This past weekend several of us on the HD View team participated in the Yosemite Extreme Panoramic Imaging Project. The project was the brainchild of Eric Hanson and Greg Downing of xRez and Greg Stock, the staff geologist at Yosemite. Greg is studying rockfall behavior on the walls in the park. Today when a rockfall happens it can be difficult to piece together, from the debris, where the fall came from. Having ‘before’ pictures of all of the Yosemite Valley walls would give Greg a powerful rockfall forensic tool. Thus was born the project. Greg and Eric wrote up a proposal, got out their Rolodex, and rounded up sponsors and volunteer photographers to make this happen.
The plan that the xRez team hatched went beyond simply taking high resolution photographs of each wall in succession. Rather, they wanted to photograph the entire valley in as small a time window as possible. Doing this means that all of the images would have very similar lighting, thus any composite image that is generated will be more seamless. The goal is to create a seamless mosaic of all of the valley walls. Because the source images are shot from multiple vantage points, the result will be a ‘multi-perspective’ mosiac. To do this, xRez will project the images onto a 3D model of the valley and re-render the images using a virtual flying ‘slit-scan’ camera. I did a quick web search for examples of this technique. I didn’t find a good example for 3D terrain, but I did find some of street-side scenes:
Capturing all of these images simultaneously required lots of gear and lots of bodies. xRez got 70 photographers to donate their time last weekend (Peter Duke has a great Flickr set of some of the Yosemite shooters). They also rounded up a good set of sponsors. Canon loaned G9 cameras, Bogen loaned tripods, Lowepro donated their Flipside 300 packs and Gigapan loaned their robotic pan tilt heads. For the shoot each G9 was outfitted with a Canon TC-DC58C tele-convertor and a home made lens hood (see Gavin Farrell’s shots of the final setup here and lineup of packs here).
The Photosynth team at Microsoft was happy to help out with financial sponsorship and members of my team flew down with our large panorama rig to man one of the 15 shooting locations. Most of the photographers hiked into their locations. Fortunately, the gear I described above was nice and portable. I believe that the longest hike was done by the team that went up Half Dome. All of the photographers were in place at 1PM on Sat., May 31, and everyone started to shoot simultaneously.
Our rig, pictured to the left, didn’t lend itself to hiking, so we drove it up to Glacier Point. Some technical details of our gear: Meade telescope donated a telescope mount from which we removed the optical tube. We put in its place a Canon 1Ds Mark III and a 100-400 zoom lens. This setup was controlled by a laptop.
We parked ourselves at Glacier Point for 1.5 hours. (I apologize to the tourists there that day for whom we denied the sweet corner spot) Over that time, we shot 680 x 22MPixel images at 400mm. Accounting for some overlap between images, this should result in a 10 Gigapixel composite. Since this is just one of 15 locations, the final result of everybody’s photos should yield many 10s of gigapixels.
Everyone converged back at camp later that day for a nice catered dinner and keg by the campfire. From the discussion at dinner, all of the gear performed very well. It sounds like there might be 100% success rate for the shoot! Kudos go out to xRez for managing the logistics of this so well and Gigapan for the reliability of their pre-release units.
I’m really looking forward to the final product which should be ready sometime in late summer. So stay tuned to the project page here. Also check out the xRez Yosemite Shoot Flickr group for photos of the weekend.