This post is part 2 in my Developing Film series. You can read part 1 here where I go through putting your exposed film into a developing tank. In this post, I will give an overview of the process of developing film and will briefly go through the chemicals and equipment required. The next post in the series will then show the process in action. Also, this post is for black and white film processing. Color processing is slightly different and is something I do not have any experience with.
To process the film these are the steps I follow:-
2. Stop bath
5. Wetting agent
Development - In this step, the latent image on the negative is converted to a visible image. The chemical used in this step is called a Developer. There are many different kinds of developer from many different manufacturers. The amount of time the film is processed in this step depends on the type of developer and film being used. Instructions come with each developer listing recommended development times for various common films but a greater resource exists in the Massive Dev Chart online. Here you will find nearly all film/developer combinations.
During development, the developer needs to be agitated periodically so that fresh chemicals are adjacent to the film. This is usually done by inverting the tank a few times every 30 seconds or every 1 minute.
Stop Bath - To prevent continuing development, a Stop Bath is used. This is usually a very diluted solution of acetic acid or citric acid. Some people use water instead of chemicals in this step.
Fix - Up to this point, the film is still light sensitive so a Fixer is used to make the image permanent. After this step is complete, the developing tank can be opened and the film can now be exposed to light.
Wash - During this step, the film is washed to remove any traces of chemicals which can harm the archival properties of the film. Washing can be achieved by using running water for 5 to 10 minutes or by using the "Ilford Method" which uses less water. In this method, the tank is filled with water and inverted 5 times. Fresh water is then used and the process repeated for 10 inversions and 20 inversions.
Wetting Agent - This is an optional step. Here a very small amount of surfactant is added to water. This helps the film shed water faster and helps speed up drying. I also helps reduce the formation of water marks than can occur during drying.
Dry - The film is obviously still wet so needs to be dried before it can be printed or scanned. The film is removed from the developing reel and hung up to dry. Dust is your enemy now so the place being used must be relatively dust free. Once the drying is complete, the negatives can be cut into strips and stored in a plastic negative sleeve.
Chemicals I Currently Use
There are many different chemical manufacturers and each manufacturer may have different chemical product lines with different properties. What you use is a personal preference but this is a list of what I am using these days.
Developer - At the moment I am using Kodak HC-110. In the US, this developer comes in a highly concentrated form which must be diluted before use. It is best to dilute right before processing since it last longer when stored in its concentrate form. This is a "one shot" developer so is discarded after use.
Stop Bath - For the stop bath I am using Kodak Indicator Stop Bath. This stop bath can be reused many times. It will change color when it is exhausted but as far as I can tell it lasts for a very long time without needing to be replaced.
Fixer - Right now I am using Ilford Rapid Fixer. This can be reused multiple times. When fresh, this fixer can fix film in about 2 minutes but as it gets depleted it can take about 5 minutes to adequately fix the film. Every so often I test how good the fixer is by putting a snipped off film leader into some of the fixer. I time how long it takes for the film to become clear and will then use twice that time for my fix.
Wetting Agent - I use Kodak Photo Flo. The amounts of this stuff you use is so minute that I think the bottle I have will outlast me.
In addition to the chemicals, some equipment is needed.
Thermometer - Most developing times are listed for 20 deg C (68 deg F) so the temperature of the chemicals is important. With black and white there is some leeway but it is best to have the developer at the recommended temperature.
Graduated Cylinders - You will need a few of these. I use a 50 ml one for measuring out small amounts of chemicals (like the developer) and I have a few more ranging from 300 ml to 1200 ml for the other chemicals. I use my cylinders to hold the chemicals while I am processing but some people use dedicated beakers for this.
Stirring Rod - To mix the chemicals you will need something to stir with. I actually use my thermometer for this because mine is a dial type thermometer with a long metal rod that is inserted in the liquid. If you are using a glass thermometer it is probably not recommended to stir with it.
Stopwatch - You need some way to time each of the steps so a stopwatch or clock is required. I actually use the Massive Dev Chart iPhone app which contains the film/developer database and has a built in timer. You can read my review of that application here.
Film Clip - These are small metal clips that are used to hang up the film to dry. When I started developing many years ago I used clothes pins to hang up the film.
Storage Bottles - Some chemicals are "one shots" so will be mixed before use and discarded after. However, some can be reused many times so you will need some containers to store them. The containers should be opaque and be rated for chemical storage to avoid spoiling or leaking. It is best to use bottles specifically designed for photographic chemicals.
Negative Sleeves - These sleeves store the negatives with cut into strips of 6.
Where to Buy
It is getting more difficult to find chemicals at local photography stores but some still carry some limited supplies. My local store only carries a few brands and not the ones I use so I buy my chemicals at Freestyle Photographic Supplies.
Because many people have switched to digital, it is possible to buy the equipment needed on eBay or Craigslist for real cheap so it is worth doing a some searches online. But if there is nothing suitable Fresstyle also carries a huge selection of supplies.
In the next post, I will go through the development process that I follow in detail.