JVC GR-DLS1 manual Description of Progressive Scan CCD, Frame

32ENRECORDING

AdvancedFeatures(Cont.)

Description of Progressive Scan CCD

Progressive Scan is a special image sensing method which, unlike conventional interlace scanning, is able to pick up all the lines of picture information in one Scan. Since the Progressive Scan CCD is capable of outputting 60 full Frames* per second — twice the amount of conventional systems — it is able to deliver a high quality picture even when its output signal is converted to a format that can be viewed on a TV screen.

*A NTSC TV screen image is composed of 30 Frames per second. 1 Frame is made up of 2 Fields.

1. Regular shooting of moving images

1 Frame

Scan A Scan B

Records 30 odd and 30 even image Fields, for a total of 60 per second. Since there is a time lag between an odd and even Field, when they are combined to make 1 Frame the part of the image that is moving appears as image jitter. However, during normal playback, the moving picture looks smooth and natural.

Odd-number Field Even-number Field

2.Progressive mode shooting of moving images (Progressive Video Recording ☞ pg. 46)

Scan A Scan B Scan C

Skip

Scan D

Skip

Odd-number Even-number		Odd-number Even-number
Field	Field	Field	Field	30 Frames per second

Scan A is recorded, divided into an odd- and even-number Field, and then Scan B is skipped. Scans C and D are handled in the same way as Scans A and B, as illustrated above, thereby recording 30 Frames per second.

Since each recorded odd- and even-number Field originates from the same Scan there is no time lag between them, and so when they are combined into a Frame and a still image is displayed on a TV or PC monitor the picture does not look jittery. However, when moving images are played back, the picture can look unnatural.

3. Pro Snapshot recording (☞ pg. 30)

When the Progressive button is pressed, the current frame will be recorded for about 6 seconds in the Progressive mode (except when Multiple picture mode and Color bar mode are being used).