Developing your own black and white film at home isn't a particularly difficult skill to learn. I find it very rewarding and satisfying and I would absolutely recommend giving it a try.
There are many different methods to develop film and, chances are, whoever you talk to will have their own preferences and ways of going about the process. The method I am going to suggest is called "stand developing". Stand developing has several advantages over other processes. For starters, it's relatively fool-proof, the development chemical is cheap and lasts for years, and you can develop different films (even different speed films) at the same time. Is it the best method for quality results? Probably not but I think it's a great way to get started.
You are going to need to buy some stuff so there is an up front investment. It will cost somewhere around $200.00 or so to set yourself up. After the initial outlay you'll just need to buy replacement chemicals from time to time. Developing at home will pay for itself in no time.
Following is a shopping list of items you will need in order to to put together a good basic system, including the gear and the chemicals. Other people would no doubt recommend different items - there is a lot of debate about the merits of plastic tanks and reels vs stainless steel for example (personally I find the stainless reels a pain to use). A kit like this will do the job nicely and serve you well for a long time. Try other things later if you feel the need:
Step One - Load the film on to the reels, place in the developing tanks.
You are going to need a dark place to load the film. Completely dark. Any light can wreck your film. Some people do this at night in a wardrobe, in a toilet (not recommended), other people do it on their bed under a doona. I have a darkroom so it's easy for me but you will need to find a place that you can make light proof. Some people will buy a changing bag or tent, I find those things a nightmare to use for loading tanks but if it's your only option...
There is no easy way to do this but you need to learn to load the reels in complete darkness. Practice is key. Get an old film and one of your reels and keep loading it until you can do it comfortably with your eyes closed. It can be very frustrating at first but be patient and try not to rush. You will get the hang of it. It's important to note that the reels must be completely dry before you try and load them, they will not work if damp.
Once your reels are loaded, slide them on to the centre column then place them in the tank. Put the funnel lock into the tank and click into place. The tank is light-tight once the funnel is on securely.
Step Two - Pre-wash.
Fill the tank with water, put the lid on to the tank and invert it for a minute or so. Empty the tank and repeat until the water runs out clear.
Step Three - Developer
Pour one litre of water into one of your measuring jugs. The temperature of the water isn't crucial in stand development but it should be around 20°C. Measure out some Rodinal chemical and add it to the water. Officially the dilution ratio is supposed to be 1:100 but I have found, through trial and error, that 6ml of chemical in 1l of water works well for two rolls of 120 film. Be prepared to experiment over time to find a concentration that you like - keep notes whenever you vary the basic method.
Pour the developer solution into the tank. "Burp" the tank, prise the lid open a tiny bit as you gently press down on the centre of the lid - you should hear a little air escape. I always do this twice, it helps prevent leaks from around the lid. Gently invert the tank three times over five seconds. Tap the bottom of the tank sharply on your bench a couple of times to remove any potential air bubbles from the film, and place the tank down to rest.
Set the timer on your phone for thirty minutes. When the thirty minutes have elapsed invert the tank another three times, tap, and place back on the bench for another thirty minutes (sixty minutes minimum in total).
After the second thirty minute rest pour out the solution. Rodinal at this dilution will be exhausted and safe to pour down the sink.
Step Three - Stop bath (optional).
Stop bath ends the development process.
Mix the stop bath with 20°C water as per the directions on the bottle. It won't be much, depending on the brand, maybe 16ml of stop + 984ml of water. Pour the stop bath into the tank, burp the tank, and invert at least ten times. Pour the stop bath into one of your containers for re-use next time. If you buy an indicator stop bath it will change colour when it's worn out.
The stop bath stage is not entirely necessary with stand development as the developer will be exhausted. You could just give the film a rinse in water for a minute or two instead. I always use a chemical bath though, it won't do any harm and isn't much effort.
Step Four - Fixer
Fixer preserves the film and protects it against further exposure to light.
Mix the fixer as per the manufacturers instructions. Usually it will be 200ml of fixer plus 800ml of water. Pour the fixer solution into the tank, burp the tank, and invert continuously for one minute. The total fixing time may vary between brands, usually four or five minutes, generally you need to invert the tank for ten seconds at the start of each additional minute.
Pour the fixer into one of your containers for re-use next time. The fixer will change colour when it's worn out.
Expired fixer should never be poured down a sink or drain. There are several non-harmful ways to dispose of fixer, I suggest getting a large (5l+) plastic bottle and saving it until the bottle is full. Then take it to a chemical disposal facility if there is one in your local area. If that is inconvenient for you try searching for "photographic fixer disposal", I'm sure you will find a method that will work for you.
Step Five - Wash the film
After fixing, the film is no longer sensitive to light. It would be safe to remove the tank funnel but first all chemical residue needs to be washed from the film. The easiest way to do this is just run water continuously from the tap into the tank for ten minutes. Empty the tank and let it refill every few minutes.
Another way to wash the film and use less water is to fill the tank, replace the lid, and invert five times. Empty the tank and repeat with ten inversions then empty the tank and repeat with twenty inversions. I usually give the tank a couple of rinse and empties after that to be on the safe side.
You may now remove the tank funnel.
Fill the tank one more time and add a couple of drops of wetting agent to the water. Gently swish the water around for a few seconds.
Step Six - Dry the film
Remove the film reels from the tank. Carefully remove the film from the reel. I find the easiest way to do this is pop apart the reel and let the film drop into my hand.
Now, assuming you haven't made some catastrophic error, you should see your images on the film. Congratulations! If the negative is all blank, skip the rest of this step and spend the next ten minutes walking around swearing and kicking stuff over.
At this point some people will squeegee the film or run it between two fingers to remove any excess water. I pull the film through two lightly damp foam pads.
Attach a clip to one end of the film and hang it somewhere dust-free to dry. The shower is as good a place as any. Attach another clip to the bottom of the film to act as a weight and keep the film from curling.
Step Seven - Clean up
Wash and dry all of your equipment. It's boring but it needs to be done. Store your chemicals in a dark, cool, dry place.
Step Eight - Protect your negatives
Once your negatives are dry handle them while wearing cotton gloves to avoid finger prints.
The negative strips can be cut and placed into plastic film sleeves for storage. I keep sheets of these sleeves in lever-arch binders.
If you have fixed your film correctly and you store the negatives safely, they should be good for the next couple of hundred years or so.
Click here for a video on YouTube about stand development.