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• Manual Focus Controls Logitech C920 Onboard
• Manual Focus Controls Logitech C920 Online
• Logitech C920 Software

There are many UVC compatible webcams most of them support full auto mode but only a few of these cameras provide extended manual white balance, gain and exposure control. Kurokesu C1 family (C1, C1 PRO, C1 MICRO), Logitech C920 and Brio are the ones that can be trusted.

Logitech® HD Pro Webcam C920 Features 1. Carl Zeiss® autofocus HD 1080p lens 2. Activity light 4. Flexible clip/base 5. Tripod attachment 6. Product documentation c920 Getting started with Logitech® HD Pro Webcam C920 5 6 1 4 3 2. Logitech® HD Pro Webcam C920 Features 1. Carl Zeiss® autofocus HD 1080p lens 2. Activity light 4. Flexible clip/base 5. Tripod attachment 6. Product documentation Setup Guide Logitech® HD Pro Webcam C920 5 6 1 4 3 2.

There are few tools to work with USB cameras in Linux. Probably V4L2-CTL is the most advanced and recommended command line tool for advanced users.

Fresh Linux might be missing utility, install it with simple command:

Now let’s see what we have connected on USB port

Note two interfaces for Kurokesu C1 camera – this is dual stream output. One video device is for regular YUYV/MJPEG compressed output another is for h.264. You can open both of them at the same time with different programs (for example h.264 for live streaming, MJPG for onboard recording or computer vision processing)

List available controls

Video for Linux V4L2 can report all available controls to single list. List is self explanatory with possible value ranges.

Kurokesu C1 family

Logitech C920

Logitech Brio 4K

Reading current value

Read current UVC value with command below. Actual value is reported back below.

Setting new value

In order to set new camera parameter value use command syntax like this:

In some cases it is necessary to switch parameters in certain order for parameter to be set. For example change manual white balance control before setting fixed value:

Kurokesu C1 extension unit and firmware customization

Besides standard UVC control it is possible to customize Kurokesu C1 family camera firmware to meet specific customer needs, for example:

Manual Focus Controls Logitech C920 Onboard

• Set default UVC control values
• Edit de-noise parameters
• Edit USB frame size
• Edit MJPEG compression rate
• Edit h.264 bitrate
• Set low light behavior (lower down to 2 frames per second automatically or maintain stable frame rate)
• and much more

Manual Focus Controls Logitech C920 Online

Camera Extension Unit is designed for Linux and allows to alter even more controls not covered by UVC protocol (for example: spot/center/frame measuring mode).

Logitech C920 Software