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Digital Cinema Production and Post TECHNICAL TERMS

Sensor Dimensions: The height and width of a sensor, measured in inches, millimeters and/or pixels.

S35: Super 35mm. Sensor dimensions equivalent to a 3-perf, 16:9 frame of 35mm film, which is 25mm wide X 14mm tall.

FF35: Full Frame 35mm. Sensor dimensions equivalent to 8-perf horizontal 35mm film, which is 36mm wide X  24mm tall.

Blow-Up Ratio: Number of times an image is enlarged from its original, physical size in-camera, to its physical size on a display.

Dynamic Range: Number of F-stops of light a camera’s sensor can create usable images from pure black to pure white.

SSD: Solid State Drive. Storage that is a memory chip; not a spinning disk. SSD’s have huge advantages over conventional hard drives (HDDs) when the camera is moving, especially exaggerated movement, like car mounts.

Concurrent Multi-Format Capability: A camera’s ability to record more than one format simultaneously.

Transcoding: Changing a file’s format to either compress, de-compress, and/ or make it more edit-friendly.

Edit-Friendly Codecs: Editing highly-compressed files (like HD-SLRs) requires decompressing footage in real time, which puts a strain on the system’s processing power; the result can be unsmooth playback and slower render times. Transcoding to a more edit-friendly codec (like ProRes, in the case of FCP) relieves the issue—but adds another – needing more drive space. That’s where understanding the technical aspects and consequences of choosing a specific camera effects the workflow downstream.

Deliverables: The final format(s) for viewing by the intended audience.

Video Compression: Reducing the quantity of data used to represent digital video images.

Wavelet Compression: A type of compression that is visually lossless (like RED, Cineform and Jpeg 2000).

Block Compression: A type of compression that is visually lossy (like H264, AVCHD, HDCAM, DVCPro, mpeg-2, mpeg-4).

Video Artifacts: Degradation and distortion of an image’s resolution, contrast and color rendition, usually caused by compression.

Codec: A format’s compression scheme.

Color Space (chroma subsampling): Because of storage and transmission limitations, there’s a desire to compress video signals. Humans’ visual system is more sensitive to variations in brightness than color. So a video system can partially reduce color resolution with almost no visual difference as perceived by the viewer, like 4:2:2 – which requires two-thirds the bandwidth of 4:4:4. While 4:2:0 requires much less bandwidth, the visual difference is more noticeable, but considered an acceptable trade-off for the convenience it provides.

UHD Ultra-High-Definition -   New TV format and aspect ration announced in 2012 (also known as Ultra HD television, UltraHD, UHDTV, or UHD) includes 4K UHD (2160p) and 8K UHD (4320p)