Centriphone – an iPhone video experiment [video] | Hacker News Reader

Centriphone – an iPhone video experiment [video]

youtube.com

52 pointsprawn8 comments

Any speculation on how he did that? In some of the shots I can see the main string splitting into what looks like two strings, but I was expecting a third.

Edit: http://imgur.com/O0Z2UOM

I'd expect he's just attached a string to a phone case, and whirled it. If there were any stability issue a teeny tail-vane on one end/side of the phone would hold it in its orientation.

I keep looking at this and something is scratching at my mind about rotoscopes, time slicing and rolling shutters, and how this could be used for something, but I can't quite put my finger on what.

Edit: https://www.youtube.com/watch?v=EnrwrwMfNSs is along the lines of where my thought was going. You could make 360 video with this method, potentially extract high resolution spatial information too.

1) high shutter speed, lots of light 2) 240fps, twixtor in post 3) string splitting into 2, attached to top and bottom of the iphone, presumably stopping it from spinning around? 4) fisheye attachment

The case could have some kind of fin or tail that keeps it from spinning.

I immediately think of a thing from my kite aerial photography days called a picavet http://scotthaefner.com/kap/equipment/picavet/ a sort of angular momentum assisted stabilizing rig.

Interesting but I believe this is a different scenario. The problem here is to avoid the phone rotating around the axis of the lens. The air flow from the circular motion could be used to stabilise it when there is fin at the back of the case. In addition the axis needs to point towards the center of the circular motion. Fixing it with a string at each corner is probably enough for this.

There's 3 strings. I've seen a higher quality HD version of this movie and you can clearly make out 3 strings in certain shots.

Edit: Re-looking at this movie, there may be 4 strings attached, see at about 1:35 in the video at max resolution. 2 sets of 2 strings (one for each corner of the phone?)

For one, he used 3D printing. More details: http://3dprint.com/118780/3d-printed-centriphone-rig/

Reply on news.ycombinator.com