The film gate is the rectangular opening in the front of a motion picture camera where the film is exposed to light. The film gate can be seen by removing the lens and rotating the shutter out of the way. The film is held on a uniform plane at a calibrated distance in the gate by a pressure plate behind the film.
Occasionally, as the film passes through the gate, friction can cause small slivers of celluloid to break off and stick in the side of the opening. These pieces of debris are called hairs. A "hair in the gate" will remain in front of the film and create a dark line that sticks into the edge of the film frame as the camera is filming a shot. A hair can ruin the shot and is almost impossible to fix in post production without using modern digital removal techniques.
Because of the intractability of this problem the focus puller (or 1st Assistant Camera) will open the camera and examine the gate for hairs at the end of each shot. Normally the assistant director will call out "check the gate" when the director is ready to move on to the next shot. The crew will wait until the focus puller calls out "gate is clean." If the gate is not clean, it will be cleaned with orangewood sticks and canned air and the crew will take the shot again. A good camera crew usually checks all cameras and magazines during equipment checkout with "scratch tests" using fogged film rolls — this will catch out any possible scratch or hair problems caused by faulty equipment. However, a variety of other factors including environment, humidity, type of film stock, camera position, film ridging, and lacing can each be responsible for a "hair in the gate". Generally, skilled crew and regularly inspected tested equipment make this a rare occurrence, and it is not unheard of for assistants to go for months without seeing one, even on large-scale shoots. The cinematographer Oliver Stapleton praised his assisting team on Casanova for not having a single hair or scratch for the whole shoot, even though large portions were shot on dusty exteriors. [1]
Video cameras do not have this problem, as any malfunction to the sensor will render the entire system useless. The Arri D-20 and D-21 system, however, does have removable lenses and a rotating optical shutter, which means that the CMOS sensor can be exposed in much the same way as a film gate and thus needs to be kept assiduously clean.
There are three different commonly accepted ways to check a film gate for hairs.
In this method, the lens is taken off of the camera and the shutter is moved either with an automatic button (usually labeled "phase" or "dust check") or by manually inching it to an exposed position. The focus puller examines the gate with a flashlight, sometimes attached to a magnifying glass.
This method tends to be most useful on long lenses and zoom lenses, especially when larger lenses may be difficult to take on and off again quickly. The aperture is fully opened, with the shutter opened, focus set to infinity, and if a zoom, zoomed in as tight as possible. The lens itself acts as a large magnifying glass for the focus puller, who only needs to position the flashlight and their line of sight properly to scan the gate.
Many cameras, though not all, allow for the gate itself to be removed from the camera and examined under a light by the focus puller.
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane.
A camera is an optical instrument that captures a visual image. At a basic level, cameras are sealed boxes with a small hole that allows light in to capture an image on a light-sensitive surface. Cameras have various mechanisms to control how the light falls onto the light-sensitive surface. Lenses focus the light entering the camera and the size of the aperture can be widened or narrowed. A shutter mechanism determines the amount of time the photosensitive surface is exposed to the light.
A digital camera is a camera that captures photographs in digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film. While there are still dedicated digital cameras, many more cameras are now incorporated into mobile devices like smartphones, which can, among many other purposes, use their cameras to initiate live video-telephony and directly edit and upload images to others. High-end, high-definition dedicated cameras are still commonly used by professionals and those who desire to take higher-quality photographs.
A view camera is a large-format camera in which the lens forms an inverted image on a ground glass screen directly at the plane of the film. The image is viewed and then the glass screen is removed and the film inserted in its place, and thus the film is exposed to exactly the same image as was seen on the screen.
In photography, shutter speed or exposure time is the length of time that the film or digital sensor inside the camera is exposed to light when taking a photograph. The amount of light that reaches the film or image sensor is proportional to the exposure time. 1⁄500 of a second will let half as much light in as 1⁄250.
A camera lens is an optical lens or assembly of lenses used in conjunction with a camera body and mechanism to make images of objects either on photographic film or on other media capable of storing an image chemically or electronically.
In photography and cinematography, a wide-angle lens refers to a lens whose focal length is substantially smaller than the focal length of a normal lens for a given film plane. This type of lens allows more of the scene to be included in the photograph, which is useful in architectural, interior and landscape photography where the photographer may not be able to move farther from the scene to photograph it.
In photography, bracketing is the general technique of taking several shots of the same subject using different camera settings. Bracketing is useful and often recommended in situations that make it difficult to obtain a satisfactory image with a single shot, especially when a small variation in exposure parameters has a comparatively large effect on the resulting image. Given the time it takes to accomplish multiple shots, it is typically, but not always, used for static subjects. Autobracketing is a feature of many modern cameras. When set, it will automatically take several bracketed shots, rather than the photographer altering the settings by hand between each shot.
The role of an assistant director on a film includes tracking daily progress against the filming production schedule, arranging logistics, preparing daily call sheets, checking cast and crew, and maintaining order on the set. They also have to take care of the health and safety of the crew. The role of an assistant to the director is often confused with assistant director but the responsibilities are entirely different. The assistant to the director manages all of the directors in development, pre-production, while on set, through post-production and is often involved in both personal management as well as creative aspects of the production process.
A point-and-shoot camera, also known as a compact camera and sometimes abbreviated to P&S, is a still camera designed primarily for simple operation. Most use focus free lenses or autofocus for focusing, automatic systems for setting the exposure options, and have flash units built in. They are popular for vernacular photography by people who do not consider themselves photographers but want easy-to-use cameras for snapshots of vacations, parties, reunions and other events.
A digital single-lens reflex camera is a digital camera that combines the optics and the mechanisms of a single-lens reflex camera with a digital imaging sensor.
The science of photography is the use of chemistry and physics in all aspects of photography. This applies to the camera, its lenses, physical operation of the camera, electronic camera internals, and the process of developing film in order to take and develop pictures properly.
A rotary disc shutter is a type of shutter. It is notably used in motion picture cameras. Rotary shutters are semicircular discs that spin in front of the film gate, alternately allowing light from the lens to strike the film, or blocking it.
Video assist is a system used in filmmaking which allows filmmakers to view and distribute a video version of a take immediately after it is filmed.
In photography, a shutter is a device that allows light to pass for a determined period, exposing photographic film or a photosensitive digital sensor to light in order to capture a permanent image of a scene. A shutter can also be used to allow pulses of light to pass outwards, as seen in a movie projector or a signal lamp. A shutter of variable speed is used to control exposure time of the film. The shutter is constructed so that it automatically closes after a certain required time interval. The speed of the shutter is controlled by a ring outside the camera, on which various timings are marked.
Bridge cameras are cameras that fill the niche between the single-lens reflex cameras (SLRs) and the point-and-shoot camera which are prominent in the prosumer market segment. They are often comparable in size and weight to the smallest digital SLRs (DSLR), but lack interchangeable lenses, and almost all digital bridge cameras lack an optical viewfinder system. The phrase "bridge camera" has been in use at least since the 1980s, and continues to be used with digital cameras. The term was originally used to refer to film cameras which "bridged the gap" between point-and-shoot cameras and SLRs.
Image stabilization (IS) is a family of techniques that reduce blurring associated with the motion of a camera or other imaging device during exposure.
The Panasonic Lumix DMC-GH1 is a digital mirrorless interchangeable lens camera adhering to the Olympus and Panasonic developed Micro Four Thirds System (MFT) system design standard. Panasonic classified the GH1 as a hybrid stills/video camera and the GH1 was introduced and marketed as a higher end camera than Panasonic's first MFT camera, the stills only, non-video capable Lumix DMC-G1.
The Pentax 645 is a medium format single-lens reflex system camera manufactured by Pentax. It was introduced in 1984, along with a complementary line of lenses. It captures images nominally 6 cm × 4.5 cm on 120, 220, and 70 mm film, though the actual size of the images is 56 mm × 41.5 mm.
The Pentax Q is a mirrorless interchangeable-lens camera introduced by Pentax on June 23, 2011.