Balloon

Last night in town to find road closures but not many arty light installations, in fact just the one at Oxford Circus, up and running at 2200 on Friday evening. The one which escaped to much media noise a week or so ago.

So we had a spherical balloon, perhaps as much as 4 or 5 metres in diameter tethered above the middle of Oxford Circus, more or less as shown here, with this picture being taken from Twitter. Not the first time I have been there, but probably the first time I have taken anything away. Found for me by Google, on this occasion doing a better job than Bing.

A bit of fun, but I am not sure about spending a lot of money on it, despite the seeming enthusiasm of the reports on Twitter. But I do wonder about how these swirling patterns were made, in appearance reminding me of the (psychedelic) lights shows you used to get at discos in the early 1970's, made then by shining light through moving mixtures of immiscible, multi-coloured oils. Probably an oxymoron but hopefully you can see what I am getting at.

But those displays were made by simply pouring small amounts of suitable oils onto a glass plate, or perhaps between two glass plates, stirring them up somehow, and then projecting the results onto a screen or onto the walls, a proceeding which is clearly not going to work inside a sphere. I assume that some sort of projection is involved, but how do you project a plane image onto the inside of a sphere without the joins showing? Does it require a great deal of computer power and the sphere to be kept very still, so that the stable joins can be computed? The catch with this notion being that I could not see any joins, and there are none to be seen in the snap above.

Or, seemingly equally far-fetched, does the balloon have two skins, with the mixtures of immiscible, multi-coloured oils being contained between them and being stirred up in some cunning way? But with projection being quite simply accomplished with lights at the centre of the sphere?