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"And so, looked at in terms of half-fields of video, the transfer will look like this: 1, 2, 3, 4, [5], 6, 7, 8, 9, [10], etc, where the numbers in brackets represent the half-fields missed during the film pulldown. "
This is correct. the first 24-per-second frame of film is identical to the first 30-per-second frame of video (half frames 1,2,3,4), but the second 24-per-second frame of film has its bottom half first field coming from half frame 6. then the top and bottom from half frames 7 and 8 respectively, and then the top from half frame 9, which is beginning a third video frame. So, there is a motion discontinuity half way down the film frame on every other film frame. The CRT has to be blanked exactly halfway down the frame and the film position has to be very constant during the four half frames of exposure. On some kinescope recordings you can see that this did not happen exactly, as there is a horizontal line flickering between lighter and darker halfway down the screen.
Now,as to flicker: if the film camera used 30 frames per second and fast pulldown, you would get a perfectly fine 30 frame per second film without any of the half-frame mismatch. However, two fields that should be separated in time would be combined in one frame. When this is scanned by an interlaced camera, you get a motion *judder* that is similar to double-shuttering a thirty frame per second film. Maybe that is what the author really meant. I do not see how flicker is any different from the regular 60 field per second video, because the TV picture tube is being scanned interlaced as usual. So, maybe the author confused judder and flicker. Does he use the term "judder" anywhere? There is "3:2 pulldown" judder when televising 24 frame per second film on a 60 field per second TV system. The 24 frame-per-second kinescope recordings, when re-televised as 60 field per second video, have even more complex judder due to the half-field offset of every other film frame.
Bottom line, I think the sentence in question is not correct, and the most gracious interpretation is that the author was thinking of judder but was sloppy in his terminology. If I were his editor, I would have said "What did you mean? This doesn't make sense to me."
"It is just not clear to me how the process I have outlined above, which involves losing some part of the image, retains interlace..."
It retains interlace because in the second film frame the last top half field (9) is the opposite parity of the first top half field (7).
Film frame 1:
1 top odd
2 bottom odd
3 top even
4 bottom even
[skip 5 top odd]
Film frame 2:
6 bottom odd
7 top even
8 bottom even
9 top odd
[skip 10 bottom odd]
and so on
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