Posted by ~P~ on 04/18/06 02:41

The CCD camera would take that one field and transmit it to the CRT and the
CRT would take 1/60th of a second to draw that field, exactly as it is
delivered to the display. If the CCD has caught it as one moment - in
1/5000th of a second (for example) then it would appear as a straight pole.
If the CCD has to scan each line and work from top to bottom and it takes
1/60th of a second, then you are correct in assuming that the pole would be
crooked. But, this would not be about the CRT putting it on the screen, it
would be about the original camera capture. Since cameras, as far as I have
ever seen, seem to work as a 'all at once' capture, you do not see a stair
stepping effect for a vertical line during panned shots. But, I am not as
familiar with CCD and different capture technologies that are used in video
production. Film, of course, is a total 'all at once' product.

"Jan B" <nospam@nospam.se> wrote in message
news:444276e6.212066235@wingate...
But that is excactly my point. The case cited above is the case with freezed
momentary picture in the CCD-camera, but the scanning in the CRT takes time.
To
get a smooth "momentary strobed" motion over the CRT surface, the camera
picture
should be scanned the same way (I think).

The "moving" vertical pole should have moved to a later position when the
CRT
scans the bottom lines.
/Jan

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