I am often asked if watercolour pans be filled with colour from watercolour tubes?
An artist I spoke to about this says:
'The way I feel it behaves when I've filled with tube colour is its state of fluidity. When I'm on a painting trip in a warm country to paint 'plein air' my tube colours like the Cadmium colours tend to be very runny and so I have to be careful when I carry my palette in my art bag. I once opened my palette when I was painting and my cadmium orange had run out all over the place - so now I just make sure I lay the palette flat inside my bag'