420D is an unofficial fork of the 400plus firmware add-on, originally developed for the Canon EOS 400D (also known as the Digital Rebel XTi). This version targets the 20th anniversary of the 400D by building upon the original project with updates, improvements, and a refreshed focus.
- Modernize and clean up the original codebase
- Improve documentation and accessibility
- Modify existing features to personal taste
- Add new features suited to today’s use cases
- Extend the useful life of the Canon EOS 400D
This project is based on the original 400plus/400plus repository. Full credit and thanks go to the original developers for their outstanding work.
The original source code is licensed under the GNU GPL v2, which this project continues to honor.
Some of the most popular features of 400plus are:
- Custom modes:
- Complete snapshots of all settings and parameters.
- Can be assigned to any scene mode for a quick access.
- Store up to 16 custom modes on each CF card.
- Scripting support:
- Extended AEB,
- Flash, Aperture, Exposure, and ISO based AEB,
- Ultra-long exposures, featuring a long-exposure calculator,
- Intervalometer, featuring a time-lapse calculator,
- Bulb-ramping,
- Self-timer,
- Touch-less trigger,
- Depth of field and hyperfocal calculator.
- Extended range for some parameters, line Av or Flash compensation.
- Custom white balance, up to 16 color temperatures can be named and stored.
- View and change the ISO while looking through the viewfinder.
- Our own configurable AutoISO.
- Safety Shift for creative modes.
- Extended AF patterns.
- Intermediate ISO values.
- Spot metering mode.
- Multi-spot metering.
- Fixed exposure for M mode.
- Quick exposure button for M mode.
- Configurable buttons.
- RAW file format output for auto modes.
- Release counter.
400plus has been translated into several languages, and can even be translated to languages not supported by the camera.
- Revamped user interface
- Menu reorganization
- Few modifications/corrections according to 400plus issue tracker
To build the project in a clean and reproducible environment, you need to install podman, then:
- make
will build the docker image if necessary, then build the software in the container.
- make install
will copy the generated software and files to the INSTALL_PATH, defaulting to ./output
- make clean
will delete the intermediate build files (but not the docker image).
Please, read "a word of warning" at our wiki before doing anything else.
There is a user guide, where you can get a better idea of what to expect from this project. Then, if you want to give it a try, there is also an installation guide.
Installation instructions will be added once testing is complete.
This project is released under the GNU GPL v2 license, in accordance with the original 400plus project. See LICENSE for full terms.
- Project started in 2025 by Frederic Cordonier
- A tribute to the Canon EOS 400D – August 2006–2025 ❤️