Posted by Jan B on 04/16/06 16:57

(Sorry I had to work around a FreeAgent limit by move the follow up upwards in
the thread).

On Sat, 15 Apr 2006 09:45:05 -0400, Tom Stiller <tomstiller@comcast.net> wrote:

>In article <4440e4d2.109134196@news.individual.net>,
> nospam@nospam.se (Jan B) wrote:
>
>> When such a camera pans horisontally over a vertical object like a
>> pole and the video is displayed on a CRT that takes nearly a field
>> period to scan from top to bottom I would expect to perceive a tilted
>> object "moving" across the screen. This is since the scanning at the
>> bottom would lag the top when displaying but not at the recording.
>>
>> Have anybody noticed such effects?
>
>You overlooked the effect of the electronic shutter that effectively
>freezes the image before it is scanned out. There is no relative motion
>during the scanning process.

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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