Arducam High-Resolution Autofocus Camera (16MP IMX519) for Raspberry Pi Bullseye and Buster OS have the problem where the pre-installed libcamera is unable to open the Arducam 16MP IMX519 camera modul..
With the new release of Bullseye (Debian version) Raspberry Pi OS based (8th November 2021), there are many enhancements and improvements. the older commands like raspistill will NOT work anymore...