>Well, I just looked into the LViewPro and 2.0 and see that the model they propose are for colours only. There is a difficulty to select gray colour in the colours selector they provided. I do nto know about later versions. When you switch to the HSL mode, I see that vertically they change Hue and horisontally both Sat and Lum values are changed. This produces a table of colours that is not complete (no grey colours with all 3 values equal). For example, I do not see a way there to pick up colour RGB(128,128,128) that is a pure grey colour. You can add a line of grey colours to your table separartely.

You have to open a JPG in order to see what I mean. The color picker will vary from pre-defined colors within the image to full color selection as per the type of image.

In JPG they show it quite ok. I don't know what formula they use to obtain such a result.