“On the video clips I capture there is a small 1 or 2 pixel line drop,
halfway along the top edge of the image.
Okay … this is going so far back into my memory banks that my knees are shaking,
but I believe that the first and last lines of a video images actual start & finish respectively, half way across the screen.
That’s what you are seeing there …
I suspect that it has to do with the image being 16:9 anamorphic, capturing off PAL a Digibeta deck, a type of over-scan perhaps?
… follows on from what I said.
I have seen similar thing with DV CAM 16:9 anamorphic but the difference is that there is a thin white dotted line along the top left edge of the frame.”
… also follows on from what I said, however you are almost certainly describing a line of data (vertical interval timecode – VITC) which exists in the video signal before(read ‘above’) the visible area of the video signal.
Occasionally, that part of the signal which is not part of the visible signal, drops down into the visible area and so, logically, we see it.
That’s what you are seeing. Probably only 1 lines worth.
Happens a lot with anamorphic material in FCP.
Neil.