community of dyers

Hi there, I hope someone can help with this problem. I tried dyeing sinamay with acid dye which turned out very badly. I was informed that I should be using Procion dye and so tried that this morning. It was going very well, the colour was just what I wanted until I dried the sinamay. I hung it on the line - just for 10 minutes in the weak Welsh sun - and it changed colour, from a lovely red violet to a much bluer colour. It also went very dull and flat and the colour was very patchy. There are remnants of the original colour where the pegs were which made me wonder if it was the sun but I have been advised that its unlikely. I actually got pretty much the same disasterous result as when I used the acid dye.

I have deadlines to meet - a number of different colours to dye. I hope you can help.....I am getting a little panicky.