Canon Powershot SX 150 regression in colors 5.5 vs 5.3?

ggc · April 7, 2019, 7:50am

I was trying to develop some old files taken with my Canon Powershot SX 150, using CHDK, and converted to DNG (from DNG, in order to save a lot of disk space) using Adobe Dng Converter.

At the begin i was thinking about camera bad colors, but i have just tried with Raw Therapee 5.3 (from ubuntu 18.04 repos) and it delivers much better colors than 5.5 appimage.

Files here (exposed to the right, so even the jpeg is a bit washed out): https://we.tl/t-KfIXinZY5h

Screenshots, using neutral profile.

Thank you in advance.

betazoid · April 7, 2019, 8:13am

the second screenshot looks more correct
I am guessing in the first one the base table is active in color/color management/dcp, which should not be the case when profile neutral is activated or the tone curve or something like that

ggc · April 7, 2019, 9:45am

The color tab looks the same (camera standard).

I think there is something that has changed in the DNG reading, and i find really difficult to get pleasant colors with 5.5 .

darix · April 7, 2019, 1:57pm

providing raw file + pp3 might help

ggc · April 7, 2019, 2:19pm

The raw file is linked in the first post, report here: https://we.tl/t-KfIXinZY5h

pp3: neutral profile.

gaaned92 · April 7, 2019, 4:53pm

@ggc
I tested 5.3 vs last dev build

if I use in both input profile/camera standard, the two images are very different: dev image is washed out.
if I use in both input profile/custom and I select the same DCP, I get the same output.
As it seems there is no DCP for powershot SX150 IS in Adobe DNG converter 11-2-1, I choosed DCP for SX1 IS.

betazoid · April 7, 2019, 5:25pm

anyway the second one looks “neutral”, i.e. right

mannikon · April 7, 2019, 5:26pm

Opened your DNG in RT final release versions 5.4 and 5.5.
Identical and like your second image above.
With Auto Levels only, both appeared as your first image.

heckflosse · April 7, 2019, 6:57pm

I guess its related to this issue

@agriggio How do we solve this case. Is just a camconst.json entry needed?

agriggio · April 7, 2019, 7:11pm

if I were to do this “in the void”, I’d forget about backwards compatibility and try to stick with the dng specs. in the RT case, this is probably not what users expect, so it’s a tougher call… probably camcost is a good solution – but I haven’t actually tested this specific case

heckflosse · April 7, 2019, 7:52pm

@ggc

Can you try to change the entry for your camera in camconst.json from

    { // Quality C
        "make_model": "Canon PowerShot SX150 IS",
        "raw_crop": [ 26, 10, 4364, 3254 ] // cut 2pix left and right
    },

to

    { // Quality C
        "make_model": "Canon PowerShot SX150 IS",
        "dcraw_matrix": [ 13481,-4867,-1063,-2074,9960,2472,-170,1474,3894 ],
        "raw_crop": [ 26, 10, 4364, 3254 ] // cut 2pix left and right
    },

please?

nosle · April 7, 2019, 8:20pm

Would it be possible to be more explicit when dng matrix is active. Manual override? Currently you can only really know if there’s a camconst but not really if adobe or dng matrix is active?

ggc · April 7, 2019, 9:07pm

Sorry for asking, but where should i put then the file?

I have tried creating a file called camconst.json with the text below in the same dir of the option file (~/.config/RawTherapee) but nothing changes.

{ // Quality C
    "make_model": "Canon PowerShot SX150 IS",
    "dcraw_matrix": [ 13481,-4867,-1063,-2074,9960,2472,-170,1474,3894 ],
    "raw_crop": [ 26, 10, 4364, 3254 ] // cut 2pix left and right
},

I’m using the 5.5 appimage. But now i can also try to compile from git.

Thank you.

heckflosse · April 7, 2019, 9:11pm

I don’t know for appimage if it’s possible to change the camconst.json file at all. @Carmelo_DrRaw knows.

If you compile from git just look for the camconst.json in folder rtengine of your git source and change the entry as mentioned in my post. Then build and it should work.

paperdigits · April 7, 2019, 9:17pm

If you want to test, you can extract the content of the AppImage:

./RawTherapee.appimage --appimage-extract

The content will go into an AppDir folder and you can change internal files.

agriggio · April 7, 2019, 9:18pm

imho they should be treated like an embedded profile, and applied only when selected explicitly, rather than being silently applied when “camera standard” is set. that would make things much more streamlined. however, it might break backwards compatibility…

heckflosse · April 7, 2019, 9:19pm

I’m on Win7

paperdigits · April 7, 2019, 9:20pm

Sorry I meant the royal you or you all, not you personally.

heckflosse · April 7, 2019, 9:21pm

Backwards compatibility should get less importance in future imho…

agriggio · April 7, 2019, 9:33pm

I agree 110%