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Re: Keycode number fields

PWACKER wrote:
> I have received my first telecine with Keycode windows and I am
> unclear as to what is the precise information conveyed in the last
> alpha-numeric field of the Keycode number.  I know that it is related
> to postion in the pull-down sequence, but I was a bit confused when
> reading the sequence frame to frame on the video.  Each five video
> frame sequence of Keycode numbers ends A1  B1  B3  C2  D2, with each
> value appearing to be the same for both fields of a specific video
> frame.

Sounds like you're looking at this on a VHS tape, which will only show
field stills, in your case, video field 1. So what you're actually
seeing is the first field of the "A" frame (TC frame 1, field 1), which
is a 2 field scan. The next field is the first field of the "B" frame
(TC frame 2, field 1), which is a 3 field scan. The next field is the
third field of this scan (TC frame 3, field 1). The next one is the
second field of the "C" frame, which is a 2 field scan that begins on a
field 2 (TC frame 4, field 1), thus the first field of this frame is on
the previous field 2, which you cannot see. The last field is the 2nd
field of the "D" frame, a 3 field scan that also begins on field 2 (TC
frame 5, field 1). Once you get past the 5 frames, the sequence starts
again with a new "A" frame. 

Hope this isn't ridiculously confusing.

Mike Most