There is no new posts all over the forum for third days..
I am all confuse again about the conversion between different color spaces and different white points..
Rec. 709 standard has 6503K (x=0.3127, y=0.329) white point, let's name it D65 here. DCI P3 standard has 6302K (x=0.314, y=0.351) white point, let's name it D-cinema.
If we create a conversion LUT from Rec709 to P3 which is converting everything (colour gamut, gamma and white balance) and apply this LUT to an image this image will look absolutly the same at Rec709 display (original image) and at P3 display (image through the conversion LUT). Absolutly means if the image has some white area with balanced R, G and B channels and 6500K temperature then after conversion and viewing at P3 display this area will also have 6500K temperature. This sounds clear. Same image has the same look at different standard displays with correctly applied conversion. OK, good. But.. if we have a look at waveform monitor then white area of the image will be unbalanced (B channel has the biggest level, R little bit smaller and G much smaller). This makes sense also. So, all material converted from Rec709 to P3 will look like unbalanced and shifted to blue and magenta at the vectorscope.
The main instrument of the colorist is not the only display device but the scopes also. Doesn't this mean that the same colorist will create the different look of the image if he works at P3 D-cinema display and if he works at Rec709 D65 display. And in first case white objects will have about 6300K temperature and in the second case they will be about 6500K.
What I am trying to understand, do we need to convert the white point when converting between different formats?
Again, for example, if we are grading on P3 digital cinema projector and then converting to Rec709 copy (including the white point) the image will look absolutly the same but won't it be too grinish to compare to other material which TV people are used to see?
Sorry for my overloading the topic.. )