Film Formats (only in our collection).The primary characteristic of a film format is its size and shape:
- 9, 5 mm - Film width 9, 5 mm, image size 6, 5 x 8, 5 mm. The 9.5 mm film is an amateur film format introduced by PathÃ© FrÃ¨res in 1922 as part of the PathÃ© Baby amateur film system. It was conceived initially as an inexpensive format to provide copies of commercially made films to home users. The format uses a single, central perforation (sprocket hole) between each pair of frames. Silent and sound format.
- 8 mm (standard or known as regular 8 mm); silent and sound format.
-Super 8 mm (a larger image area because of its smaller perforation); silent and sound format;
- 16 mm (sound format with soundtrack), extensively used in WWII and after, in fields: educational, governments, business, industrial, medicine;
- 35 mm - 35 mm film is the basic film gauge most commonly used for motion pictures, and remains relatively unchanged since its introduction in 1892 by William Dickson and Thomas Edison. The photographic film is cut into strips 35 millimeters (about 1 3/8 inches) wide. The standard negative pull down for movies ("single-frame" format) is four perforations per frame along both edges, which makes for exactly 16 frames per foot
Film gauge defines film width, traditionally the major film gauges in usage are: 9, 5 mm, 8 mm, 16 mm and 35 mm.
A film base, it is a transparent substrate which acts as a support medium for the photosensitive emulsion that lies atop it in numerous layers. In photographic terminology, the emulsion is the light sensitive coating supported by a base of cellulose nitrate or acetate which together form film. Historically there have been three major types of film base in use:
- Nitrocellulose – flame able (cellulose nitrate);
- Cellulose acetate (cellulose triacetate);
- Polyester (polyethylene terephthalate) – PET; Kodak trade-name: ESTAR.
Types of films: two main types of film are available: negative and reversal.
- Negative film producing negative image when it is developed in which black are white, white are black.
- Reversal film produces a positive image when it is developed, and a camera original can be projected without making a print. The best example of it is super 8 mm home movie film or slide film.
Film speed is the measurement of film accumulation sensitivity to light. The film speed is named as EI – Exposure Index, or: ISO – International Standard Organization; ASA – American Standard Association; DIN – Deutsche Industries Norm. The lower EI number requires more light to obtain an exposure and is called slow film, the higher EI number requires less light to introduce film is called fast film.
Sprocket -Sprockets are used in the film transport mechanisms of movie projectors and movie cameras. In this case, the sprocket wheels engage film perforations in the film stock. Feed Sprocket - A driven sprocket which feds film from a compartment or magazine into a piece of mechanism such as camera, projector or sound camera. Take-up sprocket - A driven sprocket which moves film out of piece of film mechanism and into magazine or onto a spool at the completion of a process.
Claws – the mechanism for transporting and to held the film precisely in place during exposure. The most popular are five types of film movements: Oscillating claws; Bolex double claws; Arriflex II; Mitchell movement and Bell & Howell movement.
More about on web site: http://www.sci.fi/~animato/movements/movements.html
Notched - The projection system is incorporated a way to save film on nonmoving titles. A notch in the film is recognized by the projector which would then project the frame for 10 seconds. By this method, 10 seconds of screen time was available for 1 frame of film, rather than the 140 frames required if the film was projected at the normal rate.
Fps – the number of film frame per second.
Filming speed: 8; 16; 24; 25; 32 fps
Turret lens – a rotating device on a camera for bringing any of several lenses in front of the shutter.
Viewfinder - An optical device forming part of a camera, or attached to it, which provides an image (usually magnified) approximating that which is formed by the lens on the film. Our cameras have two types of viewfinders: optical viewfinder or reflex viewfinder (reflex mirror at 45 degree angle).
Optical viewfinders- are built into the body of the camera. They show a reduced image of the subject. Two small marks indicate the framing for close range work where the effect of parallax is most apparent.
Reflex viewfinders- by means of a tiny mirror (or silver paint - Arriflex camera) in the light path, provide a view of the subject through the actual taking lens. So image size, focus, and framing are seeing exactly as on the film
Parallax error – arises because of the different position of viewfinder and taking lens. This difference is not noticeable when shooting at normal or long ranges. But when the subject is very close to the camera the viewfinder covers a slightly different area from that of the taking lens. The effect of parallax may be most easily seen by looking past a near object at a far object with the left and right eye alternately, the other eye being closed.
Aperture - is a hole or an opening through which light travels. The aperture lens can be adjusted to control the amount of light reaching the film. In combination with variation of shutter speed, the aperture size will regulate the film's sensor's degree of exposure to light. Typically, a fast shutter speed will require a larger aperture to ensure sufficient light exposure, and a slow shutter speed will require a smaller aperture to avoid excessive exposure. The lens aperture is usually specified as an f-number, the ratio of focal length to effective aperture diameter. A lower f-number denotes a greater aperture opening which allows more light to reach the film or image sensor. The specifications for a given lens typically include the minimum and maximum apertures, such as for example f/22 - f/1.4. In this case f/22 is the smallest or minimum aperture opening, and f/1.4 is the widest or maximum aperture. Aperture values wider than f/2.8 are typically known as "fast" lenses. The fastest lenses in general production are f/1.2 or f/1.4, with more at f/1.8 and f/2.0, and many at f/2.8 slower.
Shutters - which exposes the film frame by frame to the light:
Telephoto lens is a specific type of a long-focus lens in which the physical length of the lens is shorter than the focal length.