[arriu]

If you want to extract the actual raw data, dcraw doesn't really advertise the way to do it. Many of the options for extracting the data still apply some processing/conversion to the underlying data.

It is a pretty big mess actually. Each manufacturer has different constants that need to be applied to the data, so the raw data from one device is not comparable to another. Convincing dcraw that you actually want the unaltered data is not straight forward.

Anyways, if you really do want to see the raw image, there are a few undocumented flags you can use.

> dcraw -E -4 -T *.CR2

This will give you an unprocessed 16-bit tiff file containing the "raw" data.

What is interesting is that some camera sensors capture data slightly beyond the image you are presented with. The camera will crop in and debayer the image for you, as will your image editor.

See this thread for hilarious lengths people go to in order to get unaltered data from their sensors (monochorme converting a dslr):

https://stargazerslounge.com/topic/166334-debayering-a-dslrs...

[bufferoverflow]

That thread is more about removing the physical filters from the DSLR sensors - RGB, UV, infrared to achieve higher resolution and much higher sensitivity.