CHDK: unleash your Canon point-and-shoot camera

CHDK: Canon Hack Development Kit.
I was prompted to learn more about this thanks to lordhedgie via Silas, and it is truly amazing. CHDK is software which can be run on many Canon point-and-shoot cameras to give them vastly expanded photographic capabilities. The software is copied from your computer to a memory card (eg. SD card), which is then used in the camera to store photos as usual. It seems that the software doesn't alter the camera's firmware, but is simply run from the card to give the camera the new capabilities. The software can be set to be "bootable" by the camera, so that the software starts running when the camera is switched on (otherwise, it's a bit of a hassle to start the software each time). I have been trying this software on an A620 (2.5 years old), and the software is supposed to run on many A, S, G, and SD series cameras.

CHDK is open source and appears to be a large collaborative effort. I think there used to be a variety of software lineages, but now there is a main, unified "build" which is updated daily (not that it is necessary to update that often). In addition, there are individual scripts which can be run from within the CHDK software to add even more capabilities.

Here is the main page for the CHDK wiki, which lists the supported cameras:
CHDK wiki

The documentation for CHDK seems to be a bit fractured due to the software's evolution, but here's a good starting page:
CHDK manual ("firmware usage")

Downloads for the core CHDK software are consolidated on one page:
Download page

I have found the software a little tricky to learn. There are dozens and dozens of new menus and navigation is different than with the camera's own software. Now that I have figured out how to get around the menus, the location of important settings, and how to run a script, the camera can do a lot of new tricks (taken from the CHDK wiki):

• Live Histogram - CHDK includes a customizable, live histogram display, like those typically found on more expensive cameras.
• Zebra-Mode - Displays under and overexposure areas live on the screen.
• RAW - CHDK can record raw files, giving you access to every bit of data the sensor saw, without compression or processing. Raw files can be manipulated on the camera, or processed on your PC. CHDK also has experimental support for the open DNG raw standard.
• Override Camera parameters - Exposures from 64s to 1/60,000 sec with flash sync. Full manual or priority control over exposure, aperture, ISO and focus.
• Bracketing - Bracketing is supported for exposure, aperture, ISO, and even focus.
• Video Overrides - Control the quality or bitrate of video, or change it on the fly.
• Scripting - Control CHDK and camera features using ubasic and LUA scripts. Enables time lapse, motion detection, advanced bracketing, and much more. Many user-written scripts are available on the forum and wiki.
• Customizable OSD - Improved display of battery status, free space, camera parameters, and much more.
• Fully customizable with an on-screen editor.
• USB remote - Simple DIY remote allows you to control your camera remotely.
• User Menu - Edit your own customizable User-Menu for fast access to often used features.

My experience with the software is that it generally works very well. It has seemed to "crash" a few times, always during menu hopping, but the camera just had to be cycled off and on, at worst. The live histogram, zebra-mode and battery % display are very useful. Saving RAW or DNG files works. I've gotten some scripts to work, such as various bracketings, time lapse, and motion detection.

I've always wanted to be able to do time lapse photography, and have been trying it out on my "new" camera. Yesterday had some good clouds and movement as viewed from my house, so I ran a time lapse (intervalometer) script that is straightforward and works well (titled "Accurate Intervalometer"). The longest sequence is 1500 photos at 6 second intervals, total of 2.5 hours. The movie from the photo sequence was made at 30 photos/second, so that's time compression of 180x (true for all of these). These are mp4 movies - might not work if you don't have Quicktime - and the largest file is ~12 MB.

Clouds 1: 2.5 hours compressed into 50 seconds (a bit overexposed)

Clouds 2: short but spectacular (the clouds disappeared too soon)

Clouds 3: sunset (and a crow appears on tree top for about 3 minutes)

If you are interested in turning your Canon point-and-shoot into a much more sophisticated camera, it's definitely worth investing the time to learn how to used this CHDK software.

That is awesome! Great timelapse too; those clouds look amazing. Too bad I have a Sony...

Whoa, cool stuff, may have to find an old A-series on CL to play with.

Here's another time lapse movie taken using the same script ("Accurate Intervalometer") as the cloud movies. File size is around 16 MB, mp4 format, time compression 450x. This movie could be titled "How to Make a Snowman Out of Slush, Grass, and Leaves", or alternatively:

The Rise and Fall of a Snowperson

If anyone is interested in this software (core CHDK plus 8 scripts that I have gotten to work) for their Canon point and shoot, I'd be happy to zip it and make available for download.

pretty cool Charles!

I've looked at the CHDK offerings before....but never tried any. I have a Pro 1 and EOS 1D Mkll.....but had an A 710, which I replaced with the 12mp A650 when it was swiped.   It's the only one that doesn't have raw...but, as I've seen, there's a lot more that can be done than just allow these cam's to capture images in Raw.

Absolutely, there's more than RAW... There's also Othello. There's nothing better than having someone gape as you play games on your camera.

Seriously, there are loads of neat features, and I never could find a disadvantage to using CHDK.