Oh I see.
I thought that you meant that the images were REALLY green :-)
I don't think you have anything wrong; merely that the developers of Dt
don't know exactly what the JPEG engine inside of our cameras does. The
"Olympus Like Alternate" is someone's best-guess as to how Oly maps the
linear sensor data in the raw file to color values; it's clearly not
identical.
It is strange that the marked white balance in the raw file doesn't
actually seem to be the right one. I suppose it's worth checking whether
the camera's white balance settings are being interpreted correctly by Dt?
I find that I get similar results with your raw image if I choose
"incandescent" from the white balance choices in Dt.
On Fri, Jan 31, 2014 at 1:45 PM, Štěpán Roučka <[email protected]>wrote:
> Dear Artur and Matt,
>
> thank you for replies. The color picker says that the blue channel
> multiplier is smaller in the images from darktable compared to camera
> jpegs. Example RGB readings:
> darktable - (136, 106, 68)
> camera jpeg - (137, 106, 78)
>
> You can see a comparison of darktable export vs camera jpeg here
> https://www.dropbox.com/s/0tmosar1pfw47tm/20131227-021432-compar.jpg
>
> The original files are available here, if you would like to check it.
> https://www.dropbox.com/sh/rey2xlewz1y8j45/1yjWQf-k2S
>
> When I import the both the jpeg and raw into darktable, they have visibly
> different white balance as can be seen in
>
> https://www.dropbox.com/s/5o11xbisn3iybew/Screenshot%20from%202014-01-31%2020%3A34%3A00.png
>
> Bottom line:
> All pictures here are using "camera white balance", "olympus like
> alternate" base curve and no other plugins. The issue appears in daylight
> as well as in artificial light.
> I didn't calibrate my display, but from comparison with professional
> prints of photos that I prepared, it appears that the factory calibration
> of the display (EIZO PVA) is quite good. Nevertheless, it shouldn't play a
> role in this issue.
>
> Best regards,
> Stepan
>
>
> On Tue, Jan 28, 2014 at 11:28 PM, Matt Feifarek
> <[email protected]>wrote:
>
>>
>> On Sat, Jan 25, 2014 at 9:50 AM, Štěpán Roučka
>> <[email protected]>wrote:
>>
>>> I have recently purchased the Olympus E-M5 camera and the raw files
>>> developed with darktable have green color cast in comparison the jpegs from
>>> camera. I am using the default settings: "olympus like alternate" base
>>> curve, "enhanced color matrix", and "camera white balance".
>>
>>
>> I have this camera, and have used it with Dt for more than a year now...
>> I've never noticed this.
>>
>> I'd look at your display profile settings, and make sure they aren't
>> strange.
>>
>> Also, a clue might be: what happens if you import the SAME IMAGE both as
>> RAW and as JPEG, does the JPEG exhibit the same color cast? If so, this
>> would indicate something more globally wrong...
>>
>> If you like, send me a raw file, and I will pull it up and see if I have
>> the same problem... I can do a screen capture. Off-list, of course.
>>
>
>
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