What is Film?
Film is a thin flexible strip of plastic or other material coated with light sensitive emulsion to expose in the camera. This is then used to produce photographs or motion picture.
Here is two different pieces of film, the top piece of film is undeveloped film (that has been exposed to a lot of light), while the second piece is a film that has been processed in the darkroom into a negative.
What kind of black and white film?
With a film camera, you not only have to consider what lenses you will use on your shoot (whether it be studio or location) But what film you will shoot with. Today modern DSLR have a wide ISO Sensitivity range, however not all DSLR’s are graced with such luxuries. This is where a film SLR used to be able to outpace first generation DSLR’s as you could use different ISO film to shoot with to suit your need. Where as DSLR’s can only shoot within the ISO sensitivity the manufacture specifies.
As technology has progressed however this is no longer a limitation for digital cameras, with some being able to surpass the sensitivity of what is possible with film.
However unlike a DSLR, when choosing a film based on ISO you have other things to consider such as: the Grain, the contrast of the film and the exposure latitude.
Exposure Latitude: is the extent that the photographic film can either be underexposed or overexposed to still achieve an acceptable exposure. In film photography the exposure latitude generally increases with the film ISO speed, but this isn’t always the case. However in digital photography, exposure latitude is the opposite.
Film Grain: When you have a lower ISO film the grain is much smaller and generally is more detailed than higher ISO films. This is because at higher ISO the grains are bigger and there are less to allow the film to capture more light. But this means there is less detail captured on the image, however with a lower ISO film the grains are much smaller and more detailed but need more light to expose.
What is the Darkroom?
When shooting with film, to process the film you have to use a darkroom. A darkroom is a room designed to process Photographic film and Photographic paper, because these rooms are designed to be dark as the materials used are light sensitive. Darkrooms have been in circulation since the early 19th Century ( what could be considered the advent of photography)
When making black and white prints, a safelight can be installed within the room to illuminate the work area. The safelight can only be used when making prints processing black and white film and colour film both have to be done in complete darkness. When making colour prints however there must be no light at all as this will affect the print.
Items that could be found in a Darkroom:
Film Developer is used in the processing of photographic films, plates or photographic paper. Film Developer converts a latent image into a visible image.
Ilford Ilfotec HC is a highly concentrated liquid developer, for processing all purpose black and white film. It can also be used in the film processing systems; using the right dilution.
Ilford Perceptol is a professional developer or an extra fine grain film developer, which gives excellent image quality. Ilford Percepetol is used for very fine grain film and speed is not important but optimum results in image quality are.
Stop Bath – a chemical bath that is usually used in processing traditional black and white photographic films, photographic paper and plates. This is used after the photographic material has been put in the developer to halt the developer, developing the negatives.
Stop baths normally contain an acetic acid as most developers are organic alkaline solutions, this neutralizes the reaction on the photographic paper. Stop Baths can cause chemical burns to some uses but the acid is normally diluted with a working solution.
Photographic Fixer is a mix of chemicals usually containing some sort of sodium chloride (salt), Sodium Thiosulfate is a popular choice in a fixing agent or ammonium thiosulfate commonly used in modern rapid fixer formulae. The fixer stabilises the image, removing the un-exposed areas of the photographic material (silver halide). By fixing the photographic material is no longer sensitive image.
Wetting Agents are used when the water consistency is hard and has the possibility to leave marks on the processed films. The water consistency becomes softer (reducing the surface tension of the water) allowing the film to dry without marks left on the film.
Ilford Wash-Aid can be used instead of water (and possibly a wetting agent being added to it). Ilford wash-aid is a hypo-eliminator to help the removal of the thiosulphate by-products of fixation using the process of ION Exchange. It is particularly useful with fibre bade papers as they have a greater chance of chemicals latching on.
Selenium Toner is a processed that is used to increase print performance and reduces fading. Selenium Toners are single solution toners that will partially convert the original silver (metallic silver) to silver selenide (purple–brown tone).