4 HN users recommended this explainer4 months2016–2025score 4.5
Years with an HN recommendation, 2007–2026
Go-to explanation whenever the strange 29.97 frame rate comes up, praised for its clarity and presenter.
Matt Parker explains the history behind NTSC television running at 29.97 frames per second rather than 30, tracing it to the backward-compatible addition of color. He walks through the arithmetic behind the odd ratio.
“definitely go and watch Matt Parker's legendary explanation of why NTSC runs at 29.97fps” (HN, 2020)
If anyone wonders where the odd NTSC frame-rate ratio originated from, Matt Parker (standupmaths) did a comprehensive video, with some original write-up on this recently: [this video]
Matt Parker's comprehensive explanation of the NTSC frame-rate ratio.
For anyone this deep on the thread, check out this video (great presenter!) explaining TV spectrum allocation, NTSC, PAL, and the origin of 29.97 fps. [this video]
TV spectrum allocation, NTSC, PAL and origin of 29.97 fps.
That comes from the old NTSC standard and the history of adding colour in a backwards compatible way: [this video] In the case that the above posters are mentioning, this probably has less to do with NTSC compatibility and more to do with bad timing hardware or cameras that attempt to do too much in PIO mode instead of using real encoding hardware.
Explains NTSC color backward compatibility and the odd frame rate.
Video list and Hacker News comment labels from HackerTube (prompted by @karpathy), released under ODC-By 1.0, built on the open-index/hacker-news archive. Hacker News data is provided by Y Combinator; comments remain the work of their authors. Video titles, channel names and thumbnails belong to their creators and are shown via YouTube. HackerTube Watch is an unofficial edition. Data export of 2026-10-31.
Plays via YouTube's privacy-enhanced embed
5 Hacker News comments
From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.
Citations, criticism and jokes