I'm attempting to use a 2003-era external Apple iSight Camera with an M1 Mac mini via adapters:
iSight > FireWire 400 > FireWire 800 > Thunderbolt 2 > Thunderbolt 3
This same adapter chain works for video on a 2019 Intel MacBook Pro running macOS 10.15.6 Catalina. Audio required an additional fix, but is now also working on Intel.
On a new Apple Silicon M1 Mac mini, the video webcam does not seem to work. When first plugged in, it makes an autofocus sound and the green light turns on briefly.
Photo Booth is black and says:
There is no connected camera.
The FireWire Bus device is recognized by the M1 Mac's System Information:
Are there known FireWire support issues for either M1 Macs or macOS 11 Big Sur?
How can I use this iSight video webcam with my M1 Mac?
Apple Bug Report:
External iSight FireWire Camera does not work on Apple Silicon