Tracks on Mars
by JackDesBwa 2019-09-11 06:54
The Curiosity rover currently on Mars planet sends photographs of its cameras on a regular basis. They are automatically added to a public repository when they arrive. Of course, they are often of low interest for the wide public.
Due to low bandwidth and low signal, a lot are lost and most are transmitted in low definition, low resolution, low quantification, black and white. Most cameras are b/w anyway. There are several stereoscopic cameras onboard and sometimes the two parts of the pair manage to come back to Earth.
I found two corresponding shots with quite interesting photographic content. They were taken on SOL2449, which converted to Earth time is 2019-06-27. The bare photographs can be found at https://mars.nasa.gov/msl/multimedia/raw/#/?slide=2449 and are credited to NASA/JPL-Caltech without copyright. The cameras are separated by approximately 42cm, with f/12 aperture and a 37mm-equivalent lens (45° field of view).
There is quite work to go from bare images to such a stereo picture, mainly because of the quantification and levels mismatch. However the longest part is definitely to find matching images in the first place.
-- 2019-06-27, Curiosity navigation cameras
JackDesBwa 2021-02-27 15:51
And with the new rover Perseverance, there are color ones now. :-)
Well, technically, the mastcam of Curiosity was already a color stereocamera on Mars, but the two eyes have fixed unmatched focal length, which limits their usage for stereo views.
By the way, I wrote that "the longest part is definitely to find matching images in the first place", but since a few days, I made a tool to match (most of) them automatically: https://mars.stereopix.net/
Of course, you still have to process them for having a nice stereoscopic photograph, but the tool allows to preview the pairs.
LaurentD 2021-02-22 17:47
Excellent! I am pleased to see that the NASA is using stereoscopic cameras.