A Beginner’s Guide to Developing Film

©opyright by James Ollinger. All rights reserved.

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This is my own short guide for people who want to develop their own B&W film. I’ve divided it up into separate steps and treat them in depth. This isn’t meant to be an encyclopedic reference, but I think it is more important to discuss things fully rather than to present one of those brief overviews that are quick to read but leave too many important questions unanswered. I will not discuss equipment in detail here—for that I suggest reading a related article, A Beginner’s Guide to Darkroom Equipment. I also encourage beginners to look at photography books that cover the subject; many have photographs and they will explain things differently, and a beginner may find one more helpful than another in covering a particular point.

This article describes the process of developing roll film, as just about any beginner will be starting with roll film. Sheet film follows a very similar procedure, but it uses different equipment and handling techniques.

In a nutshell, roll film is developed in the following way: First, in total darkness, the film is removed from the canister (in the case of 35mm) or the spool and paper backing (in the case of 120). It is then wound onto a spiral and placed into a light-tight tank. With the lights on, chemicals are poured in and out of the tank which will bring out the image on the film, make it permanent, and render it safe to further exposure to light. Then the film is removed from the tank and dried. The difference between processing color film and B&W is the kind of chemicals used.


  1. Practice
  2. Loading the Tank
  3. Preparing the Chemicals
  4. Developing the Film
  5. Drying and Storage
  6. Congratulations

Step 1. Practice

Equipment needed:

Practice is the most important part of starting any new darkroom procedure. Loading film into the tank is often difficult at first, and it is even worse in total darkness. I highly recommend that beginners practice loading the tank with already developed film; it will save a lot of frustration later on.

The first thing to do is familiarize yourself with the tank. There are all kinds of tanks and they vary in a variety of ways. Fundamentally they’re all the same in that they have three parts—a cup, a top, and a reel. Some have pieces that hold the reel in place, or a spindle that turns the reel, or a cap that goes on the top to the tank so it can be turned upside down without pouring the chemicals out. If you bought a new tank, it should come with instructions that explain how it works. If not, you’re going to have to figure it out yourself.

The next step is the hardest—putting the film onto the reel. You need a developed roll of film to practice loading onto the reel. The easiest thing to do, if you don’t want to waste film, is to shoot a roll of film (B&W or color, it doesn’t matter as long as it’s the same format you’ll be using), then take it to a photo lab and have it developed. But tell them you want the film returned to you as a long roll. They will do this for you. They normally cut the film into short strips so that it fits into the same envelope the prints come in, but if you ask they’ll leave it uncut, roll it up, and put it into a film canister. Otherwise, if you don’t mind wasting a roll of film, just yank some film out of a cartridge or off the spool and use that.

Reels generally use one of two methods to load the film—either you clip or hook the end of the roll to the center of the reel and start winding outward, or you start the film at the outside of the reel and push it on. Both have their ups and downs. Winding outward is commonly found on stainless steel reels. The problem is that a) you have to clip the film on straight or it’s going to buckle and kink fiercely, and b) it’s very easy to miswind it and kink or buckle the film, which may make the film surfaces touch and the film won’t develop properly. Plastic reels usually use the push-method or some variation of it. Pushing can work, but it may require a lot of finger contact on the surface of the film and that can cause scratches or fingerprints. Better reels tend to have ways of helping the film on. Mine uses little ball bearings to grab and pull the film while you twist the reel. Using a ratchet action, the reel walks the film in.

So you want to determine the method you need to use to load the film onto the reel. Then wash your hands well (to get rid of any grease, grit, or dead skin you may have on your hands) and pull on at least one cotton glove. That will help protect your negatives from scratches and fingerprints. You only really need one glove—whichever one will handle the film—but if you’re fumbling around, one on each hand would be better.

You don’t really need the gloves for practice, but at some point (before you go into the dark) you should try it with the gloves at least once to get used to the feel.

Now start loading the reel—in daylight, and do it until you’re good enough to load the reel without paying attention to it (this is a great thing to do while watching television).

Once you get to where you can do it in the light, you need to practice a couple times in the dark. The room doesn’t have to be pitch black, but it should be dark enough that you can’t see what you’re doing. Set the items out and note where everything is so that you don’t have to hunt for things. Then practice loading the reel and putting it into the tank.

When you’re ready for the real thing, you’ll need to load the film in total darkness. There are two ways to do it.

The first way is to use a changing bag, which is available through camera stores. A changing bag is a heavy, light-tight bag with a zipper to open it and two sleeves. You unzip it, place everything into the bag, and then zip it back up. Then you place one hand in each sleeve. This gives your hands access into the bag and blocks out any light from outside. The nice thing about changing bags is that they can be used anywhere—you don’t need a dark room. They’re also useful if film jams in a camera in the middle of a roll, and you want to extract it without exposing the film. The problem with them is that they’re small and cramped, and it can become crowded with all the parts laying around.

The second way is to use a light-tight room. Any place that can totally block out light and allow you enough room to work will do. I recommend checking thoroughly first. Sit in the room you want to use for 10 or 15 minutes (take a radio or something to help pass the time) to give your eyes time to adjust. It’s amazing how many rooms that look pitch black at first become relatively bright as your eyes adjust.

With that done, it’s time to go on to the next step.

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Step 2. Loading the Tank

Equipment needed:

35mm and 120 rolls use different methods to keep the film secure. A 120 roll has a light-tight paper backing that goes along the length of the film and both are rolled onto a metal spool. 35mm rolls don’t have that backing—the spool is located in a light-tight metal canister and the film is rolled up inside that.

There are two methods of removing film from the 35mm canister. The method I prefer is to pull the leader out of the canister using a leader retriever (or simply leave the leader hanging out when you rewind the film), and then cut off the tongue—that little extension that’s used to make loading the film into the camera easier. You can do that in daylight. When you move into darkness (either into a dark room or a changing bag), you then just pull the film back out through the cartridge and cut it off the spool. This creates the least mess and allows you to use the canister again if you use bulk film.

The other method is to take the canister apart in total darkness. Some canisters are easily popped open, but many (particularly Kodak) have to be pried apart. I use the can opener on a swiss-army knife. If you have a dark room, though, you may want to get the kind of tool that mounts onto the wall. You place the end of the can on the tool and then tear it away. Pulling apart the canister may be easier than removing the leader, but it creates a lot more mess since you’ll have a bunch of canister parts around.

For 120 film, the method is (in darkness) to unwind the film from the canister, separate the paper backing and discard it (be sure not to load the paper onto the reel and discard the film. It sounds ridiculous but it does happen), and load the film on the reel as usual.

I suggest you have a light-tight can with you—anything will do as long as it’s large enough to put the film in. If things go badly and you need to turn on the lights to find something or to reread instructions or whatever—you’ll be able to put the film into that can and keep it safe while you turn on the lights. You could use the tank, but if the tank is part of the problem (i.e. you dropped the lid or you can’t get it screwed down right or something broke) then it won’t help. Changing bags work well for this (just tuck the sleeves so that light can’t leak in).

Once you have the reel loaded and into the tank, you can turn on the lights. It’s time for the next step.

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Step 3. Preparing the Chemicals

Equipment you will need:

Color film developing is much simpler than B&W in the following regard. There are two main kinds of processes for color—negatives use a process called C-41, and slides use another called E-6. Each process is a collection of chemicals and steps necessary to properly develop the film. The chemicals are usually purchased sold together as a kit with instructions that explain exactly how everything should be done.

General purpose B&W films use a process that has considerable variation in the chemical steps. B&W development uses a developer,; a stop bath, and a fixer. There is a variety of formulae for each of those chemicals. And there are optional steps that can be performed as well. B&W development can be very confusing for a beginner.

I’ll go through each step sequentially for the three common steps.


When the film is exposed to light, there is a certain chemical change that goes on in the film’s emulsion. The developer reacts with the silver in the emulsion that was exposed to light. The exposed portions turn dark—varying with the amount of exposure to light received and the amount of development given.

The developer has the most influence in how the negative is going to form, and as such, it’s very important to choose a developer that will do what you want—or at least to understand how a given developer will behave. Developer packages all come with little data sheets that explain what the developer is like and how to use it. In addition, some companies (like Kodak) provide literature that compares the action of various developers. For those who are interested, here is a short description of what some of the terms mean.

Some developers are high contrast—certain exposure levels will develop very darkly and others will develop very lightly—making for appreciable contrast between the light values and the darks. Other developers are low contrast, which means that different exposure levels won’t develop so differently. Thus there won’t be as much contrast between the low values and the light values. Among Kodak products,HC-110, for instance, can be used for both medium and high contrast work. D-76 and T-Max tend to be medium contrast. Microdol-X is relatively low contrast, and Technidol is extremely low.

Developers are important in determining the size of the grain in the negative. Most popular developers now are fine grain or better. Seventy years ago, when 35mm was primarily movie film and popular cameras took large roll film and the pros used large roll or sheet film, grain size wasn’t so important because the negatives didn’t have to be enlarged as much. Kodak’s D-76 offers moderately fine grain. Microdol-X is finer. Edwal’s UFG stands for “ultra-fine grain.”

When examined closely, some images have sharp grain edges and some are fuzzy. The edge sharpness is called acutance. High acutance doesn’t really make the image itself any sharper, but it does lend apparent sharpness—i.e. it may make the image look a little sharper than it is, just a low acutance may make the image look a little less sharp. It is beyond the scope of this article to discuss how acutance is controlled by development, but it should be noted that some developers are naturally higher acutance (such as Acufine) and some are naturally lower (D-76 undiluted).

Many beginners do not understand the role that developers play in determining the speed of the film—because film speed is rated on the box. Tri-X is rated ISO 400, Plus-X is 125, T-Max comes in various speeds, etc. The rated film speed is a ballpark figure, and it varies depending on how it’s developed. Microdol-X, for instance, offers a slower emulsion speed than D-76. That means that if two rolls of the same type of film were developed in Microdol and D-76, the roll used with Microdol would have a lower film speed than the one with D-76.

Compensating Developers
If you read many developer data sheets, sooner or later you’ll come across the term “a compensating developer.” As with acutance, it’s beyond the scope of this article to explain how it works, but here is a synopsis. A compensating developer offers extra development in the shadow areas of the negative—i.e. those areas of the image that received relatively little light exposure. This is useful in photographs were the photographer wants shadow detail that may not normally come out. When you buy a roll of film, it will have a data sheet that suggests a developer (perhaps several) to use with it. I recommend that beginners get whatever primary developer the film manufacturer suggests. If it’s still confusing, start off with D-76. It’s a very well known, well behaved, standard developer that will work with almost anything. A very important note—make sure the developer you get says it is meant for film, not paper. Paper developers are too contrasty and grainy for film work.

Stop Baths

The stop bath is almost always acetic acid that’s been diluted in water. It may or may not have a couple of other additives in it which I will discuss in a moment. Its role is to halt the action of the developer, hence its name.

Unlike developers, there are only a few variations of standard stop bath. The simplest version is marketed as 28% acetic acid. The user buys a pint of it and then further dilutes it at home to working strength. One pint of 28% acetic acid makes a lot of stop bath, and B&W developers aren’t very taxing on it—so it’s one of the very cheapest and most economical of all the chemicals used.

Sometimes acetic acid is sold in 99% glacial form. The term glacial comes from the fact that it usually looks frozen or semi-frozen. Glacial acetic acid is even more economical than 28%, but it has a lot of problems. First, the freezing point is relatively high (around 62°F), so in cold weather you have to warm it up to pour it. Its flash point is around 103°F. It’s extremely caustic, can burn the skin and the eyes, and it’s inflammable so you have to keep it away from heat and open flame. I always recommend that people avoid glacial acetic acid because it’s too dangerous for its meager economic advantage.

Some stop baths have additives. The most common is an indicator—a chemical that changes color depending on the pH (acidity) of the liquid. As the pH of stop bath rises it becomes less effective, so a good indicator can tell you when to throw away the stop bath. I recommend getting a stop bath with an indicator—if you don’t, you’ll have to calculate how much film has gone through it or throw it away more often than necessary. If the stop bath gets exhausted, the developer will contaminate and shorten the life of the fixer.

Another additive in some stop baths is a hardener, which effects the emulsion. Hardeners make the emulsion less likely to swell—for when the swelling goes down the emulsion will wrinkle, an effect called reticulation. I recommend against it unless reticulation is an actual problem. Only use hardening stop baths if the film manufacturer recommends it.


Like stop baths, there are only a few fixer choices, but there is more variation than in stop baths. Fixers use a chemical called thiosulfate (pronounced thigh-oh-sole-fate) to remove the unexposed silver in the negative and render it insensitive to light. If you didn’t fix the image, the images emulsion would continue to be light sensitive and, over time, the whole thing would turn black.

Note: older books or reference material used to call this hyposulfate and the fix step itself was called hypo. There are still chemical baths on the market that refer to this, such as Kodak’s Hypo Clearing Agent.

There are three kinds of thiosulfates—potassium, sodium, and ammonium. Potassium thiosulfate is the weakest and works so slowly it’s not used for photographic purposes. Sodium thiosulfate is faster and is the most common. Ammonium thiosulfate is the fastest of the three, and is used in “rapid” fixers. Rapid fixers are most often used in machines where timing is precise and mistakes aren’t made and speed is important. Most people who process by hand or in small machines use regular fixer (based on sodium thiosulfate) —because it works slower, it is mmore forgiving of error.

Some fixers are hardening fixers and some are not. The most common ones have hardeners added. Some people do not like hardeners because the emulsion doesn’t wash as easily when it’s hardened. Also some later treatments, such as toners, may not work as well if the emulsion is hardened (this is more often a concern in paper printing). On the other hand, hardened emulsions are less susceptible to reticulation.

For beginners, just buy whatever fixer the manufacturer recommends. Chances are it will be a simple, hardening, sodium thiosulfate fixer.


I discuss the merits of various kinds of bottles, thermometers, and the like, in A Beginner’s Guide to Darkroom Equipment, so I will not discuss them in detail here.

The first thing to do is to set up a work area. The best place to work is a sink and countertop where you can clean up the mess. I advise against working in the kitchen since some of the chemicals may splash and the powder will become airborne dust. A bathroom is a much better place.

It would be a good idea to wear protective clothing—gloves to protect your hands, goggles for your eyes, a breathing mask (the kind used by painters and hay-fever sufferers), and an apron or smock to protect your clothes. If you’re like me and you hate all that stuff, at the very least wear goggles to protect your eyes.

A note about water: photographic chemicals typically come concentrated as liquid or powder and have to be diluted in water. Many people are concerned about the quality of water to use. For beginners, I suggest that if you’re willing to drink your tap water, then the tap water is good enough to use for mixing chemicals. If the tap water is undrinkable or suspicious, then use bottled drinking water. Distilled water is the best, but I don’t think it would be worth the added expense.

Let’s start with the developer. The package will explain how to prepare it. A typical procedure is to start with a quantity of water heated to 125 degrees F, pour in the powder, mix it until it’s dissolved, then add luke-warm water until you get the full amount. I find it’s best to have a large pitcher to mix the chemicals before pouring them into the bottles.

Fixer will be prepared the same way, but the water temperature will be lukewarm.

Stop baths usually don’t have temperature concerns. But when mixing stop bath, always remember to pour the acid into the water, not vice versa. This is particularly important with glacial acetic acid.

A few tips:

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Step 4. Developing the Film

Equipment needed:

First, use the thermometer to take the temperature of the developer. The developer or the film will have come with a table that tells how long to develop the film at a given temperature (chemicals are more active as they get hotter). Most B&W developers work within a fairly large window between 65 and 80 degrees F. Below 65 degrees the chemicals will cease to work at all. Above 80 the developing times become so short that there’s little room for error. Developing times under 5 minutes (at any temperature) are to be avoided for that reason.

Some developers will have agitation instructions. If you just poured the chemicals into the tank and let it sit—those portions of the developer that contact the film surface will quickly become exhausted and quit working. Agitation stirs up the chemicals and keeps the chemical reaction going.

The typical agitation method is to agitate for 5 seconds every 30 seconds, or 10 seconds every minute. Agitation is performed by turning the tank upside down and back again if it’s an inversion style, or by twirling the spindle if it’s the rotation style. Use the times the manufacturer recommends. You can alter it later on when you get used to it. Constant agitation is usually avoided because the development is uneven—often streaky, or overdeveloped in the center underdeveloped on the edges.

When the developer is done, pour it out and pour in the stop bath. Stop bath is usually agitated constantly for 30 seconds. Pour it out. Then pour in the fixer for the manufacturer’s recommended time and agitate as the manufacturer recommends.

After about half the time it takes to fix the film, you can open up the tank and look at the results. I suggest waiting (fixing doesn’t take very long) until you’ve washed the film thoroughly. Pour out the fixer and start the wash. Tap water, unless it’s terrible, should suffice. Fill the tank with water and dump it—do this for a couple of minutes. This will perform the bulk of the washing and get rid of most of the fixer. Now you can pull a little bit of the film off of the reel and inspect your work. If the film looks okay, put it back on the reel and finish the washing cycle as the manufacturer recommends. If it looks bad and you know you won’t keep it, you might as well quit now and save some water.

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Step 5. Drying and Storage

Equipment needed:

When the film is done washing, use a clean squeegee or a soft, lintless cloth to wipe the water off of the film. Some manufacturers suggest using a wetting agent, such as Kodak’s Photo-Flo, to reduce the chance of getting water spots. I like Photo-Flo, but it is not necessary to the process. When you’ve wiped it down, hang the film vertically on a line using clothespins or film hanger clips. Use one to attach it to the line and the other to hold it straight.

When the negatives are dry you’re ready to inspect them and store them. Wash your hands and put on the lintless cotton gloves, and use scissors or a sharp knife to cut the film as you see fit. There are all kinds of things you can buy to store negatives. My favorite is the paper sleeve that comes in a long roll. By using a long roll instead of pre-cut sleeves, I can group my negatives however way I see fit—in 2’s and 3’s, singly, whatever. Precut negative sleeves are usually 5 or 6 shots wide—but I find that I waste a lot of space because I don’t cut my negatives into groups of 5 or 6.

Once you have them in the sleeves (whatever kind you use), put them away where you can get to them later on. I like to put mine in business sized envelopes and I keep them in a box.

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Step 6. Congratulations

That’s it. You’re done. Hopefully the film came out right. If not—try and figure out what went wrong and try again. Film developing is simple but it is an acquired skill nonetheless— and even people who are expert at it make mistakes.

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©opyright by James Ollinger. All rights reserved.