DIY USB Knob Box Replaces Blackmagic Design Camera Remote
Glen Akins' USB Knob Box features a PIC18F45K50 microcontroller, a pair of encoders, and several buttons for different functions.
In what looks to be a throw-back remote for a late 50’s TV, engineer Glen Akins’ USB Knob Box doubles as a Blackmagic Micro Studio Camera remote with a 16mm 4K sensor he uses as a webcam. The only issue he had with the makeshift webcam was with the focus and exposure controls were automatic, which are fine when using ATEM video switchers, but a pain when using the camera without it.
To get around that issue, Akins built the USB Knob Box that allows him to control the exposure without using the focus ring and buttons on the front of the camera itself.
One of the great features of the Blackmagic Design Micro Studio Camera is it can be remotely operated, which can be done in several ways, including via an HD-SDI return video feed, LANC port, or through the S.BUS port. While the first two connection methods have their merits, Akins decided to go with the S.BUS port to control the camera with his USB Knob Box, enabling him to map camera and lens control data into servo channels.
Akins' USB Knob Box is based on a Microchip PIC18F45K50 microcontroller and features ALPS EC11 series encoders that adjust white balance, gain, shutter speed, and the camera iris. Another encoder is tasked with focus fine adjustments, making it easy to dial in 4K images. He added a pair of buttons with LED illumination, which allows the USB Knob Box to enter USB bootloader mode during powerup and switch between using the big knob to adjust lens focus and using the big knob to adjust zoom.
Akins has uploaded a detailed walkthrough of his USB Knob Box, complete with schematics, for those who would like to recreate his project.
