Tag: Dave Hunt

Time lapse video, for art and for science

Dave Hunt (a familiar name in these parts) has been working on perfecting his Raspberry Pi-controlled camera time lapse rig. Before I go into any more detail, here’s some absolutely stupendous video resulting from his work on the setup. (I recommend you use HD when viewing this – and watch the video in a full-screen setting if you can.)

We’ve featured a few projects here which use the Pi to create time-lapse video, but Dave’s is the most sophisticated we’ve seen yet, adding features like a heater to evaporate dew from the lens and an ability to film rising or falling sequences. There are some great pictures documenting the build at his blog (we’re very impressed by the neatness of the construction work), along with some circuit diagrams and the Python you’ll need to create your own rig. Visit Dave’s site for a tutorial and discussion about construction.

We’re very encouraged to see so many artists using the Pi, in so many different ways; there have been a number of art installations featured here, and it’s really great to see the Pi driving the tools needed to create beautiful things. Computing is as much a creative discipline as it is a scientific one – that’s a message we at the Foundation are very keen to get through to kids, but it’s not one we’re seeing reflected in schools.

Science can be beautiful too, though. Over in the United States, SaratogaWeather has been using a static camera controlled by a Pi to take time-lapse video of the weather patterns over Mount Timpanogos, Utah. Dynamic systems like the formation of clouds are hard to appreciate and study at real-time speeds: but speed things up a bit, and patterns and structures become evident and much easier to analyse.

There’s a whole channel full of these videos, and cloud geeks like me will have great fun with them. I irritated everyone around by shouting “CAP AND BANNER!” at the top of my voice when I spotted one in another of these videos. (Once I nearly made Eben crash the car by screaming “Stop! KELVIN HELMHOLTZ!” while we were travelling at speed down the A14. I blame hanging out with fluid dynamicists. Kelvin Helmholtz instability produces a great and rather rare cloud formation, though – I’m still proud to have spotted one.)

What applications would you like to see time-lapse cameras being used for? Are you working on something yourself? We’d love to hear your thoughts.

Focus-stacking with Raspberry Pi for macro photography

Dave Hunt is on a bit of a roll at the moment. Not content with having engineered the water droplet photography setup behind the prettiest post we’ve featured here, he’s also been working with the Pi and an home-made macro rail for sharper macro photographs without all that woolly depth of field. Bokeh – the fuzzy blur from the out-of-focus parts of a picture – is an effect that can be really beautiful, but sometimes you want a sharper picture, which can be nigh-on impossible in macro photography without special equipment.

Dougal, this cow is small. Those ones are far away.

There’s a way professional photographers deal with this, but, of course, it’s expensive. You can buy a rig which allows you to take many images, each taken a little closer to the object, so different parts of it are in focus with each picture. You can then combine or stack all those images in software, as in the cow picture on the right. There’s an open software solution to the matching and stacking problem called CombineZ (somebody port this thing to the Pi; that GPU is built for just this sort of application), but if you want to buy a rail that automates the moving of your camera, things suddenly start to look expensive. Dave says commercial solutions come in at around $600.

Enter the $35 Raspberry Pi and an old flat-bed scanner from the loft.

If you want to build your own focus-stacking rail, Dave has full build instructions, including circuit diagrams, code and tips on where to get parts at his website; even if you’re not a seasoned electronics hacker, you should be able to follow his very clear instructions if you want to make your own. Thank you Dave, for another great money-saving photography project and a fantastic writeup. We like your cow.

Water droplet photography

We knew when we were designing it that the Pi would make a great bit of digital/real-world meccano. We hoped we’d see a lot of projects we hadn’t considered ourselves being made with it. We’re never so surprised by what people do with it as we are by some of the photography projects we see.

Using a €15 solenoid valve, some Python and a Raspberry Pi to trigger the valve and the camera shutter at the same time, Dave has built a rig for taking water droplet photographs.

Click the image to visit Dave’s site for instructions.

I remember the first time I saw droplet photographs as a little girl back in the early 80s,  in one of my grandma’s National Geographic Magazines. Back then, this sort of technique was completely out of the reach of the amateur photographer. Now, it’s actually very cheap to set up yourself, and surprisingly simple.

Dave has documented everything he did to make the setup; it’s very approachable, and even if you’re a photographer with little electronics experience, you should be able to make your own. Visit Dave’s site for full and easy-to-follow instructions – and let us know how you got on!