March - cumulus You are here: Home Techniques Processing your own films


Introduction

Most amateur and professional photographers who still use conventional film don't process their own film. I think this is because most don't know what is involved in processing film and think it is something complicated and expensive. It is not! Processing your own film is actually quite easy when you are past the quick learning curve, and it has several advantages over lab processing:

  • you can process the film when you want, also in the middle of the night, and you have the results immediately
  • it is cheaper in the long run
  • it is faster than bringing it to a lab, if you shoot only a few rolls per week
  • the film will have no scratches, fingerprints and drying spots if you handle it correctly (i.e. better than most labs)
  • complete control over pull- and push-processing, contrast and color balance
  • you are solely responsible for how the film comes out: you don't depend on other people who can mess up your film! If you mess up your film, at least you did it yourself.

Standard C-41 or E-6 film processing is quite simple. Are you eager to process your own film, possibly because a lab once completely messed up your film? Below I explain what you need and how to do the processing with minimal risk of error and maximal satisfaction. This is only my own experience though - but I have processed most part of my collection of films myself (576 rolls at the time of this writing), and never ruined any of them. Most of the few films that I ever brought to a lab came back either scratched, with fingerprints, or film strips cut badly (through frames).

This document assumes that you are processing standard 35-mm format film. 120 and 220 medium format film is also fairly easy to process, but must be handled more carefully.

What you need

These things you will need in order to do film processing yourself.

You will need the following to do your own processing, using the hand-inversion technique. This technique is fully manual and the cheapest to start with.

  • hand-inversion processing tank with film spirals (the spirals are what the film is loaded on to)
  • dark room (not necessarily a darkroom! Just a dark closet will do)
  • processing chemicals
  • one 1 liter (about 1 qt) graduate
  • one 100 ml (milliliter) graduate
  • four 600 ml storage bottles
  • thermometer that will read around 38C (100F) preferably with a precision of 0.1oC
  • flat kitchen sink with stop, and hot/cold water

The graduates, tank, chemicals, storage bottles and thermometer are readily available at professional photo stores and mailorder companies. The tank will be around $30 to $50 including the spirals; chemicals are around $15 per 500 milliliter (makes enough for 6 films) or $80 for a pack that makes enough for 60 films. The thermometer and the graduates cost about $40 total.

The dark room can be a closet (like I use; I don't have space nor money for a darkroom). Just make sure that when you are in the closet, there are absolutely no light leaks; you should, after you let your eyes adapt to the dark for 5 minutes, not be able to spot any light coming in under the door or elsewhere. Film needs to be loaded into the tank in the absolute dark to prevent the film from fogging.

The kitchen sink will have a standing water bath of 38C, assuming you are processing color print film (C-41) or slide film (E-6). (Most Kodak and all Fuji color films use these processes.) This water will continuously cool down at the rate of about 1 C per 5 minutes; you need to have a tap with hot water running at a trickle, or have a kettle with hot water on a stove, to keep the temperature constant. Short-period variations of +/- 0.5oC are acceptable. The tank with the film and the four 600-ml storage bottles containing the chemicals will be in this water, at the same temperature.

Once you have all these things, processing just costs around $1.35 per film if you buy larger packs of chemicals. I don't know a lab that will process slide and print film so cheaply with the high-quality results you get! This is why I say that it is cheaper in the long run. You still need to spend $100 or so for the equipment, but once you have this, it won't be long before you save that money by processing your own films.

This film tank is ideal for small film quantities and manual processing, since the tank has to be filled to the brim and since the tank is relatively small, you don't need too much chemicals.

Loading film into the tank

Usually when you rewind a film in a camera, the film gets spooled all the way into its canister. Bring a pair of strong pliers or a bottlecap opener with you to the dark room, as well as a pair of scissors. Also bring the tank with the spirals and set everything close to you before switching off the light, so you know where to feel in the dark to find something.

In the dark, take the film canister and open one of the ends with the pliers or opener. This works best on the end of the film canister that does not have the protruding axle. When you have the cap off, push out the axle with the film, taking care not to scratch its surface along the sharp edge of the metal.

Next, you cut the smaller end of the film off (about 3 cm or 1 inch) with the scissors, and stick the end of the film in the spiral. The spiral should have two notches on its sides that allow you to put your finger on the edge of the film, keeping it in place. Then, while carefully unrolling the film, wind it on the spiral as you go. Loading a film onto a spiral is easy, but you have to practice with a piece of wasted film in daylight first, and then in the dark also. The technique (at least for the plastic spirals I use) is to put your right index finger on the right side of the spiral, keeping the film in place, while you rotate the other side of the spiral a bit (the spiral consists of two parts that can rotate a short distance). Then repeat, keeping your left index finger on the left half of the spiral while you rotate the right part. It is easy to see once you try it, and it is fast.

Try to avoid having the surface of the film come in contact with anything like your fingers, body, clothes, the floor, etc. Only handle the film by its edges. Also, do not accidentally bend the film.

The end of the film will be fastened to the axle by tape, or stuck in a slot. Cut the end off, but cut it as short as possible, since the last frame of the film is often perilously close to the end. Then continue loading the film on the spiral until everything is on.

When done loading the film on spirals, put them on the center hub in the tank, and close the lid. Make sure all tank components are in place! If you forget one part, there will be a light leak and the film will be spoiled.

You will need to load the film onto the spiral (white in the picture) in the dark. Practice this first with a test film.

Mixing chemicals

Mixing chemicals is a somewhat precise job but it is fast and easy. I highly recommend using distilled water for mixing, at least for the final (stabilizing) bath; if you use tap or drinking water, there will almost certainly be drying stains on the film later.

The chemicals come with a booklet that contains information on how to mix the chemicals. The different baths for normal C-41 (print) processing are the color developer, bleach/fix, and a stabilizer. E-6 (slide) processing differs from this in that there is a first developer, that comes before the color developer. Most or all baths come in two parts that you have to mix with water. Depending on your tank, you need a certain amount of developer to fill the tank enough for the entire spiral(s) to be submerged. If you use the Jobo Unitank 1520, you can make exactly 500 ml of developer which will process 6 rolls of film, and process two rolls of 35mm, 36-frame film per time in the tank.

When you mix chemicals, always have at most one bottle open at any one time to avoid confusing the caps or contaminating the concentrates. This must be avoided at all cost! Also, first mix the earlier baths and then the later baths in that order, so if contamination of your working solution occurs, at least it is forward, which is less bad. Contamination of concentrates, and contamination of earlier baths by later baths would be bad.

You may want to use a finer-scaled graduate than the 100 ml one I recommended; the 100 ml graduate is fine if you make 500 ml at one time, since then you will need up to 100 ml of concentrates.

First developer usually comes in one part of concentrate, as does the stabilizer; color developer and bleach fix come in two parts.

All concentrates (and working solutions that are not used immediately) should be protected against oxidation. The easiest I found to work is to use butane gas for this, since this is a heavy gas and displaces the oxygen. Other people (and me too, once) use marbles to fill up space in bottles, but this is highly impractical.

Some people advise strongly against the use of gas to lengthen the storage life of concentrates. They say it is dangerous! They are very right in that. But then what about using a gas stove to cook food? If you use common sense, there is no more danger in using shield gas for your chemicals than there is to drive a car to the supermarket, or cross the street for that matter. Even so, decide for yourself if you want to use flammable butane gas for this purpose or rather choose to buy small amounts of chemicals to use at one time, every time. I will not be responsible for accidents!

Concentrates unprotected against oxidation will only keep for a couple weeks, otherwise they keep over a year if the bottles are closed tightly.

A simple warm water bath with a thermometer is all that is needed to keep the chemicals and the film tank at the correct temperature while processing.

Preparing and maintaining a warm water bath

The temperature of the water bath is essential for the processing. Have the level of the water bath approximately at the same level as the developer in the tank will have later.

When you first mix the chemicals they may be at room temperature, or 20oC. They need to be in their storage bottles within the warm water bath for about 30 minutes at least to warm up to the same temperature as the water. The water however will be constantly cooling (unless you use a thermostat ofcourse), especially when you put bottles with cold liquid in it, so make the bath about 42oC and let it cool to 38oC (or whichever temperature your developer needs, but 38oC is standard). The thermometer should be in the warm water bath constantly, so you can monitor the temperature precisely. (Tape it to the side of the sink, close to where the tank is.) Also, before processing, check the temperature of the solutions to check if they are the correct temperature.

38oC is about equal to 100oF, in case you are used to the Fahrenheit scale instead of centrigrades.

The water bath will get contaminated with solutions during processing, because some will always leak into the bath while you hand-agitate the tank by inverting it every 15 seconds. Therefore, after every batch of film you process, start with a new bath, to avoid contaminating the first developer, and any bath that comes before another bath in general.

The warm water can be kept at fairly constant temperature by letting hot tap water run into it at a trickle. Practice this technique first so you get a feeling for how much hot/cold water you need to increase/decrease the temperature of the bath by a certain amount. Stir through the water with your hands when you let water at a different temperature in, to get an accurate reading of the thermometer.

Preparing to process

Processing starts by putting the tank with the film (but without chemicals, still) into the water and hold it down with a weight, like a drinking glass or something. This should be done to get the tank at the same temperature as the water; if the cold tank would be filled with developer, the developer would instantly cool down several degrees and this would not be good.

While the tank warms up in the water, check that you have all solutions ready and at the correct temperature. Also arrange all bottles in the water (label them!) so that there is no chance that you will put in the chemicals in the wrong order; the film would then be ruined. Next, make a list of all processing times, that starts about 10 minutes in the future to give yourself time to get fully prepared. Do all timing and thinking before you start the procedure, since you can't really stop midway, and having a routine reduces the chances of catastrophe. An example list of times would be like:

10:23:30 1st developer in
10:30:00 rinse 3 minutes
10:33:00 color developer in
10:39:00 rinse 3 minutes
10:42:00 bleach fix in
10:48:00 rinse 3 minutes
10:51:00 stabilizer in
10:52:00 stabilizer out

When you are done writing up the times, check that the difference is equal to all individual times of every process. Re-check the list several times if you are not completely sure.

The list above is representative of E-6 processing like I do; 6m30s for first developer, 6 mins each for color developer and bleach fix, and 1 minute for the stabilizer. Between each bath there is a rinsing procedure, in which you let water of approximately 38 C in the tank, agitate continuously and let it flow out every 30 seconds or so. There is no rinsing with water after the stabilizer. If your chemicals don't come with stabilizer, rinsing with water after the bleach fix is the final procedure.

If you have a darkroom timer, it gets easier, but make sure you keep track of which bath is going in. Having a list like this that is absolute in the time of day won't confuse you. Also make sure that all bottles are clearly labelled.

Processing

When the first time on the list comes, lift the tank out of the water, remove the cap and quickly pour in the first developer. Then put the cap on tightly, and forcefully (not too forcefully) tap the tank on the sink a few times to remove air bubbles (these could otherwise ruin your film, since they cause discoloration!). Then invert the tank for a few seconds, turn it back and tap again, etc. Repeat this procedure for 30 seconds, then put the tank in the water bath. Every 15 seconds, invert the tank again for a few seconds, then tap it to the sink and put it back in the water. You need to be absolutely concentrated doing this. Don't let anything like a phone call or something else divide your attention! If you walk away longer than just 30 seconds or so from the tank without agitation, the film will almost certainly get streaked due to uneven processing.

While you are counting every 15 seconds, keep an eye on the temperature of the water and adjust if necessary.

One minute before the time comes to remove the bath, open the tap and adjust its temperature using the cold and hot water until you have flowing water of 38oC. Have the 1 liter graduate ready (make sure it is absolutely clean!). During this, keep inverting the tank every 15 seconds, don't forget this. When it is time, remove the tank cap and pour the developer in the graduate. Don't use longer than 15 or 20 seconds doing this, or there may be streaks on the film later. Then start rinsing by filling the tank with tap water, agitating it, emptying it, refilling, etc.

You will notice that during the few minutes of rinsing, the water bath will cool down. Try to have it at the correct temperature when you are ready for the next solution. It requires a bit of multitasking, but when you get a little experienced and the workflow going, it is fairly easy.

The storage bottles of the solutions that you used should remain out of the water, as to not confuse you later. Pour the solution back into its bottle from the graduate and rinse the graduate thoroughly every time. This all applies if you are reusing the solutions for later processing batches, something you can and should do.

For the succeeding solutions, proceed in the same way. When you are done with the bleach fix, however, you can actually open the tank up to rinse it more thoroughly. I recommend that the film is washed a long time, 5 to 10 minutes being optimal, although 3 minutes of rinsing is enough if it is done thoroughly. After that, pour in the stabilizer and let it stand for a minute.

Drying the film

One of the most rewarding (or disappointing, sometimes!) moments of the whole photography hobby is to pull the film off the spirals and see for the first time all the exposures, and then realizing that you did everything yourself.

It is tempting to inspect the film at this point, but try to resist: the film will be completely wet, not only on its surface but also within, and the colors will be more blueish than when it has completely dried. It is very easy to damage the film when it is wet.

Handle the film very carefully, not letting it touch anything while you walk with the entire strip to the place to have it dried. For drying, the easiest is a string or cord where you'd dry clothes on, and hang the film with a clothespin on the line. Also attach a clothespin at the lower end as a weight to keep it straight. Then walk away and do not disturb the drying room, or there may be dust in the room attaching to the wet film. Never "pre-dry" a film using a rubber stripper or alike. Doing so will almost certainly scratch the whole film. If you prepared the stabilizer bath with distilled water, or - in case there was no stabilizer - if you rinsed the film lastly in distilled water, the film will dry absolutely clean without stains.

It takes between 1 to 4 hours for a film to dry completely, depending on the atmospheric humidity. After drying the film, carefully cut it in 5-frame or 6-frame strips and store these immediately in a film storage sheet. Do not under any circumstance keep the individual strips out of protection to prevent them from being scratched. It is amazing how easily a film will scratch - sometimes you won't even see the scratch with the naked eye, but only when you make a large enlargement.

Some general advice

Some of the items below may sound a bit silly, but all of these have helped me avoid catastrophe at some point in time, therefore I am sure they will be helpful for others!

  • Try to depend as little as possible on mains electricity: having a candle or flashlight nearby, as well as a battery-powered clock will avoid major problems if there would be a power blackout.

  • Wash and completely dry your hands before you handle film.

  • Do not eat or drink while you are processing film. The processing chemicals are toxic. Also, avoid inhaling vapors, especially the stabilizer bath.

  • Make sure all graduates and such remain completely clean. In particular, clean the tank and spirals after every processing run. Avoid having the chemicals contaminated with one another. Never interchange storage bottles for chemicals that have contained another chemical before.

  • When you do multiple processing batches, the spirals and tank should be completely dried after each batch. Loading film on a wet spiral is very hard to impossible and will damage or stain it.

  • In general, make every action into a routine, and make every routine as fail-safe as possible. This will prevent you from doing actions that are not part of your routine and thus may be hazardous to your film. Follow routines, but don't get too automatic doing things!

  • The tank should be absolutely level in the sink. If it is a bit tilted, the film may not be completely submerged in the chemicals everywhere.

  • If you reuse chemicals for further batches, keep in mind that you loose some of it during every bath, especially of the first developer that enters into a dry tank every time. You may need to add a little water to the solutions from time to time if the amount of solution is close to the minimum suggested tank capacity. After doing this, let the solution get to the correct temperature again.

  • Make sure the water with which you rinse the film between baths is as close to 38oC as possible, to avoid getting small cracks in the film substrate.

  • If for any urgent reason the processing needs to be interrupted, immediately pour out the chemicals and rinse the film thoroughly with water. While you solve the problem, the film should remain under water at all cost to prevent drying stains: fill up the tank with water and try to continue processing as soon as possible. Only interrupt processing if absolutely necessary; it is generally not so good for the film.

  • The fastest method to learn how to process film is to have a tutor and have him or her supervise you during your first attempt. If there is no-one around, practice processing films yourself by using a test-film first, with exposures that are not critical. Do not be discouraged if at first things don't go too well.

  • Use common sense and make sure you are completely awake when you process film! Think with anything you do, e.g. before pouring in a chemical into the tank, think and check that it is the correct chemical.