This image shows the liquid tube watercolor cobalt blue hue applied to the lime putty before mixing.The original darker tone can be seen,the lighter blue dry panel above is the cobalt pigment after reacting with lime.One of the difficulties with fresco painting is that every pigment reacts differently with the lime.Some appear darker on application and dry much lighter,some absorb more and are more saturated,some colors grab darker.It can be described in some ways as painting into the future,as I can't paint with what the colors currently are as they are applied,rather I have to imagine what they will be once dry.This proves to be very difficult as there are so many factors involved,such as what happens when colors are mixed using the addition of white,or with two or more pigments.Some pigments will dominate others.This also makes obtaining a value range difficult.In order to render images effectively,control of light and dark is very important.So I began to experiment with making smaller panels of various colors to teach my eyes to recognize how the pigments will change.