Canon EOS R6 Advanced User Guide - Page 293

Cards That Can Record Movies See Card performance requirements for details on cards that can record at each level of movie recording quality. Test cards by recording a few movies to make sure they can record correctly at your specified size ( ). Caution Before recording 4K movies, format cards by selecting [Low level format] in [ : Format card] ( ). If you use a slow-writing card when recording movies, the movie may not be recorded properly. Also, if you play back a movie on a card with a slow reading speed, the movie may not be played back properly. When recording movies, use high-performance cards with a writing speed sufficiently higher than the bit rate. When movies cannot be recorded properly, format the card and try again. If formatting the card does not resolve the problem, refer to the card manufacturer's website, etc. Note To obtain better performance with the card, formatting the card with the camera before recording movies is recommended ( ). To check the card's writing/reading speed, refer to the card manufacturer's website, etc. 293