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p r o c e s s i n g f i l m at h o m e
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A brief introduction
For those who wish to try out, experiment with, or even use regularly, their older roll-film cameras, the costs and inconvenience of getting the film processed can be a major stumbling block. The average mini-lab is solely geared to 35mm and Advanced Photo System processing, so one has to resort to specialist labs, often via mail, with it's associated delays. Add to that the extra costs of "hand processing", which often seem to be associated with conventional black-and-white film, and the whole idea becomes less attractive.
With the availability of relatively cheap high-resolution flat-bed scanners with transparency hoods and photo-quality printers, the concept of the old-fashioned "wet" darkroom is almost unnecessary. No longer is there a need to dedicate space for an enlarger and trays of chemicals, as once the film itself is developed, everything else can be conducted in the comfort of the home-computer environment.
This page is designed to be exactly what the title says, a brief introduction, to encourage those who are "thinking about it", or possibly never even considered the idea, to look into it in more detail. I am not going to write an illustrated tutorial on the subject. There are many books available, read in conjunction with the instructions for your particular developing tank, that will demonstrate the procedures far more effectively than I could hope to achieve. Pictures and detailed descriptions of the specific equipment I use would only serve to confuse those whose tank etc differs from my own. Similarly there are web sites dedicated to achieving high-quality scans from film negatives, Wayne Fulton's site being a prime example.
The processing of conventional black-and-white film has been conducted by amateurs for at least 100 years. The basic procedures haven't changed much, but the implementation, using "modern" equipment, is very straightforward.
The equipment needed comprises :
- A developing tank. Usually a cylinder with a light-proof screw-on lid, about 4-6" in diameter, 6" or more tall, containing a spiral to load the film into. These do differ in design, but the principles are the same. There is a light-trapped aperture, usually funnel-shaped, through which the chemicals are introduced into the tank and poured back out as necessary. If buying second-hand ensure that the instructions are supplied and that in any case the tank and spiral are suitable for the size(s) of film you wish to process. Some tank/spiral combinations are one-size only, others have adjustable spirals, usually for 35mm, 127 and 120/620 film. 828 film will fit into a 35mm spiral, as will 126 Instamatic. If you are considering anything wider, 116/616 for example, you will almost certainly have to shop around for a second-hand item. At least one manufacturer used to produce a separate spiral for 16mm film, also suitable for 110 Instamatic. Consideration of potential future requirements may influence your initial purchase.
- A thermometer that is accurate at 68F (20C).
- A graduated measuring cylinder or jug (plastic or glass, not metal) to hold sufficient liquid for your tank/film combination, (two or three of these are more useful, but not absolutely necessary).
- A smaller graduated cylinder (50cc), capable of measuring to 1cc increments, may be needed if preparing chemicals from concentrate.
- Two or three storage bottles to keep the part-used chemicals for next time.
- A funnel to fill the bottles.
- A timer with a second-hand. A wristwatch is fine, though a stopwatch is easier to use.
- A pair of film clips for drying the film. One of the pair is usually weighted to hold the film straight, though no doubt "Bulldog" clips, clothes pegs etc. could easily be adapted to suit.
Most, if not all of this hardware will be found very economically second-hand at on-line auctions such as eBay, in private advertisements in photographic magazines, or even occaisionally in second-hand shops, flea-markets etc. The total outlay, if purchased second-hand, will probably be recouped after very few films, discounting the immediacy of having your negatives to hand and the satisfaction of having done it all yourself.
Chemicals comprise developer and fixer. A "stop bath" is nice to have but not absolutely necessary. Choice of developer is primarily dictated by the suitability for the film(s) you are using. The instructions that came with your film will usually recommend one or more developers with appropriate development times, dilutions etc. The instructions that come with a developer may not include the specific film your are using, so take the recommendations of the film manufacturer and purchase to suit. Most conventional black-and-white film will include a recommendation for Kodak D.76 or Ilford ID11 developers. These are effectively the same formulation and can be used interchangeably. Available in powder form, (so lightweight if ordering by mail), these developers are an "industry standard" and have good shelf-life if stored as directed. Many other developers are available with varying degrees of "fine grain", "improved acutance" and/or "increased film speed" capabilities. Most, if not all, are very good, but if the film you wish to process is not covered by the manufacturer's instructions, they are of little use. Fixers are usually "universal", suitable for both films and prints, and as such there is little to choose between them, though some are "rapid" and may save a few minutes processing time.
The processing sequence, in brief, is as follows :
- The film is loaded into the tank and the tank sealed. This needs to be done in total darkness and is the only "tricky" bit. Procedures and techniques do vary between different manufacturers' and style of tank, but once you've got the knack for your equipment it should be easy enough.
- Then, back in the light, the developer is poured into the tank for an appropriate time (usually only a few minutes) and agitated as per the directions. The developer temperature is important, usually 68F (20C), so if the room temperature differs significantly from this the tank is usually kept in a container of water at 68-70F (20-21C) during this process. Agitation can comprise either inverting the tank so many times every so many seconds, (once every 30 seconds, three times every minute or whatever), or rotating the spiral back and forth within the tank using the rod provided for the purpose, again at the defined time interval.
- The developer is then poured back out of the tank and the film, still sealed in the tank, given a quick rinse in water or "stop bath".
- Having poured this out, the fixer is poured into the tank for a few more minutes, agitated as per the directions and poured back out.
- Next the film, still in the tank, is washed for 15-30 minutes in running water or multiple changes of clean water.
- Finally remove the film from the tank, hang it up to dry with the clips, in a dust-free space, and there are your negatives ready to be scanned.
Yes, it really is that easy. If you follow the manufacturers' instructions to the letter there are no hidden pitfalls, though 120/620 size film, by virtue of its width, tends to be a bit flexible, so can be slightly more difficult to load into some spirals than, say, 35mm film. You may wish to sacrifice a roll of film to use for loading practice in daylight before going "live". Outdated film is probably best (and cheapest) for this, and may well be available from wherever you source your chemicals.
Having become familiar with the requirements for processing film following a standard procedure, you will be free to experiment with different speeds of film in different types of developer to produce good negatives that may have been taken in less than optimum conditions. Having the ability to re-rate film to a different speed, then process it to produce an adequate negative, is one of the great advantages of home processing. Similarly, "clip tests", where just a short length is cut from a film and processed for evaluation, can be very useful when trying to establish how well (or not) an old camera is functioning. Several clip tests may be necessary to establish a correct set of parameters for a specific camera and film combination, but only one roll of film need be sacrificed to achieve this.
All of the above has referred to "conventional" black-and-white film. This therefore excludes the "chromogenic" black-and-white films such as Ilford's XP2 or Kodak's T-Max T400 CN, which use colour chemistry. The procedures for colour negative film are virtually identical, though timing and temperature control are rather more critical, and, obvio
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