Shooting to RAW with Canon A-series PowerShot (DIGIC II Only)
Advantages of raw shooting (A610 samples)
Why (and when) do i need raw support on my PowerShot?
Crop of image overexposed by +1/3EV (to capture shadow areas). It is easy to see the "dcraw.exe" preserves more hihlight details. "dcraw.exe -H 9" mode successfully restored the clipped red channel, so resulting image preserves all the details in both green and blue channels, and most in red channel. You can't get even close to this result using camera jpeg as a source (jpeg | dcraw | dcraw -H 9)
Red and green channels swapped to get the fase a marsian view :-) (jpeg | dcraw | dcraw -H 9)
Slightly overexposed (therefore desaturated) sky, false blue tree branches. dcraw solved both problems, even without highlight recovery mode (jpeg | dcraw | dcraw -H 9)
Example of scene with extremely wide dynamic range. Camera fails to preserve full DR, even in raw mode.
But using RAW, you can get rid of lost saturation in deep shadows. "dcraw -H " cannot recover most of details, because all channels are clipped. But anyway, the highlight improvement could be seen as well. I have applied Adobe Photoshop CS2 function "Shadows/Highlights" to compress DR and make an image look closer to what i see. [Amount=100; Tonal_width=50%; Radius=160pix; Color_correction=+20%] - for all images: original jpeg, 8bit "dcraw" output, 8bit "dcraw -H5" output (jpeg | dcraw | dcraw -H 5)+Photshop
100% size crops. Shadows. RAW superiority is evident. Noise can be filtered by NeatImage or Noice Ninja, but you can't recover the saturation lost in in-camera image processing workflow. (jpeg | dcraw | dcraw -H 5)+Photshop
100% size crops. Highlights. You can recover some details from RAW. (jpeg | dcraw | dcraw -H 5)+Photshop