There is this topic on flickr; link:

of course colors are not that great, and very faint.
Nonetheless i didnt understand the process well, can someone explain me better step by step, and tell what's the effect of each chem, the old roll is used for agin i didnt understood, and also the betadine an day light.
I am thinking of doing this with caffenol(coffee and sodawash only) instead of hair dye, would this work?