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Hacking Canon Point-and-Shoot Cameras
Pig Hogger writes "If you're stuck with a cheap Canon point-and-shoot camera and have feature envy over the neighbor's sophisticated latest model, fret not! According to this LifeHacker article, the CHDK project allows nearly complete programmatic control of cheap Canon point-and-shoot cameras, enabling users to add features, up to and including games and BASIC scripting."
It's for more than that of course. It allows you to enable certain camera functions that do not exist in the shipping firmware, like RAW mode.
Um, changing the firmware isn't going to put a LCD screen on the mirror. Apparently you haven't grasped how a SLR works.
The firmware probably isn't going to be able to get the shutter to go any faster reliably. What you need to use is a ND filter if you like wide apertures.
Certainly the scripting stuff could be used in a SLR.
If I have nothing to hide, don't search me
There is no risk of "screwing up" your camera, the hack loads the "firmware" into volatile ram in such a way that simply deleting the file from your mem card will revert your camera to the original state.
-*The above statement is printed entirely on recycled electrons*-
Wired.com also mentioned this stuff recently. I tried it - awesome.
One of the coolest features is that at any time you can restore your camera to default settings just by turning it off - no permanent flashing of BIOS/firmware!
Actually, don't the shutter blades always fall at the same speed? Their speed is the flash sync, the fastest speed where the whole film is exposed at a single point in time, right?
Then to set the 'shutter speed', the time between the first shutter blade and the second shutter blade is changed.
At least, that is how Focal Plane shutters work. Leaf shutters are different.
If I have nothing to hide, don't search me
What exactly was hard about the instructions?
When I first found out about CHDK I had it running on my camera *3 minutes* after the download completed.
All you do is:
1) copy the files to your flash card
2) Power up the camera in playback mode while holding the menu button to add the firmware update option to the menu. This is something you should already know how to do from the cameras manual!
3) Select the update.
Once the files are on the flash card you can repeat this process at any time in under 15 seconds. If you want to use the stock firmware then you just don't run the update.
The custom firmware has all kinds of neat features. If you like making HDR pics, you can use available scripts or write your own to bracket the exposures. My Powershot A620 now has the ability to shoot RAW thanks to CHDK.
Some builds even incorporate face detection and motion detection. Screw webcams, how about having a 7 megapixel camera capturing what's happening outside your window.
Time lapse photography is now a cinch, as are all kinds of things that the stock camera doesn't do.
I never found any of the features to be all that hackerish. They don't document using a histogram, sure... but if you're downloading a firmware for the use of a histogram, you probably already know what one is!
The risk of screwing up your camera comes from potentially feeding it a parameter outside of it's safety zone.
For instance what if there were a RAM mode in the hacked firmware for firing the flash at a rate faster than the camera's default firmware would allow. You try it for that super cool skateboard picture and wonder why your flash Fresnel is brown and smoking after the fact. Granted the caps shouldn't be able to do that, but what if?
Or you try to drive the aperture 1 click past its physical limit? Do you know if the camera has limit switches or is relying on firmware pointing to known values in RAM (pulled from EEPROM at boot) that define the scope of aperture values to control that motor? Maybe it can handle a few slams at the end of travel, but what if you keep doing it by mistake?
Or you use a mode to leave the LCD backlight on while the flash caps recharge (normally the LCD backlight is off) and you fry the power supply in the camera because you sourced too much current?
Or you use a mode to drive the lens into the extended position, but somehow the hacked firmware ignores the limit switch for the little lens cover door and tries to run it at the same time? Scraaaaape.....
Don't get me wrong, this looks freakin' cool! But to presume there is zero possibility of damage seem naive to me.
I'm thinking about it, therefore I might be.
Although, for RAW images, cheap point and shoot cameras don't have physical build, and lack everything that makes RAW images special. Taking RAW images with my camera was akin to storing 1 MB JPEG image into 3 MB RAW format.
RAW images should give you the ability to white-balance them after the shot. (You at least can with the RAW images from my DSLR.)
That alone is worth the price of admission (i.e. a larger memory card) IMHO.
They are already doing that, e.g. encrypting the firmware in the 350D model.
http://forums.dpreview.com/forums/read.asp?forum=1010&message=23803446
factor 966971: 966971
Nope. It runs VxWorks, at least that is what the firmware dump from my Canon indicates.
Time makes more converts than reason
Because it's physically impossible on an SLR. In an SLR, you have the lens, that then is followed by a mirror. The mirror, in the "down" position, reflects the light from the lens through the prism viewfinder and then to your eye.
When you click the shutter, the mirror flips up (viewfinder goes dark), exposing the shutter which then opens and shuts the right amount of time the actual camera sensor.
That's not to say it's not possible to say, add a little cameraphone like sensor and offer a live preview (several dSLRs do this now), but historically, it wasn't possible. The light is either going to the main camera sensor, or the viewfinder. A small amount is actually reflected *down* for autofocus, though.
Though, as anyone knows, holding your camera at arm's length (so you can use the LCD as a viewfinder) sucks for camera shake. And most camera LCDs are of QVGA or lower resolution, so you miss out on all the nice little details youc an see through a real optical viewfinder like that on a dSLR...
No, they renamed the original G to GL, jacked the price up $20, then came out with a new, shitty router that they named G for the same price that the better hardware had been before. And all this while hardware costs should have been going down anyway (as is the general trend in technology).
(Have you got a hint abut why people are pissed off yet?)
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
RAW gives you more image information, as you haven't gone through a lossy RAW->JPEG conversion. Whether this is to correct an under/over-exposed picture (or both*), or to compensate for an incorrect (or impossible**) white balance setting.
You're right, a bigger sensor and lens will give you a better picture. But for a given maximum camera size, RAW will give you the potential*** for better images than JPEG. Perfect for an undercover paparazzo who needs to blow up that discreet underexposed celebrity shot to sell to US Magazine.
A decent analogy is that with JPEG you've thrown away the 'negative', and are left with only a print of the image, throwing away the rest of the information contained in the negative. If you really care about the image, or are going to spend hours working with it in photoshop, wouldn't you rather be working with an image taken from the negative, rather than the print?
* example of an under- and over- exposed picture: a person wearing a hat on a sunny day. The outside of the cap can be overexposed, while their face is underexposed. As RAW stores the image with a higher colour bit depth, you've got a chance of recovering the over and under exposed area.
** example of 'impossible' white balance: a room lit by candlelight, which has a window with an overcast sky outside. Either the room will look orange, or the window will look blue, or both- there's no way to make both areas of the picture look correct with one white balance setting. Changing the white balance of one area of the JPEG that radically will throw away masses of information, and look terrible. With RAW, you can render the picture twice with two different white balance values, one for the overcast sky, and one for the candle, and merge the two images together.
*** With a perfectly exposed picture that has the correct colour depth, the only real advantage of RAW is that you avoid the JPEG compression, but with these small sensors you're probably only going to see noise there instead of the compression, so it won't make a lot of difference.
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A good firmware won't help you in any way if you are limited by the specs of your camera. You should go for the best combination of a good (i.e. not too small) CCD and the zoom coverage you need. The G7 and the SD870/ Ixus860 would be some good picks.
...."Have you mooed today?"...
When you upgrade firmware in a Canon camera, there is scope to run an application before the firmware upgrade. What CHDK does is trigger the upgrade process, but doesn't upgrade the firmware -- it just uses the firmware upgrade routine to run the CHDK code on top of the firmware. The camera still works, and the CHDK code has access to all the camera variables, allowing you to do pretty much anything you want. But the underlying firmware remains unchanged (and thus your warranty isn't void).
It's all rather neat, and the CHDK code is easy to hack around with (I've done so in the past).
You don't understand what RAW is for, do you? Actually, he/she does. I use CHDK, and I can tell you that there's very little extra info in those 10-bit raw files (that's all you get from the Canon P&S line). Remember that a lot of that extra room already goes in whitebalance correction.
You *can* get a bit more non-colour information out of the highlights if you really push it, but really
That said, it's still nice to have the capability, but in the real world it's just not that useful most of the time. What *is* really nice about CHDK are the live histogram capabilities -- the live merged RGB histo is outstanding in getting the exposure right (and I don't know of any other P&S camera that provides this capability).
RAW gives you the full bits per pixel available. This can be up to 14 in the recent DSLRs. Let's assume a P&S can give you 10 bits/pixel.
That's two more stops than a standard 8-bit JPEG, even at "maximum quality".
JPEG compression artifacts aren't the real problem - it's the colour depth available in RAW.
So shooting RAW allows you to rescue the highlights and shadows. JPEG compression artifacts are a red herring.
Of course, if we used PNG or 16-bit capable JPEG (with full EXIF), then there wouldn't really be this problem...
http://blog.grcm.net/