Everything you need to know about Mars Curiosity Rover’s Cameras

If you’re wondering why the Mars Curiosity Rover isn’t beaming back High Definition videos and 32 megapixel photos, you’re not alone! Surely with camera technology these days we should be looking at 3D videos and high res panoramas. At 2 megapixels, even a standard phone today can blow the Mars Rover’s cameras into the space-dust.

Here’s everything you need to know about the Mars Curiosity Rover’s cameras.

The equipment

The Mars Rover holds 17 cameras for black and white photos, colour photos and hazard avoidance. Seven of these cameras reside on the Rover’s Mast. The most noteworthy cameras are the Mastcams (pictured below) and the Remote Micro Imagers (RMI). The two Mastcams hold a focal length of 35mm and 100mm to photograph close and mid range scenery, and the single RMI holds a 1,500mm focal length to capture the incredible detail of distant objects. According to Wired, the Rover can ‘distinguish between a football and a basketball from seven football fields away’.

The resolution and sensor

Mike Ravine, project manager for the development of the Rover’s cameras, has shared a fascinating insight into the design and development process they went through to select and develop cameras for the Mars Rover.

Mike’s team ended up choosing Kodak’s Truesense imaging chips. At the time, the chips were chosen based on his team’s ability to clock and control the sensors, and also on the size of the files produced. Big files are hard to transmit from Mars! A 4 megapixel chip was considered, but Mike noted that the 4mp CMOS would have run half as fast. The 2 megapixel sensor is quite poor by today’s standards, but at the time it presented a powerful and highly manageable option.

“These designs were proposed in 2004, and you don’t get to propose one specification and then go off and develop something else. 2MP with 8GB of flash [memory] didn’t sound too bad in 2004. But it doesn’t compare well to what you get in an iPhone today.”

“We’ve built-up decades of cumulative experience of working with Kodak and now Truesense interline sensors. We know how to clock them and drive them – they’re a very easy CCD to drive. A similar level of confidence was needed for the cameras’ memory. The flash we ended up using was because we had a lot of radiation test data for it.”

The Mars Rover uses 4 Truesense imaging chips.

The lenses and 3D cameras

The original plan was to produce 3D footage by having two cameras side by side at an equal focal length. Developing two cameras of the same specification for this purpose though would have been a waste of space, so Mike’s team looked at developing zoom lenses to increase the versatility of the 3D camera.

“They were going to be 6.5-100mm zoom lenses, which would allow us to set them both to the same focal length for capturing stereo (3D) images. However, problems designing the lens without using wet lubricants (which would require battery-sapping heating to ensure continued operation in Mars’s extremely low temperatures), proved difficult and the development was halted… They’re currently sitting in a container on the other side of the building.”

Hollywood director James Cameron was also part of the camera development team, and he too lobbied for a 3D camera. He proposed 3D movies of Mars, but the technical obstacles were too difficult to overcome.

Transmitting photos

When you’re transmitting photos from Mars, file size is a big point to consider. The Mars Rover uses a UHF transmitter to beam photos back to earth. The Rover beams information to two spacecraft orbiting Mars, which then relay information back to earth.

The Rover can only transmit just over 30mb back to earth each day. This would amount to just 30 photos at 2 megapixels, or just 6 seconds of HD video from a typical SLR. This 30mb limit also has to account for transmitting instrument data and telemetry though. Bandwidth is extremely limiting!

Panoramic Photos

The Mars Rover has already beamed back some stunning panoramic landscape photos of Mars. These photos are made up of 150 smaller photos, taken as the camera slowly rotates a full 360 degrees. The panoramic camera, known as a Pancam, consists of a large robotic arm on the top of the rover. It holds two cameras (one on the front and one on the back) and the whole module rotates and swings to capture a full panoramic view.

NASA has promised HD videos at 10 frames per second and plenty more visuals over the coming weeks. Of course, research and data is a their priority, but once the hard work is out of the way we’ll no doubt be treated to some stunning visuals from Mars!