Thanks for answer, Nicolai. If I understand it correctly, raw imagedata is the same, no matter who pick it up (fCam or camera-ui). So, fCam creates .dng file (from mentioned raw imagedata) differently? It is even possible?

Of course I mean image data itself, not thumbnail, that must be different - this case is very clear, and thanks again for explaining.

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Fortunately, CornerFix does awesome job on (lossless) getting rid of cyan vignette, so we've overcome the biggest obstacle of getting high-quality images from RAWs. Furthermore, CornerFix is FOSS, so there is a chance that it's going to be ported to N900 (which, in tandem with ufRAW, supply us with whole 'photolab' on device).

I'm pretty sure, that other things, resulting in "better" coloration on jpeg's created by closed-source components, are just matter of proper advanced image processing in RAW developer, and with some work involved, we can create even better "general purpose" set for developing our RAW's (such profile - for example, ufRAW compatible - can be freely distributed), + still having possibility to manually tweak every image (with or without applying generic profile first), if desired.

Thanks for making mthis dream come true - without Your work on camera-ui, it wouldn't be impossible (fCam still lacks many parameter possible in camera-ui)!