NASA explains why they chose a 2 megapixel camera for Curiosity
We heard a lot of people criticize the images sent from mars by Curiosity, considering that it is likely that the smartphone camera in your pocket you have a higher resolution than that of the advanced rover, with only 2 megapixels.
While on Earth we have data networks that allow us to send high resolution photos from the cell, on Mars, Curiosity to simply rely on the UHF.
“The UHF antenna transmits the two spacecraft orbiting Mars, which in turn sends the results back to Earth. From there comes the most data. This gives us about 250 megabits per day, which must be shared among several instruments, so there is not much bandwidth for the cameras, “said Mike Ravine, in charge of the chambers of the Rover to Digital Photography Review .
Exactly, lets you send photos only 31.25 MB in a day – less than 1 GB per month.
On the other hand, it was decided to use the same sensor Kodak Kai-2020 into four chambers: MAHLI, the two Mastcams and MARDI, to reduce costs and facilitate the work, by not having to test and adjust each one separately. He was also the smallest sensor available when working on the project can capture video in 720p HD.
We also analyzed other options, but Ravine said that “the state of the CMOS sensor was not credible in 2004. They are an attractive option today, but they were then. “
Despite the low resolution, that should not be a problem, says Ravine, as Mastcams can take several photos and stitch them together in multiple exposures. “A mosaic produced by a camera with higher pixel count does not provide the benefits we receive,” he concludes.
360° image sent by Curiosity is composed of 130 low-resolution photos (114 X 144 px). Curiosity is expected to send some specific frame of this panorama of 1,200 x 1.200px soon. “After a year stored in the cold, where they endured the rigors of launch, the trip to Mars and all that happened on landing, it’s great to see that the cameras are working as planned,” said Mike Malin, Mastcam researcher at NASA.
Although a great achievement to receive color pictures from Mars, NASA’s Ravine itself regrets that they are unable to include cameras with zoom and 3D prepared by James Cameron . The problem with these systems was to create unused liquid lubricants, which require energy to heat constantly use the cameras during the frozen Martian night.
– Mars rover project manager Explains camera 2MP camera choice (Digital Photography Review)
– NASA’s Curiosity Beams to Color Back 360 of Gale Crater (NASA)