# Fractional frames per second in advanced digital cameras?

**URL:** <https://boards.straightdope.com/t/fractional-frames-per-second-in-advanced-digital-cameras/1015051>\
**Category:** Factual Questions\
**Created:** [March 3, 2025, 3:19am UTC](https://boards.straightdope.com/t/fractional-frames-per-second-in-advanced-digital-cameras/1015051 "2025-03-03T03:19:03Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\
**Post date:** [March 3, 2025, 3:19am UTC](https://boards.straightdope.com/t/fractional-frames-per-second-in-advanced-digital-cameras/1015051/1 "2025-03-03T03:19:03Z")

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I was reading about the Thomson Viper FilmStream Camera, an advanced (for the time) digital camera. It can operated at numerous fps rates. But some of them are not even fps and are slightly off. For instance the camera can operate at 24 fps but also 23.98. It can also operate at 29.97 and 59.94 but does not offer 30 or 60 fps rates. What do these odd rates achieve?

> **[Thomson Viper FilmStream Camera](https://en.wikipedia.org/wiki/Thomson_Viper_FilmStream_Camera)**
>
> The Thomson Viper FilmStream Camera is a digital movie camera produced by Thomson Multimedia (now Vantiva). Introduced in the early 2000s as makers of feature films were turning to digital cinematography, the Viper influenced subsequent HD, UHD, and HDR cameras.
> The Viper FilmStream was announced in 2002 by Thomson after being developed by its Grass Valley subsidiary which it had purchased earlier that year. It followed early Sony CineAlta cameras and preceded the Panavision Genesis by less than...

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**Author:** ![N9IWP](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/n9iwp/32/3154_2.png) [@N9IWP](https://boards.straightdope.com/u/N9IWP)\
**Post date:** [March 3, 2025, 3:29am UTC](https://boards.straightdope.com/t/fractional-frames-per-second-in-advanced-digital-cameras/1015051/2 "2025-03-03T03:29:55Z")

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29.97 is what NTSC used. Apparently changed when color was added.

> **[NTSC | Color encoding](https://en.wikipedia.org/wiki/NTSC#Color_encoding)**
>
> NTSC uses a luminance-chrominance encoding system, incorporating concepts invented in 1938 by Georges Valensi. Using a separate luminance signal maintained backward compatibility with black-and-white television sets in use at the time; only color sets would recognize the chroma signal, which was essentially ignored by black and white sets.
> The red, green, and blue primary color signals 
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Brian

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**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\
**Post date:** [March 3, 2025, 5:18am UTC](https://boards.straightdope.com/t/fractional-frames-per-second-in-advanced-digital-cameras/1015051/3 "2025-03-03T05:18:23Z")

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A long explanation here:

> **[29.97 Things You Didn't Know About Frame Rates](https://www.studionetworksolutions.com/video-frame-rate-facts-and-figures/)**
>
> Understanding your footage is an important part of being a video editor. Learn the history and standards of the video frame rate.