Here is another set of experiments, actually done after getting surprising results with versions of dcraw later than 8.11. These images were generated using: dcraw -a -n -c -h The -h switch just speeds up generating these small images for the web.

In early June, I took a trip to Utah and did a lot of photography in the red rock sandstone country. In the middle of the trip my buddy convinced me that there was no reason to be saving both raw and high quality JPEG files on my flash cards, since I could just generate JPEG files at will when I got home and save space on the flash card. This made sense, but when I got home and used dcraw 8.21 to generate the JPEG files, I got dark files with some surprising color shifts.

It turns out that the problem lies in the -n switch, which has new semantics and which I now omit. I am now back to saving both .cr2 and .jpg files till I get to feeling totally comfortable with dcraw.

The following image was taken south of Tucson, Arizona in the early morning with side and backlight. I don't think they should look this red, but the embedded thumbnail looks too blue, maybe something between the two would be right.

Here is a photo converted to JPEG using dcraw 6.35 (which is what ships with Fedora Core 4 in /usr/bin), These colors look reasonable, perhaps a bit rich in the red.

Here is what dcraw 8.11 does, which is also reasonable, but a bit different than the above, red is more subdued and greens are now nicely saturated.

Here is a photo converted to JPEG using dcraw 8.23 This is the image that exposed the fact that the -n switch has new semantics.

Here is the above 8.23 converted photo with the -n switch left out. This is much better and looks identical to what 8.11 produced. Interestingly it is not the same as the next image.

Here is the embedded 1536x1024 "thumbnail" yanked out via the dcraw -e option and not processed in any way other than shrinking via image magic to put on the web here (as was done for all the images).

Conclusions: I have a lot to learn! I think I like the output from 8.23 without the -n switch, but seeing the embedded JPEG thumbnail starts me asking questions again. I need to start shooting some photos of something well known (like a stuffed animal).