A challenge...

[Chataignier]

Firstly, this was all done in camera with one exposure - no photoshop etc at all, just the usual optimising in L-R.

Secondly, your eyes do not deceive you, the backgound was vertical

So, how was it done ?

[Wavelength]

Nice effect; did you spread a raw egg on a glass plate and seeing some design beneath?

[Antonio Correia]

Quite interesting...

[Chataignier]

Didn't take you long ! Yes it was a glass plate in front of the background - quite a challenge to light it without creating reflections.