This is a rough outline of the material I usually cover in the ' HOW TO DEVELOP A ROLL OF FILM' class for the Hart House Camera Club.

Introduce self-- position in club-- role of club-- members helpful-- ask questions--

This is part I of two, the second part is how to make black and white prints--it is on at p.m. It makes sense to teach you how to make a negative before we teach you how to make a print!!!

REASONS FOR DOING YOUR OWN PROCESSING:

artistic satisfaction

speed- many places take a week: you can develop and print a roll in an evening

cost-- the club supplies the raw materials for processing solutions for free--control-- you only have ASA (ISO) 100 film, and need to take pictures in low light-- you can expose the film at 1000 and push-process. Also, if you' goof' on the exposure, and know that you have done so, you can correct in the processing-- The Secretary of the Squash Committee brought me a roll and a light meter-- we deduced that he underexposed by 5 f-stops (ASA 3200 rather than 100) --I developed the roll in concentrated developer for

5x the suggested time, and we got o.k. prints-- a bit grainy, but the Varsity published them, and no one noticed the grain--

You can buy the film in 100 foot rolls, load your own, and save 2/3 of the cost of film

Also, you can achieve some spectacular' special effects 'if you do your own processing. An example is reticulation, or a wrinkled effect. This can be achieved accidentally if your temperatures are way off ( care!)

CAVEAT ; Practice first on some pictures that are not irreplaceable-- don't be the only photographer at a wedding, and experiment on that film!!

This evening we will cover the process three times:

Theory--- just so you have a background - just get the flavour, don't let the chemistry confuse you—

Practical Aspects: what you need to buy, what you need to do and tips on doing it. You will need a developing tank, thermometer, and photo-flo solution. You may want to start by buying prepared chemistry from one of the major camera shops in town, to cut down on the list of things that can go wrong.

Demonstration-- actually develop a roll before your eyes (well, some parts have to be done in the dark) We will go to the darkroom if we fit, otherwise we will bring the chemicals up here to the club room-- but load the film into the tank downstairs--

Theory:

Photographic film is composed of a backing of cellulose acetate (a plastic-like film) with a layer of hardened gelatin on it. (Jell-O doesn't quite work) In this gelatin is suspended minute crystals of a silver compound, silver halide. The silver halide is affected by light, so is kept in the dark. When you expose the film in a camera, light from bright objects is focused on these microscopic grains of silver, causing a minute chemical change in them. Where no light strikes a grain, it is not affected. This forms the latent image.

To bring out the image, you place the film in a developer solution, for a certain time, at a certain temperature, with agitation, and the crystals touched by light are converted to pure silver. The crystals are so small they look black, not silvery. Those crystals not touched by light do not develop, unless the developer is left in contact too long.

To stop the developer action after this critical time, you use a stop bath, or several rinses of water. The stop bath is dilute acetic acid (very dilute vinegar)

At this point we have a picture (a negative) but the unexposed silver halide has to be removed with a fixing solution. Then the chemicals must be washed from the film, and it is dried, ready for printing.

End of theory-- quick and dirty-- any questions??

Film

Various films are made, for different purposes. The larger the grain size, the less light is needed to make a proper exposure, but the grains show up when making enlargements. (Recommend a film for beginners-- maybe plus-x- a good general purpose film)

Developing Tank

There are two types in common use - plastic or metal. They allow you to work with the lights on, once you have loaded the film into them, and closed the lid. It helps to see the bottles that you are pouring-Show different types, and how to load them--. The club provides tanks, for sign out at the Hall Porter, but you are better off with your own – you know it is clean.

Thermometer

We work by time and temperature to control the developer action. Not enough time, too low a temperature, and you get no pictures. Too much time, too hot, and you get a very black negative, hard to print, tones not good, and big grains.

Recommend buying a good thermometer

Developer

There are thousands of published formulae for developers, dozens of ones you can buy ready-made. Some are for negatives; some are for printing-don't get them mixed up.

I would encourage you to use Kodak D 76 to start with-- the materials to make it are downstairs, and it is a good film developer. All the new, expensive developers compare themselves to it, and it still comes through pretty well.

Time and temperature are about 7 minutes at 20 C (look up to make sure) Agitation is 5 seconds every 30 seconds

Stop Bath

About 50 mls of 28 % acetic acid per litre makes a good stop bath. 30 seconds to a minute, with agitation, will suffice

Fixer

The main ingredient of the fixer is Sodium Thiosulphate, about a 20% solution. However, preservatives and hardeners are also needed for film. You don't want the gelatin to peel off the backing: alum is used as a pickling agent (just like Bick's pickles). The formulae and ingredients are downstairs. I recommend the F 5 formula, or Kodak acid fix with hardener.

Hypo Clear

It is possible to cut down the washing time with some commercial products.

Check them out in a major camera shop (give examples)

Washing

It is necessary to get all the chemicals out of the gelatin-- 30 minutes to an hour is necessary in 20 C water.

A final rinse in a special, dilute soapy solution (photo-flo) is recommended to prevent water spots, caused by the chemicals in Toronto water. As an alternative, several rinses in distilled water can be used.

Drying

It is preferable to dry the film by hanging it up in a dust- free place. Clothespins and drying cabinets are provided downstairs. It is not a good idea to hang the film in the main corridor- dust and fingerprints often mysteriously appear.

Storage

When dry, the film should be cut into strips and stored in film storage envelopes. The clear plastic ones can be used to make contact prints, so you can see all the pictures on the film at once.

Part 3-- actual demonstration--- please ask questions if you don't understand anything-- like why I knock the tank on the table (to get rid of air bubbles on the film)--good luck-- try a roll-- you will like it.