Capture
The capture process fixes the "natural" frame rate of the image sequence. Moving image sequence can be captured at the rate which is different from presentation rate, however this is usually only done for the sake of artistic effect, or for studying fast-pace or slow processes. In order to faithfully reproduce familiar movements of persons, animals, or natural processes, and to faithfully reproduce accompanying sound, the capture rate must be equal to, or at least very close to the presentation rate.
All modern moving image capture systems use some sort of a mechanical and/or electronic shutter. Shutter allows the image for a single frame to be integrated over a shorter period of time than the image change period. Another important function of the shutter in raster-based systems is to make sure that the part of frame scanned first (e.g. the topmost part) contains image of the scene integrated over exactly the same period of time as the part of frame scanned last.
Early TV cameras (see Video camera tube) did not have a shutter. Not using shutter in raster systems may alter the shape of the moving objects on the screen. On the other hand, the video from such a camera looks shockingly "live" when displayed on a CRT display in its native format. See, for instance, the black and white PAL TV recordings of early Beatles performances.
Read more about this topic: Moving Image Formats
Famous quotes containing the word capture:
“Because the young child feels with such intensity, he experiences sorrows that seem inconsolable and losses that feel unbearable. A precious toy gets broken or a good-bye cannot be endured. When this happens, words like “sad” or “disappointed” seem a travesty because they cannot possibly capture the enormity of the child’s loss. He needs a loving adult presence to support him in his pain but he does not want to be talked out of it.”
—Alicia F. Lieberman (20th century)
“This is the hope of many adolescent girls—to capture a parent’s heart with love for them as they are, as people. They reject the notion of being loved just because they are the child of the parent. They want the parent to fall in love with them all over again, because being new, they deserve a new love.”
—Terri Apter (20th century)
“This is no rune nor symbol,
what I mean is it is so simple
yet no trick of the pen or brush
could capture that impression;
what I wanted to indicate was
a new phase, a new distinction of colour.”
—Hilda Doolittle (1886–1961)