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-   -   Have you tried souping up your Canon with CHDK (

bill2468 Aug 31, 2008 11:38 PM

On you tube there are several videos on upgrading your Canon via CHDK that puts program info on a memory chip without altering the formating of camera (I would think that images go to internal memory or on sqme large chip that holds CHDK stuff.


LimeyKev Oct 3, 2008 11:50 AM

Yes - I have done this with my SX100IS. Can now shoot in RAW (not that I do) and can optically zoom when shooting video. Battery indicator is now a percentage which is VERY useful. Lots of other things which I haven't gooten around to look at yet.

kidtree May 25, 2011 6:37 PM

I've played with CHDK a little, and I like it. It has kind of a steep learning curve, just because it adds so many functions and options to your camera, but if you're a Steve's reader, you probably love exploring menus, anyway. Some of the advanced functions offered by CHDK are duplications of things I already had in my Powershot S3IS: bracketing, ability to zoom while shooting video, etc., but others are new to me.
Here's a simple comparison of shutter speed range, for example:
S3IS, normal: 15 seconds to 1/2000
with CHDK: 2048 seconds to 1/100,000
Then there's the additional viewfinder info, like percent of battery remaining, and exact zoom level (in absolute terms, or 35mm equivalent).
These capabilities are built into the camera's processor, but Canon chose not to make them available to us and confuse our little heads. The hackers who built CHDK just bring them to the surface for our use.
RAW shooting is another example. No camera shoots JPEGs. They shoot some kind of RAW format, then convert it to JPG before storing it to your card. CHDK gives you the option of intercepting the RAW pic and storing it, just like the big guys with their SLRs.
I haven't used scripts yet, but they extend the cameras even further. Write your own script if you want, in either of 2 languages, but there is a library of stock scripts for the most desired functions. Rig a battery and switch with your USB cable, run a script, and the camera will trigger when you press the switch - you now have a cable release. Run another script, and the camera will quietly wait until it detects movement in a pre-determined area of the viewfinder, then trigger. A branch of CHDK, called SDM (Stereo Data Maker), is tailored to making stereo shots with two cameras on a common cable release.
CHDK takes up only a small amount of you memory card, and you can erase it any time. You can turn CHDK on and off with the tiny LOCK switch that's built into the edge of the card, or activate it from the menus. It doesn't change your numbering sequence; you can switch back and forth between CHDK and normal Canon brains, and the shot numbers will count up normally.
I've barely played with CHDK, but I've shot a little bit of RAW with a camera that can't shoot RAW, and I've shot a 34-minute star-trails pic with a camera that can't stay open longer than 15 seconds, according to its manufacturer.
Read the installation instructions carefully and go for it.

Ozzie_Traveller May 25, 2011 6:48 PM

G'day all

first reaction ... goodness gracious - what a wonderful bit of "hacking" for the benefit of the user community

Regards, Phil

kidtree May 25, 2011 6:57 PM

Here's a caveat for CHDK users who want to take long exposures. A big problem with shooting in the dark is noise spontaneously generated in the image sensor - the speckles that show when you set the ISO too high, or the shutter is open too long. CHDK can automatically compensate for the noise, but you need to be mentally prepared for it, or you may think your camera is broken. It does so by automatically taking a second "dark" shot, then subtracting any speckles in that black shot from your original photo. That's a fine idea, but it meant that after my 2048-second (34-minute) exposure of star trails, my viewfinder went black for an additional 34 minutes. That's scary if you don't know what's going on. It also requires fresh batteries to keep your camera going for over an hour for one shot.
The second shot is only taken after exposures of 1 second or longer, I believe, and it will be as long as your original shot.

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