Problems with Canon CR2 raw decode in ufraw/gimp

[Giles Orr]

On 5 December 2012 18:28, Walter Dnes <waltdnes-SLHPyeZ9y/tg9hUCZPvPmw at public.gmane.org> wrote:
>   The raw file decodes to a garish "monochrome" blank and pink.  Help!!!
> I've recently gotten myself a new toy http://www.henrys.com/66453-CANON-POWERSHOT-S100-IS-BLACK-12MP-5X-WIDE-ANGLE.aspx
> Despite the fact that it looks like a standard consumer point-n-shoot,
> it has a larger-than-average sensor, goes up to ISO 6400, and shoots
> raw.  The most major linux annoyance is that it does not show up as USB
> mass storage device.  I solve that by reading directly from the memory
> card.
>
>   The problem I'm having right now is that the ufraw plugin for GIMP
> decodes the CR2 raw file to a garish, monochrome, black and pink image.
> I tried a few test shots with auto-white-balance, and the JPEG versions
> look fine.  The EXIF data on the JPEGs confirms that I used auto white
> balance.  The JPEG versions of the images look OK.  As a matter of fact,
> gqview decodes the CR2 files OK when viewing them.  The problem appears
> to be UFRAW (and/or the underlying DCRAW code, which I also tried in
> standalone mode and got pink images).
>
>   Google searching was useless.  Apparently, this was a known problem in
> UFRAW 0.13, and fixed in 0.15.  I've got 0.18 on my system.  The generic
> solution on Google appears to be to use a CR2-to-DNG conversion utility,
> and then work with the DNG version.  Do you know of any convertors that
> run under linux?  I'd even settle for free Windows utils that run under
> WINE.
>
>   For the time being, I'm playing around with RawTherapee
> http://www.rawtherapee.com/  There's even an ebuild for Gentoo linux.
> It appears to load and decode the CR2 file OK.  It can then pass the
> result to GIMP as a 16-bit-per-pixel TIFF file.  There's a warning that
> GIMP truncates the data to 8-bits-per-pixel, but it seems to work OK.

Hi Walter.

This isn't the answer you're looking for, but I hope it'll be of some
help.  I've been a dedicated fan of Canon since long before digital
cameras even existed, and a dedicated photographer before that.

My take on this is that you should think long and hard about why you'd
want to shoot RAW.  I know it has advantages and maybe you need some
of those, but if you end up converting your images to TIFF and are
happy with that, you've lost about 95% of the advantages of RAW.  I've
shot digital for about eight years now, and have chosen to stick with
the highest quality JPG files that my cameras could produce rather
than worry about RAW.  Several reasons: RAW requires roughly 10x the
storage, and my photography is already taking up enough space on my
hard drive, DVDs, and various other external storage.  Hand in hand
with that problem is that storing the image on your camera takes
proportionately longer, significantly increasing an already too-long
inter-shot time.  Linux handling of RAW has been pretty much crap from
the get-go, and I simply don't see enough advantage in RAW even if the
other problems were solved.  But I admit I've never even tried to
experiment with it.

I'll add that I've voluntarily stuck with high end point-and-shoot
cameras rather than moving to larger sensors and DSLRs - mainly
because I'm not willing to carry the extra weight and bulk of the DSLR
and a couple lenses.  Note that small sensors are effectively what
make "superzooms" possible - and those are a huge blessing when you're
travelling.  I pay the price in low light, but have become a huge fan
of my hiking stick/monopod.  :-)

-- 
Giles
http://www.gilesorr.com/
gilesorr-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org
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