Thanks to those who participated.
There were suggestions to add some additional fields. A suggestion to add professional qualification in color area is most commonly cited.
There are two reasons why we did not include the question into the survey.
Firstly, we try to keep the survey as short as possible. Secondly formal professional qualification is not necessarily an accurate representation of actual qualification. For example advance amateur photographers may possess quite high level to technical knowledge in the color area, while they may not professionally associated with the area.
Still thank you very much for the suggestion. Some of them are already incorporated in the survey.
with other people equipment. I belong to neither of them. ))...