[image title=”tank1″ size=”thumbnail” id=”436″ align=”left” linkto=”[site_url]/wp-content/uploads/2008/09/tank1.jpg” ]So I have a confession. One of the best parts of our job here at fxphd is to do stuff that we have just wanted to do for years but never had a client or a budget or a project that allowed it. One such thing is cloud tanks. I just like cloud tanks. So this week we started our first tests with them. Some — not all — but some of this work will be in next term’s fxphd courses and some will appear in Jan 09.
Now I need your help dear fxreaders. We have to work out how to do layers in the water, an old school technique of having different levels of density to the water by having salt layers. The theory is something to do with having different mixes of salt water in a still tank and then this acts as a buffer for the expanding cloud tank primary – in our case liquid latex. I know out there some of your will know of a DVD extra or an article or book that explains this, for me googling salt water cloud tank inversion did not get me much – I did find this on the Raider of the Lost Ark site:
“They created an inversion layer in the tank using different temperatures and densities of solutions, for example a layer of salt water on the bottom of the tank with a layer of fresh water above it. Various pigments and dyes could float in the plane where the two layers meet thereby generating different types of cloud effects. They used what they called an ‘atomic arm’ (a remote-controlled hand, such as the ones used for moving isotopes in nuclear laboratories) to squirt pigment into the tank at the appropriate level. It is designed so that someone can control the insertion of the pigment from back near the camera, so he can see pretty much what the camera sees as he makes a shot. ”
My problem is how do you create such a layered effect without it just all mixing?? So if please hit your old copies of cinefex and email or post here any techniques on how to do this… we have just started our journey but this is uncharted old school techniques. I have no experience in this, I am having to re-learn some nearly lost skills from our visual effects playbook.