FEATURES - Cinematography

Cinematography page 5

Even when kept in perfect storage conditions it is advisable to use the film within six months of purchase. If traveling abroad it is worth remembering that most stock manufacturers offer a service of payment in your home country and collection from the nearest agent to the location. In this way the DP is at least assured that no deterioration by any means has occurred before the shoot has begun.

The actual speed of the film will have an effect on the rate of or susceptibility to various kinds of damage. This is particularly true of x-ray radiation where the more sensitive the film is to visible light the more sensitive it will be to x-rays. When shipping undeveloped film stock great care must be exercised to reduce the amount of x-ray radiation the stock is subjected to.

If the film crew has to travel with the film stock it is advisable to carry it on the plane. Checked baggage that goes in the hold may receive far more radiation than hand baggage and film can be completely ruined. It is best to assume there is no such thing as a film-safe x-ray machine, although many will display this message. It is often possible to ring the customs department in advance and inform them a crew will be coming through; asking them for their co-operation when the crew gets to the barrier.

The effect of x-ray radiation on film is cumulative. That means that the more offer it is x-rayed the more the x-ray exposure will build up until it reaches the level where it is noticeable within the image. Therefore a crew traveling through several airports before having the film processed should try and get them all to hand-search the film stock. It can be very tedious but this greatly reduces the chance of any noticeable x-ray fog on the negative.

As to deterioration through excessive temperature and humidity, avoiding problems is all a matter of common sense. If a crew is filming in parts of the world where they may encounter a problem, any photographic shop specializing in darkroom equipment will sell a robust thermometer and hygrometer at very little cost. 

This can be used to keep a check on matters. In extremely hot conditions negotiations may be made with the hotel chef to put the majority of stock in the fridge. A good quality cool bag should be used for the stock needed that day only. 

It is most important that any film that has been in a fridge come up to room temperature before loaded into the magazine. If this is not allowed, condensation will form. If the nights are reasonably cool then the film should be taken from the fridge late in the evening and placed in a cool bag first thing in the morning.

However careful the DP is while traveling, they should always have the film processed as soon as possible after exposure. If they are really worried about any adverse effects, they may even have the film processed in the country they are working in.

Sensitometry, as the word would suggest, is the technique we use for measuring and evaluating the sensitivity of a film emulsion to light. The important part of the evaluation, to cinematographers, is to know how much light arriving at the emulsion is needed to produce the required density of image on the film after development. 

The relationship between the amount of light, the exposure, and the darkening, the density, will not be in the same ratio over the entire range of brightness recorded on the film. This is important for in creating the mood of the final picture. 

The cinematographer should be very concerned to know how much detail will be seen in the shadowed part of the image. Particularly if outdoors, they will wish look for details that can be recorded in the highlights of the scene so as to know how sky, sand, snow, etc. will be represented in the picture. 

In cinematographer Vilmos Zsigmond's opinion, lighting is the most important tool for the cinematographer. "Lighting creates mood. The mood places the audience into the story. You laugh. You cry. You feel happy. You feel sad. This is done by us- cinematographers- mainly with lighting."

This is his time of experimentation- a time that helps set his style of shooting, of pushing the limits. It is all about how he relates to lighting. "In Hungary, the DP lights and handles the camera," he says. "Not so, here. There, you have everything- you are controlling the look of the images, the way the camera moves- just one person, not two or three. The cinematographer is a very strong colleague of the director, so much so that the cameraman/cinematographer, in Europe, is 50% partner with the director. Sometimes, the DP will take over some of the director's problems."

Another characteristic the cinematographer needs to be aware of is the relative contrast of the film in use. Contrast and gamma are often confused. Gamma is a measurement of the rate of change of the exposure/density relationship. Contrast refers to the brightness range and the gradation between the highlights and the shadows; it is therefore expressed as a ratio. The contrast range that can be shown on a first-class cinema screen is the equivalent of seven stops of exposure. 

Recently developments in the construction of camera negative emulsions have made it possible to manufacture a negative able to record the equivalent of ten stops of brightness; this gives the film a contrast ratio of an incredible 1024:1. Cinematographers must learn to recognize the difference between contrast (as it is expressed as a ratio) and apparent contrast (as a 'soot and whitewash' image).