Saturday, May 9, 2009

The High Speed Liquid Observation Platform - V2.0

As you know from the previous posting, I solved the problem of getting enough light to do high speed videography using a new LED light ring that just became available.

It then occurred to me that this new lighting form-factor would allow me to radically simplify the experimental platform I had previously built. In the previous design, I used a rectangular cage because I was expecting to have to mount linear light strips to the device. However, the light ring mounts directly to the camera itself, which means that the platform now only has to perform two functions:

1) Allow me to easily point the camera at what I want to record.

2) Collect the water globes at the end of each Zero-G cycle.

This permits a much more elegant design, as follows:

Basically, the new device is a pistol-grip for the camera, with an extension that holds an open Zip-Lock bag (optionally with a diaper in the bottom to absorb water). The grip is made out of two short sections of aluminum t-slot, and the ring that holds the bag is made out of thin, flexible UHMW plastic, with some velcro to hold the bag in place. Everything is wrapped in adhesive-backed foam.

Another nice touch in this design is that the far edge of the collection bag ring is a visual reference that can be used to keep the camera the correct distance away from the water globes; all I have to do is prefocus the camera to the correct distance and everything will work out just fine.

It isn't easy to see but the camera is actually mounted slightly to the rear of the pistol grip, which improves the balance a bit.

One thing I'd really like to do is get a prototype of the Zero-G Coffee Cup and test it out. But first I have to get one, and then I have to bamboozle the Zero-G folks into letting me try it. Hey Starbucks, can I get a grant for Zero-G Latte Research?

Friday, April 10, 2009

Nerds in Space!

I finally got around to cutting together a little music video from the footage of our first ZeroG flight. If you go to the Vimeo site you can see it in HD. Enjoy!

Tuesday, March 17, 2009

Let there be light!

It has been a while since my last posting, but I have been busy researching lighting sources for my next Zero-G flight. You will recall that my concern was that I could not get sufficient light inside the cabin to get good video except when next to a window, and I was looking to either buy or build something to deal with that problem.

As luck would have it, a posting on Gizmodo lead me to a new product, the Digi-Slave Flex Ring 6400 LED Macrophotography Light. After some consultation with the manufacturer, I purchased one for testing.

To my great surprise and pleasure, this little beast pumps out enough light to permit videography not just at 300 fps, but also 600 and 1200 as well! Check out the video below, the shots were taken in a totally dark room, lit only by the Digi-Slave.

The trick to getting the maximum light out of this device is to use rechargeable Nickle-Metal-Hydride (NiMH) AA batteries. While these do not provide as much voltage as regular AA cells (1.2 vs. 1.5v), they have lower internal resistance and can provide higher current flows than even "high-discharge" Lithium batteries. Enjoy!