Woww…
Great article!! Thank you. I have to re read it carefully.
I have recently discovered dartkatable (well I have tried it long ago but it looked quite difficult for me, coming from lightroom and capture one).
I was impressed for some of its tools.
One of my reasons for selecting darktable over others was that it was 32bit float calculations in what I thought was the best color space and more related to human vision: CIE LAB.
I thought that processing in CIE LAB would be the best option and get most appealing colors.
I had not thought about problems with focusing or defocusing due to luminance being not linear.
After reading this, I understand the problem and the migration to other space where luminance is linear, and calculations would be easier and don’t produce artifacts.
I was clear for me that the working space was CIE LAB (except for the initial steps of generating colors from camera data and the last steps of generating color components of the destination device).
What I have not understood after reading is what is the color working space now in dartable 3.0 and onwards.
Are most of the calculations done in linear/additive CIE XYZ space?
Are them done in CIE xyY?
Do you use CIE RGB colors?
All seem to be linear and additive color space but I would like to know where the color calculations are done.
It seems you are using xyY from now on, is it right?
You say many of the plugins still use CIE LAB.
But then, does darkroom convert the pipeline to CIE LAB before sending the result as input to that modules and back again after getting the result from the module?
Are all those modules planned to be reconvertid to the current working space?
I use frequently frequency separation for focusing in other software.
And a high pass filter with a blending mode of linear or soft light to get more find details where I want.
But there is no radius in the high pass filter.
I had realized that many of the blending modes do not produce the same results in darktable than PS or other software.
Linear light gives you darker zones where you get lighter ones in PS.
Is it due to calculations of the blending made in the linear space and grey being 18% instead of 50%?
That is what I understood, at least.
How can we circunvent that problem to get similar results?
One of the most attractive features of darktable is being able to apply masks (with lots of options) and blending modes, over Capture One, for example, where yo do no have blending modes and masks are less feature rich.