PeterMoretti wrote:I've never been able to get the color card matching to work with any kind of satisfactory result
It depends on what you expect as a result. It does
not automatically compute a 3DLUT-like correction that places all the color patches on the calibrated pattern within 0% of the known target values. It
does attempt to neutralize the grey scale, depending on how well lit the chart itself is, and then displays an error value, showing where the spectral deviations are. If you added another node to your correction tree, improved the secondary hue values, or in fact, the grey scale deviations, then added another node and re-performed the chart correction to generate another chart/reference test, then recursively fixed your intermediate node, you could, in theory, generate a Look-Up that would compensate for all the lighting inconsistency, lens flare, non-uniform spectral density of your lighting source(s), the transfer function of the light-gathering sensor, its PROM/error compensation, the camera's internal matrixing, the rounding errors in the media codec, couple of hundred other factors...
For that setup.
Then you would get to do that all over again if you change the lighting, exposure, lens, metadata...
Charts are great for a couple of things. People who have never done this before can benefit, and those who have the experience and skill to do it right and understand what it is that the cards signify can communicate many intentions with judicious use of the card and clear notes to anyone who needs to interpret the card.
They are not that useful for precision auto-correction unless the cinematographer is bullet-proof. Usually by that point, though, they will have sorted out that its just easier to bypass the tool and read the scope.
jPo, CSI