Are there any tech references to the internal processing of RawTherappe, Gimp, Darktable a far as bit depth while processing and accuracy of color space representation / transformations and color depth of preview on monitor?
I have a 4k Color Calibrated 10 bit laptop screen (HP ZBook Dreamcolor 4K w/ Nvidia P1000) and trying to exit the Photoshop ecosystem and its subscription / compromised artist rights eco system).
It seems Gimp for example defaults to sRGB which you can manually chage to Adobe RGB - but what about color transforms from AdobeRGB to sRGB for jpeg export?
I plan to dive into the code for those that are open source but it seems like you âcanât get there from hereâ with some file formats etc. Source files will be Fuji x-H2 AdobeRGB raw files.
Sorry if a lot of questions / software buried in there and maybe a detailed tech comparison across tools already exists that someone can just provide link for.
Thanks in advance
Raw files are never sRGB/aRGB. These color spaces are used for JPEG export only. If you set your camera to Adobe RGB the setting only applies to the JPEGs.
That makes sense but Fuji lets you set color space whether raw only jpeg only or raw+jpeg so maybe it just chages the metadata field for colorspace
I was more concerned about Darktable setting for AdobeRGB or sRGB and the limitations to colorspace while processing. But the next answer has various links so let me RTFM I have never tried to export AdobeRGB jpeg, but seems that would not display correct color to W3 which jpeg seems designed for.
Thanks very much
The setting (sRGB or AdobeRGB) affects only the JPG, not the raw (and not the metadata).
In short:
RT/ART: by default, ProPhoto RGB working space; darktable: by default, Rec 2020. Plus, depending on the software and the module: LAB, JzAzBz, darktable UCS, different LMS spaces, and more. All 32-bit floating-point.
You will not likely use adobergb again unless maybe for printing if you do thatâŚyou will edit in a wide space and then export in that side space if you do further processing or export as sRGB for web viewing or sharing⌠any in camera color setting is only impacting a camera generated file. The raw files are captured light âŚthis is subsequently processed by your chosen software⌠you are right to get to understand the various profiles used for this processingâŚ
Jpeg preview image embedded in raw file colour space
When you shoot raw only. Number 1 does not apply. Cameras always (pretty much) create a jpg before saving the raw file. Some cameras save full size low quality JPEGs inside the raw file container.
Ted, browsers are color-managing to sRGB for display by default, these days. If your image has an embedded profile, it happens. To see the actual data, you need to either turn that off, or remove the embedded profile from the image so the browser doesnât know what to doâŚ
IF you export a JPEG with an embedded profile for the colorspace that represents the data, AND IF you display that image in a color-managed viewer, the viewer will use that embedded profile to convert the image from its colorspace to the display profileâs colorspace, thus looking correct for that display.
IF that color-managed viewer is a browser, without any further configuration it will use the embedded profile to convert the image from its colorspace to sRGB, the default. IF the monitorâs gamut roughly corresponds to sRGB, thatâll look okay.
IF you export an image with no embedded profile, any viewer has no choice but to display the pixels as-delivered, no conversion. NOW, things donât look rightâŚ
Of note, the last paragraph may not apply to Wayland-managed displays, I donât really know what the heck theyâre doingâŚ
Sooooooo⌠Iâll posit that exporting a JPEG to AdobeRGB with the appropriate embedded profile might not be that bad an idea, as any color-managed destination will look right AND there arenât that many non-color-managed destinations anymore since browsers are doing the sRGB thing. Youâll get âimage looks dullâ comments from folk who download and view your image in dodgy viewers, but who cares about them?
Color management isnât that hard, but itâs not obvious and isnât explained well in most quartersâŚ
Oh, of note, you can export your images in ProPhoto and embed the profile, and theyâll look the same in any color-managed destination. Think about thatâŚ
Decent test pages⌠Iâm sure there are several others⌠my gamut is not exactly srgb so I see minor differences⌠esp say on the webkit page the umbrellaâs and in the first image the yellows in the skyâŚ
I have never tried to export AdobeRGB jpeg, but seems that would not display correct color to W3 which jpeg seems designed for.
