Pre roll or cache record allows for a short recording time to be captured continuously prior to pressing the record button (approximately 8 seconds in HD and 2-3 seconds in 4K being cached into memory). This option is enabled from the input menu under Record section and is available on the Shogun/Ninja Assassin/Flame and Inferno series. To flag that pre roll is activated, you will see a white circular arrow around the record button and a red Pre Roll icon will flash in the top left hand corner. The frame rate and codec selected will affect the number of seconds being cached for pre roll. Using a lower bit rate codec setting and shooting at lower frame rate will increase the length of pre-roll. When the record button is pressed or trigger is sent, the buffered pre-roll data in memory will be written out to the start of the recording. This means if you are few seconds slow hitting the record button when something interesting happens you will still capture the shot.