NAS –  Network Attached Storage. Data storage technology that can be connected directly to a computer network to provide centralized data access and storage to heterogeneous network clients. Storage space is usually made available through regular network connections. Due to the standard interface technology it is relatively inexpensive, but does not deliver sufficient data rates for real-time HD or film transfer.

nc-17 –  also  nc-17, x-rated, x rated, x;  no one 17 and under admitted. A certificate issued by the MPAA indicating that no person aged 17 or under will be allowed to attend a screening of the movie. This category was formerly called “x”, but many people’s mistaken association of “x” films with xxx films caused the MPAA to change this on September 27, 1990.

ND filter  – neutral density filter. ND filters reduce the amount of incident light equally across the entire visible wavelength range without affecting color.

NEF – Nikon Electronic Format. Nikon’s proprietary raw image file format, sometimes shown as NEF (raw).

Ni-Cad or NiCad – Nickel Cadmium. Abbreviation coined and popularized by Saft America for lightweight camcorder battery type  designed to maintain power longer than traditional lead-acid batteries.  One type of rechargeable battery that should be completely discharged of its energy before it is recharged.

NG – also  no good. An abbreviation of the phrase “No Good”, which can be used to describe various aspects of film-making, i.e. “an NG take”.

NiMH – Nickel Metal Hydride. A NiMH battery is one type of rechargeable battery that does not need to be completely discharged of its energy before it can be recharged.

NLE –  Non-Linear Editing. This term describes a form of the editing process. Here, the recording medium is not a tape, therefore, editing can be performed in a non-linear manner, i.e. the editor is independent of the sequence of the program. NLE has the advantage of editing with quick access to source clips and record space (e.g. on computer disks). Moreover, it removes the need of winding and pre-rolling of VTR operations and hence speeds up work. Even greater speed and flexibility are  possible when real-time random access to any frame (true random access) is applied. The term NLE is mostly used when discussing offline editing systems storing highly compressed images, but increasingly online non-linear systems are available as well. Nowadays quite a range of systems claim online quality with video compression. Still, prospective users have to judge the suitability  of the results for their application and bear in mind that for transmission & distribution the signals will be decompressed and re-compressed again.

NTFS –  an acronym for Microsoft Windows “New Technology File System”. It is a file system from windows, used for storing and retrieving files. It allows data security on fixed and removable disks.

NTSC –  National Television Standards Committee group formed by federal communications commission to regulate U.S. television broadcasting specifications, created this first international television system for use in the U.S. and other countries. In 1941, the U.S. committee developed a standard for encoding analog monochrome (black and white) video and audio television signals. Basically, the standard specifies line count, image refresh frequency, synchronization, modulation schemes, and composite signal encoding. The NTSC standard was augmented in 1953 to enable color television as well as monochrome. The American system of color telecasting is used mainly in North America, Japan, and parts of South America. NTSC television uses a 3.579545 mHz subcarrier whose phase varies with the instantaneous hue of the televised color and whose amplitude varies with the instantaneous saturation of the color. NTSC employs 525 lines per frame and 59.94 fields per second. It produces pictures by creating 525 alternating lines across the TV screen for each frame of video. NTSC refers to all video systems conforming to this 525-line ~30-frame-per-second signal standard, image format is 4:3 aspect ratio, 60 hz and 4 mHz bandwidth with a total 6 mHz video channel width. Since PAL and SECAM, the other two world systems, were developed later, they took advantage of better technology. Insiders joke that NTSC means “Never The Same Color” .

Nagra –  a professional ¼-inch audiotape recorder.

nanometer –  the unit of measure for a wavelength of light. One billionth of a meter.

nanosecond (nsc) – one billionth of a second. An indication of the precision required in the timing of video signals.

narrow lighting – also called “short lighting,” narrow lighting is arrived at when the main light completely illuminates only the side of the subject’s face that is turned away from the camera.

native material – certain video systems such as digital disk recorders or VTRs can only be configured to accept one video format a time. With VTRs the dependence on a definite video format is determined by the format of the used tape. With digital disk recorders it may depend on the format of the recorder’s storage. This is then called the native material or the material native to the device.

native resolution – the number rows of horizontal and vertical pixels that create the picture. The native resolution describes the actual resolution of the imaging device and not the resolution of the delivery signal.

natural light – planetary illumination, from sun, moon, stars, be it indoors or out. Has higher color temperature than artificial light, and thus more bluish qualities.  See artificial light, color temperature.

naturalism –  a type of lighting that follows natural (realistic) patterns and angles.

near-field   sound that has not been colored by room reflections. this is also known as direct sound.

near-line –  intermediate type of data storage, i.e. the on-site storage of data on removable media. It is a compromise between on-line storage (very quick to access) and off-line storage (mostly backup or long-term storage). Near-line storage provides reliable, inexpensive and unlimited data backup and archiving, but with less speed and accessibility than with integrated online storage.

nearest neighbor – interpolation type in which the value of a newly-created pixel is copied from the nearest pixel.

negative –  an image in which the brightness values are reversed, that is, reproduced so that the lightest areas are the darkest, the darkest areas are the lightest, and intermediate tones are similarly reversed, in either black-and-white or color.  Black and white films appear gray or purplish, and color films have an overall orange hue.  1. the raw stock specifically designed for negative images. 2. the negative image. 3. negative raw stock that has been exposed but has not been processed. 4. processed film bearing a negative image.

negative cost  – the cost of a movie through the production of a finished negative, not including the costs of prints, advertising, or distribution.

negative cutting –  process of cutting and splicing the original negative to match the final edited film.

Negative Cutter – a person who matches the negative of a movie and conforms (matches) it to the final version of the film as decided by the filmmakers. From this negative the prints are made.

negative holder – a clamp-like device that fixes a negative in position in an enlarger.

negative image – a photographic image in which the values of light and shade of the original photographed subject are represented in inverse order. Note –  in a negative image, light objects of the original subject are represented by high densities and dark objects are represented by low densities. In a color negative, colors are represented by their complementary color.

negative pickup – an agreement where a distributor acquires a finished negative and agrees to pay distribution and other  costs, as opposed to deals where the distributor is involved during production.

negative print –  a reverse light image capture. See also positive print.

negative perforations –  a generic term for the Bell And Howell perforation.

negative-positive process –  1. photographic process in which a positive image is obtained by development of a latent image made by printing a negative.        2. any photographic process in which a negative is first made and then used to produce a positive image (e.g. a print)

negative ratio – the aspect ratio of the negative used to shoot the film

negative timing – or negative grading. The selection of the appropriate color correction(timing lights) for the printing process.

network – 1. the affiliation of television or radio stations such as ABC, CBS, NBC, CBC, BBC, etc. 2. a combination of electrical elements, such as a group of interconnected computers. 3. an interconnected system of computers and storage devices. Computers in a network are able to work together to perform processes and share data.

neutral-density filter – mounted at front of camcorder lens, reduces light intensity without affecting its color qualities.  Absorbs all visible wavelengths to a more or less equal extent. ND filters can be used with digital cameras and both monochrome and color films, since they have no effect on color balance. See filter.

neutral test card – also known as the  gray card  or a “Kodak neutral test card,” this is typically (but not necessarily) an 8″ x 10″ (20 cm by 25.5 cm) card, about 1/8″ thick, that is uniformly gray on one side. The gray side reflects precisely 18%  of the white light that strikes it (corresponding to the calibration of a reflected-light meter). It is uniformly white on the other side, which reflects 90% of the light. A gray card can be very useful in determining proper exposure.

new deal – changing setup, either for a new camera position or a new scene.

Newton’s rings –  1. fuzzy, faintly colored lines in the projected image caused by high or uneven printer gate pressure.  2. color spots that may appear on slides mounted between glass surfaces, caused by contact of the smooth glass surface with  the smooth film base.

nit – the metric unit for screen, or surface brightness.

nitrate film – the earliest film base, manufactured before 1950. This film must be handle carefully to prevent spontaneous combustion. Nitrate film is highly flammable when stored in improper conditions and was replaced by acetate stocks by 1951. It has not been domestically manufactured since around 1950.  It is still present in large quantities in storage vaults and archives and must be very carefully stored to prevent explosions.

no single point of failure – describes a configuration in which at least one of each component may fail without losing the functionality or data of the system.

nodal point – optical center of a lens.

noise – 1. unwanted disturbance within an electronic system; interference present in a video picture; undesirable video or audio signal interference; typically seen as snow, heard as hiss. 2. any unwanted signal interfering with the clarity and intelligibility of desired signals. 3. The background of static inherent in any recording or amplifying device, generally forty to sixty dB below the peak output level of the device.  4. random errors and fluctuations in an image. Noise can be distracting across a sequence of frames. 5. the grainy look you find in a digital image caused by image artifacts. It may also appear as flecks of color that should not be there. it is usually noticeable in shadow areas, and generally produced when shooting in low light. it is caused by high ISO required for low light shooting. Noise is almost always unwanted and unattractive.

noise floor – a level or amplitude representing the amount of near-continuous background noise present in the signal. Abackground hiss would raise the noise floor, and could prevent a faint signal (one below the noise floor) being heard at all. Unwanted sporadic noise such as a member of the audience coughing is noise, but it doesn’t contribute to the noise floor.

noise reduction – 1. in some cameras, noise reduction can be activated or switches on automatically at slow shutter speeds. Note that noise reduction often requires more time for the photo to be written to the memory card, during which you will be unable to take a picture.   2. electronic reduction of observable grain in the picture.   3. Reduces constant background noise such as fans, tape noise, or hums. It will not work for removing talking or music in the background.  Noise reduction can reduce constant background sounds such as hum, whistle, whine, buzz, and “hiss”, such as tape hiss, fan noise or FM/webcast carrier noise. It is not suitable for individual clicks and pops, or irregular background noise such as from traffic or an audience. Be aware that it may be impossible to get a satisfactory removal when the noise is very loud,  when the noise is variable, when the music or speech is not much louder than the noise or when the noise frequencies are very similar to those of the music or speech. If your problem is mains hum or a high-pitched whistle, the use of a notch filter may help, which should be carried out before applying noise reduction.

non-drop frame – 1. a type of SMPTE time code that continuously counts a full 30 frames per second. as a result,  non-drop-frame time code does not exactly match real time.  2. System of time code that retains all frame numbers in chronological order. See also drop frame.

noninterlaced video – process of scanning complete frames in one pass, painting every line on the screen, yielding higher picture quality than that of interlaced video. Most computers produce a noninterlaced video signal; NTSC is interlaced.  See interlaced.

non-lens spotlight – a light with variable field and beam angles obtained by changing the spacing between the bulb and reflector.

non-linear editor/editing – 1. an editing system based on storage of video and audio on computer disk, where the order or lengths of scenes can be changed without the necessity of re-assembling or copying the program. 2. Digital “cut and paste” editing that uses a hard drive instead of tape to store images. Random access allows easy arrangement of scenes in any order. Also eliminates the need for rewinding and allows for multiple dubs without generational loss.  3. The computer-assisted editing of a movie without the need to assemble it in linear sequence; the visual equivalent of word processing. 4. Flexible form of editing where shots can be edited in a manner that do not conform to, or affect, the planned story order. 5. Editing of video and audio on a computer.

normal (surface normal) – a three-dimensional vector which is perpendicular to a surface. Central to many computer graphics calculations.

normal lens – also termed a standard lens, a normal lens has a focal length approximately equal to the diagonal of the film format or of a digital camera’s image sensor. A scene viewed through a normal lens appears to have the same perspective as if it was being viewed  normally  without a lens, just the way your eye sees it. A normal lens is neither a wide-angle (short)  nor a telephoto (long) lens. Most 35mm cameras’ normal lenses have a focal length of approximately 50 mm. See lens selection for info on standard and other lenses.

normal mapping – an application of the technique known as bump mapping. While bump mapping perturbs the existing normal (the way the surface is facing) of a model, normal mapping replaces the normal entirely. like bump mapping, it is used to add details to shading without using more polygons. but where a bump map is usually calculated based on a single-channel (interpreted as grayscale) image, the source for the normals in normal mapping is usually a multichannel image (with red/green/blue channels) derived from a set of more detailed versions of the objects.

nonsynchronous sound – audio without precisely matching visuals. Usually recorded separately, includes wild sound, sound effects, or music incorporated in post-production. See synchronous sound.

nonvolatile – a memory system whose stored data is undisturbed by removal of operating power.

normalize –  to boost the level of a waveform to its maximum amount short of clipping (distortion). This maximizes resolution and minimizes certain types of noise.  normalize increases a waveform s level to its highest before it becomes distorted.

notch filter – a notch filter is a band-stop filter with a narrow stop-band (high q factor), which notches out, or eliminates, a specific band of frequencies.

nuvicon – a type of video pickup tube used in inexpensive color television cameras.

Nyquist frequency – the highest frequency that can be reproduced accurately when a signal is digitally encoded at a given sample rate. Theoretically, the nyquist frequency is half of the sampling rate. For example, when a digital recording uses a sampling rate of 44.1khz, the Nyquist frequency is 22.050khz. If a signal being sampled contains frequency components that are above the Nyquist limit, aliasing will be introduced in the digital representation of the signal unless those frequencies are filtered out prior to digital encoding. See aliasing, brick-wall filter.

Nyquist rate – Named after Harry Nyquist. The sampling rate required to convert an analog signal into a digital signal. The sampling frequency must be greater than twice the bandwidth of the input signal to perfectly reconstruct the original. Not to be confused with Nyquist frequency.

Nyquist rule –  states that in order to be able to reconstruct a sample signal with out aliases, the sampling signal must  occur at a rate of more than twice (2x) the highest desired frequency. This rule is usually observed in digital systems. A frequency lower than this rate is called an “alias”.