Huge self-portrait of Curiosity on Mars
Posted By Emily Lakdawalla
01-11-2012 19:27 CDT
This is spectacular. Curiosity used MAHLI, the scientific camera at the end of the robotic arm, to shoot a huge color portrait of herself sitting on Mars, with Gale's central mountain in the background.
Enlarge it, seriously, it's worth it.
This is the second version of this image that JPL has released today. The first was this thumbnail version. Notice something different about it, other than the lower resolution?
The two versions reflect different compromises made in the challenge of representing a three-dimensional world on a two-dimensional screen. No matter how you try it, there's going to be some kind of distortion. The bottom (thumbnail) version does a better job of representing the rover at a constant scale -- the wheel that is closest to you appears larger than the back wheels, but it's larger by the amount that it might look larger to you if you were standing there. In the top image, the closest wheel is really distorted and big. But, on the other hand, the top image does a better job of showing the landscape, with the horizon flat and the mountain rising behind the rover. The bottom version has a significantly curved horizon. For a variety of other approaches at dealing with this projection issue, visit the thread dedicated to this image at unmannedspaceflight.com.
Here's another cool thing about the image. There are reflective surfaces on the rover. Two of these, at the top of the mast, show reflections of the turret, the part of the rover that was taking the image. The rover photographed itself photographing itself. The photo of the turret taken by the left Mastcam was taken just 30 seconds after MAHLI photographed the left Mastcam.
And they're not done yet. On sol 85, they took a second complete self-portrait at a slightly different angle. That means they have this color portrait in 3D! Producing a 3D image is going to be really challenging because of the projection issue. Here's Stuart Atkinson's first attempt at it, using the thumbnail images that have come down so far. Stay tuned for more!