James Cameron's 3D Vision For Mars

Wow - what a lazy and erroneous story. The 2007 scale-back didn't change the 3D camera capability, merely the "zoom". For the record, we've had 3D cameras on every Mars lander mission since Pathfinder (1997), so NASA beat Cameron by a mere 13 years :)

Awesome! Then we can have pictures like these:
http://www.rainbowsymphony.com/mars-3d-gallery.html

How about a 3D Electron Microscope to find LIFE if this is what we are looking for!

"Wow - what a lazy and erroneous story. The 2007 scale-back didn't change the 3D camera capability, merely the "zoom"."
The removal of the 15:1 zoom lenses (100 mm to 6.5 mm variable focal length) from the Mastcams meant that the two Mastcams that were built were made with two different fixed focal lengths. One Mastcam has a focal length of 100 mm while the other Mastcam has a focal length of 34 mm. Imagine trying to take 3D pictures/video with cameras of two different focal lengths and you will see the problem.

The decision to remove the zoom lenses was made back in 2007 and in my opinion is a great example of being penny wise and pound foolish. A rover costing over $2 billion dollars had a few million shaved off the cost by decreasing the capability of the most important part of the rover for public relations. Hopefully this reversal has not come to late since they now have less than a year to build the Mastcams with the zoom lenses.

"For the record, we've had 3D cameras on every Mars lander mission since Pathfinder (1997), so NASA beat Cameron by a mere 13 years"
Yes, if you mean black and white cameras but the Mastcams with zoom lenses (if they are finished in time) would be the first color cameras on Mars capable of 3D pictures/video.

LOL, yes it's not a new idea. However if Cameron's star power can influence why not give him some credit? We need more people with imagination in all fields to take interest in NASA missions. I for one would look forward to a big screen Cameron documentary in addition to the NASA supplied-only-on-the-internet pictures. Think outreach people, we need this positive attention and public buy-in.

"Yes, if you mean black and white cameras but the Mastcams with zoom lenses (if they are finished in time) would be the first color cameras on Mars capable of 3D pictures/video."

If you mean black and white?! Every single successful Mars lander to date, six of them so far, had color stereo cameras (Viking 1 and 2, Mars Pathfinder, MER A and B, and Phoenix).

"If you mean black and white?! Every single successful Mars lander to date, six of them so far, had color stereo cameras (Viking 1 and 2, Mars Pathfinder, MER A and B, and Phoenix)."
I believe that all of those missions used black and white cameras. They could approximate color by taking three pictures using a red, green, and blue color filter but they were black and white cameras. The MSSS website has a description on the fixed focal length Mastcams.

They could approximate color by taking three pictures using a red, green, and blue color filter but they were black and white cameras.

That is the way that all color cameras work. There are red, green, and blue filters somewhere in the color camera over sensors that detect light intensity, i.e. black and white. In fact, that's pretty much how your eyes work, with different pigments in the cones of your retina. Science cameras often have more than three filters, including some outside the visible, to get more detailed spectral information than the human eye can detect.

The bottom line is that you can see six Mars landing sites to date, all in beautiful stereo color. (Though the stereo from Viking can be difficult for some humans to appreciate, since those cameras were much further apart than our eyes are.) MSL will not have the first stereo color camera.

The MSL camera will hopefully be the first to take video at a reasonable frame rate. You can see low frame rate videos taken by MER of dust devils. Hopefully MSL will see some dust devils. There's not a lot else that moves on Mars to take video of.

"That is the way that all color cameras work. There are red, green, and blue filters somewhere in the color camera over sensors that detect light intensity, i.e. black and white."
The average color camera does not have to shift color filters over the entire CCD and take three pictures through red, green, and blue filters in order to generate a color picture. The MSSS website link in my previous comment mentions that the Mastcam cameras use a Bayer Pattern Filter CCD. One big advantage of that is that the MSL rover won't have to take and send back three pictures in order to get a color picture. The MSL rover is also capable of both lossless compression and JPEG compression on the color images it takes.

"The bottom line is that you can see six Mars landing sites to date, all in beautiful stereo color."
That is true but in the case of the MER rovers only a tiny percentage of the Pancam pictures are in color.

The average color camera does not have to shift color filters over the entire CCD and take three pictures through red, green, and blue filters in order to generate a color picture.

Indeed, the average camera mixes the color filters over a single CCD using the Bayer pattern, for cost. However top-end camcorders use three CCDs with separate filters which gives better images, avoiding anti-aliasing issues.

Many things on Earth move, so you must to be able to take the three images at the same time (either with one or three CCDs). Almost nothing on Mars moves, so it makes more sense to move filters over a single CCD and take the images in sequence. The MSL cameras in fact have moving filters over the cameras for narrower science spectra.

One big advantage of that is that the MSL rover won't have to take and send back three pictures in order to get a color picture.

That's not a big advantage. With the Bayer filter, the MSL cameras have effectively half-resolution green and two quarter-resolution red and blue images. The same data volume with the same (actually rather better) resolution is possible and routine with separate images by dialing the lossy compression level. MER of course also has lossy and lossless compression for images.

An advantage is that all MSL Mastcam images will be in color (though not all in natural color or tending towards a single color, when one of the non-neutral filters is in front). A disadvantage is that all MSL Mastcam images will be in color. There is not an option to get a high-resolution mono-chrome broadband image, which is better for some purposes. With a black and white camera and multiple filters, you get the best of both worlds. That is, on a world where things don't move.

What you don't get in that case is color video, which is of limited application on Mars. If video was considered to be a competitive advantage for the selection of the Mastcam, then that would have driven the choice of a Bayer filter over the CCD. Getting color images does not drive that choice.

A new thing for Mars is that the Mastcam Bayer filters have, I'm sure, been chosen to mimic human eye filters in order to get "natural" color. (I.e. matching the limitations of the human eye.) Usually science camera filters are made narrower for science purposes, but that brings up questions about what Mars "really" looks like. This camera will answer such questions.

"That's not a big advantage."
Well the MSSS website says it is an advantage since it reduces data volume for color pictures.

"With the Bayer filter, the MSL cameras have effectively half-resolution green and two quarter-resolution red and blue images."
There are four subpixels (one red, two green, one blue) for each pixel in a Bayer Pattern Filter CCD so it doesn't lower the resolution. In fact the resolution of the MSL Mastcams (1200x1200) is higher than the resolution of the MER Pancams (1024x1024).

"With a black and white camera and multiple filters, you get the best of both worlds."
Well NASA must think that there are more advantages by using color cameras with multiple filters. After all they are using Bayer Pattern Filter CCDs on the MSL for both the Mastcams and the MAHLI.

Well the MSSS website says it is an advantage since it reduces data volume for color pictures

Not if you compare apples and apples. Obviously yes, reduced resolution images will take up less data volume.

There are four subpixels ...

Subpixels. Right. Ok. This is simple -- each pixel has exactly one color filter over it. The exposed CCDs are 1200x1200, not 2400x2400. If you put two green, one red, and one blue filter over every single pixel, you end up with a black and white camera with a little bit of green bias.