I have been playing around with CHDK successfully installed on my guinea-pig camera, an SD880; well...., not really installed on the camera, but installed on the SD-card.
Entirely due to the magnificent results that we have been getting with DxO Optics Pro 9 Elite (with Prime), my main reason for this venture was so I could capture RAW image files.
While it is now entirely possible for me to capture three flavors of RAW files -- plain straight-off-the-sensor CHDK RAW files, and two versions of DNG - 1.1 and 1.3 -- , there are a few unexpected shall I say "cons" that I have had to address (or hurdles to clear or summits to peak)
Any memory-card larger than 4GB must have two partitions, a 16MB "Boot" partition and a FAT32 everything else partition.
Due to a shortcoming in anything Windows prior to the most recent version of W-10, Windows will not acknowledge anything on a removable flash storage device except for a single "Primary" partition, in this case it being the 16MB boot partition.
I poked my card in the reader; and, no matter what trick I tried, all I could see was the contents of the boot partition.
I could have used Disk Management and removed the Drive letter from the boot partition to the images partition and made the images partition the Active Primary partition and then be able to access my pictures; but then, once I got done with the pictures, I would have had to reverse the procedure before putting the card back in the camera; and, I would have to have done this every time I wanted to access the card.
What I ended up doing is get a free "portable" program called WASP; of course, I had to also install dreaded JAVA for WASP to work (I had to have JAVA for STICK to work as well.).
The JAVA installer gave me no custom install option and I ended up with a whole host of trial-run Windows Office junk as well; I even turned OFF the Ethernet switch prior to installing.
What WASP does with a single click is pretty much what I just described in the paragraph above; you tell WASP to let you see the pictures and then tell it to put things back as they were so the camera will boot into CHDK.
This whole scenario is nowhere near as complicated as it was to explain.
Now....., I can see and access my wonderful new RAW image files; I fire up DxO and it will not acknowledge any flavor of the RAW files I have just created, not the CHDK RAW, nor either version of the DNG.
So......., there goes that plan down the drain.
What I did find out is just about any image program that employs DCraw will digest all three flavors of these files with no complaint; the ones I have successfully tried thus far are RawTherapee, RawHide, and ChasysDraw; all of these programs are absolutely FREE while big bucks DxO let me down and will not accept these files.
Another fact that I discovered, the CHDK RAW files are completely void of EXIF or any other metadata; no timestamp, no camera information, nothing.
The DNG files retain all of the metadata.
I am not professional enough yet to make such determinations; but, to my simple untrained eyes, I can see no difference in image quality between the CHDK RAW and the 1.3 DNG images.
What this means is that I will keep my CHDK set to capture 1.3 DNG.
One more fact I discovered is that when using CHDK, and capturing RAW, whether it be CHDK RAW or DNG, the camera will always also produce a matching jpeg of whichever compression and quality that is set in the Canon camera menu; so, you get a RAW and a matching jpeg for each shot.
One very important little detail: if you want the camera to automatically fire up CHDK when you turn the camera ON, the little "Lock" switch on the SD-card must be set to Lock; to put the card in the reader to see and manipulate the images, the switch must then be set to unlock; then, always remember to set the switch back to Lock before putting the card back in the camera.
