"Overdye" polyester

At my annual dye retreat I often overdye clothes or fabric with Fiber Reactive dyes. 

This will only work with natural fiber fabric. 

 I recently came across a really cute dress at a garage sale in colors that
don't falter me. It's polyester so Fiber Reactive dyes won't work.

 Since it was only $2 I thought I would experiment with 

changing the color with Setacolor fabric paint.

 I used a capful of paint and three cups of water, submerged the dress until 

the fiber was saturated and hung it outside on a cloudy day to dry.

(Setacolor will sun print, or turn white under an object the is blocking the sun, http://www.dharmatrading.com/info/sun_paint.html)

 It dried too yellow to suit me... 

so I repeated the process with diluted cobalt.

I'm pleased with the dry color.

 The hand is slightly stiffer but it's still wearable.