4”x5” is the smallest film size that most people consider to be “large format.” 4”x5” film comes in a variety of forms, including color negative, color positive, black and white positive and negative and various Polaroid forms. Not all emulsions are manufactured in 4”x5” format, but most “professional” emulsions are. Sheets can run from $.30 a piece to quite a few dollars per sheet depending on the type and vendor but $1 a sheet is a common average estimate.
4”x5” film is usually sold in a light tight box, packaged in a foil pouch. Most of the foil pouches hold 25 sheets and a box will usually have one, two or four pouches in it. Some films are sold in alternate packaging, usually with the aim of removing the hassle of dealing with boxes full of pouches full of individual sheets that can only be handled in the dark. For example, Kodak has a system called “Readyload” that uses a special back and single sheets. Fuji’s equivalent is called “Quickload.”
Most black and white sheet film has notches cut on one side of the short side. These notches are intended to be used to determine the speed and type of film in the dark but are most useful for determining which way the film is facing. If a sheet is laying vertically and the notches are on the top right or bottom left of the film, the emulsion is facing up. Otherwise it is facing down. This is important to know when you’re loading or developing the film. If you load the film with the emulsion facing away from the lense, the light has to go through the film base before is exposes the film.
In general, you don’t just grab a sheet of film, stick it in your camera and shoot it. It takes a little more preparation than that. You have to use film holders. These are reusable thin boxes, usually made of plastic or metal. They’re slightly larger than 4”x5” film and usually a little longer than would be proportional. The basic principle behind them is having a light tight box that you can insert into the back of a camera with a window that can be opened when you want to expose the film. This is accomplished by means of a dark slide, which is inserted at one end of the film holder and slides all the way down to cover the negative and seal it off from light. Most negative holders are double sided, so you can have a sheet of film in each side to reduce the number of film holders that you have to carry around.
Most dark slides have a light side and a dark side. There is no universally accepted way of using them, but most people chose one side to mean “unexposed” and the other side to mean “exposed.” Then, when they take out the dark slide to take a picture, they turn it around before putting it back in. That way, they know that sheet has been exposed and don’t accidentally double expose it.
Since the film needs to be loaded into the film holder in darkness, people who shoot 4"x5" in the field usually carry a changing bag with them. A changing bag is like a little portable darkroom that you stick your hands in. That way, once they've exposed all of the film they have loaded, they can unload their film holders inside of the changing bag and then reload them with unexposed film without having to go back into their darkroom before they can shoot more. Changing bags can range from a relatively cheap rubberized nylon bag to a fairly expensive neoprene coated tent with internal supports and a reflective silver exterior to help moderate the temperature.
4”x5” film is used almost exclusively in view cameras. Technical cameras, field cameras and studio cameras all tend to use 4”x5” negatives (or larger.) Most of these cameras have a sheet of ground glass in the back that the image to be photographed is projected on. The ground glass usually has some sort of spring/hinge system that lets a negative holder slide in front of it (so that the film is in the same place the ground glass was before.)
Developing 4”x5” Film
Like most things in photography, developing 4”x5” can be done by a professional lab. However, one of the advantages of using sheet film is the ability to process each exposure individually to get the best negative possible. Not to mention that processing your own film is fun, in an obsessive-compulsive/masochistic kind of way.
There are three primary ways of developing 4”x5” film. There is tank developing, daylight tank developing, and tray developing.
In tank developing, the chemistry is set up in open tanks, lined up in order. This method must be done without any light until the film has been fixed.
In total darkness, the negatives are inserted into “hangers” that allow you to immerse the film in the chemistry while keeping your hands dry. To agitate, you lift the hangers out of the tank and allow to drain briefly before reimmersing. In tank developing, you agitate in this manner around once a minute for the duration of development.
Tank developing is the only method listed here that doesn’t require constant agitation. Some photographers have something approaching a religious conviction regarding the good effects of letting the chemicals settle at some point during development, so this is a popular option.
Daylight Tank Developing
Daylight tank development is similar to the technique used in processing black and white 35mm film. The sheets of film are placed into some sort of light-tight container that has some mechanism of adding or removing chemistry without fogging the film. There is an incredible variety of systems for doing daylight tank development, from simple hand agitated tanks to fully mechanized Jobo drum systems. The details of developing using daylight tanks depends on the specific equipment you want to use.
Tray developing is similar to tank developing in that it must be performed in the dark and requires you to set up you chemistry in a line. In tray developing, you set up everything in shallow trays. To immerse the negatives, you just place them in the tray and hold them off of the bottom with your fingers. To agitate, you simply slide the bottom sheet out from under the other sheets and place it on top, then push the stack down. When you’re done with one chemical, you just pick up the negatives, let them drain for a minute, then put them in the next tray.
Tray developing requires very little investment if you’re already processing your own black and white 35mm or 120 film. Unlike tanks and hangers and all of that, a set of four 5”x7” trays can be had for between $5 and $10, new. It’s the method where the failure of some little bit of metal or plastic is the least likely to mess up your negatives. On the other hand, it’s also the method where you’re the most likely to mess up your own negatives yourself. If you don’t agitate the negatives correctly, you can scratch them up horribly, develop them unevenly, stick them together or otherwise ruin them. Not to mention the fact that you have to submerse your hands into your development chemistry. This isn’t a big deal for most people with black and white processing, but the chemistry for other processes (like C-41) the chemicals involved are much more toxic.