for me. Which materials to use is related to personal taste and you will get as many suggestions as people you ask which film or developer is best.
Good luck, and remember to stick to selections that are the same every time, at least until you master those materials and explore them fully. Then you may venture off and try something else on an experiment level. Until then, keep it simple!
- Thomas
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