Dear Yawns,
I apologise for my late feedback. Unfortunetelly I haven't noticed your post.
I am answering for your question.
You are right. On all photos I am using the same substance. On the first photo, Yo may see exactly, what I get after the liquid is dry. It is black-white photo. Illumination technique - Polarized light without retarder.
On the others photos I was using the same illumination technique. I have got the colours after placed the retarder between two polarisers. They are orientated at 90 degrees to each other.
Diffrent colours I get as a result of turn of retarder.
The same photos I attached on polish forum.
