How do I turn a hit point (a timecode I must land on) into a tempo and a click, and how close does the landing need to be?

Tempo times beats equals seconds: the editor (S3) and the Phaedrus Audio page (S12) both reduce hit placement to arithmetic, and S12 gives a worked click-book example in which 80 BPM misses a hit at 34 s by a quarter or half second but 81.13 BPM (17-6 frames per beat at 24 fps) lands it. S12 states a sync tolerance of two film frames (about 41 ms) with a rule of thumb of 0.1 s. A composer (S7) finds a rough tempo by tapping, then uses a software Find Tempo search over a tempo range. The arithmetic in S12 was re-checked by a batch-local script (consistent within rounding). Curator qualifications: Curator arithmetic: 60/81.13 x 24 = 17.75 frames per beat (click-book 17-6, i.e. 17 and 6/8 frames); 46 beats after beat 1 = 34.02 s, matching the source's '47th beat ... 34.03 seconds'; at 80 BPM, 34 s = 45.33 beats, a miss of about 0.25 s. Correction: the source states '≤2 film frames or ± 41mS', i.e. ±1 frame at 24 fps (a 2-frame window), not 'two frames (about 41 ms)'. The source also mislabels the click value as '17-6 frames/second' (it is frames per beat). Tolerance is ±41 ms (±1 frame at 24 fps; a 2-frame window), per the source wording. Note the source's 'frames/second' label means frames per beat. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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  "citations": [
    {
      "url": "https://simpsonsmusic500.wordpress.com/2011/08/09/music-editing-101-breakdown-notes/",
      "note": "hit/sync; click-book example"
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    {
      "url": "https://simpsonsmusic500.wordpress.com/2011/08/22/music-editing-101-the-scoring-session-2/",
      "note": "hit/sync; click-book example"
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    {
      "url": "https://www.phaedrus-audio.com/music_2_picture.htm",
      "note": "hit/sync; click-book example"
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    {
      "url": "https://www.artofcomposing.com/how-to-spot-a-film",
      "note": "hit/sync; click-book example"
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