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How Spirit Takes Pictures
Some Clown writes "MSNBC has a great article on the details of the camera system on the Mars Rover titled How Sprit makes great photos. Apparently the high resolution images are all done with a 1-megapixel camera. All the money is in the CCD and Lens. The hardcore digital photographers in the crowd will probably find the article to be only a teaser on the technical specs, but the rest of us in the unwashed masses should find it interesting."
The hardcore digital photographers in the crowd will probably find the article to be only a teaser on the technical specs, but the rest of us in the unwashed masses should find it interesting.
What does having a six-digit Slashdot UID have to do with digital photography knowledge?
You probably shouldn't click this.
Why not link directly to the original article?
The unofficial
It is also interesting to see how it produces color photos. Instead of using a 3 color sensor, it uses a B&W camera with 3 colour filters that recombine into a colour image. This is calibrated by a colour wheel on the rover itself.
Neat stuff
Somehow I don't see the phrase "shake it like a 1-megapixel digital camera" being as catchy
High quality images are good for PR, but what I really want to know is how it extracts information from the environment, how this information is being used, and whether or not we found anything we didn't expect to find.
~To choose doubt as a philosophy of life is akin to choosing immobility as a means of transportation. -Yann Martel
I am not trying to be negative, I think what they are doing is great and long overdue. Can't wait till we have Rovers on other planets. But why did it cost $400 million? I've read about what Rover is and how it was built and what it does. I am sure it was expensive to build but $400 million? Does that include the cost of getting it there?
I dunno, That would suck if all Spirit's pictures had a finger in the bottom corner of them like all mine do.
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Humans to the moon (1969)
Digital cameras to mars (2004)
Internet Fridges to pluto (2010)?
Is this progress?
It is interesting, but I suppose it is explained because this sort of tech has to be (physically) tested a couple+ years in advance (and 2 years is in the final test/construction phase already, initial planning was years before), so strapping the latest untested camera in to a planned and tested system would potentially introduce a weak point in the system. Yeah, pretty nifty, kinda shows the potential 'old' hardware has when used to its full potential.
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FreeNET user? Comfortable with the adverse selection?
It's important to note that in a color digicam each "pixel" only senses 1 color. The NASA cam is a black and white, and to make color they take 3 shots with different filters. This makes it equivalent to a consumer 3MP camera.
They also have a nice lens and a large sensor which helps as well.
Tim
Resolution in cameras (both digital and film) is really determined by optics. By taking pictures of a smaller area and stitching them together, they can probably get better pics than most pros get with their high end Digital SLRs, because they've put more money into the optics than the sensor. Also, the higher density CCDs and CMOS sensors going into digital cameras now tend to be more prone to noise than some of the very high quality, lower density models.
Also, remember that the cameras in the rover had to go through a lot more testing than a typical consumer camera, so it's probably using three, four, or even five year old components in the imaging systems.
It's good to use your head, but not as a battering ram.
No, I read it; obviously the sensors in my little 1MP cam won't be anything near what's in the pancam, but I can do something about the lens. Grab an eye doc friend who can get some decent prescription-ground lenses and go for the stereo effect. I'm not sure; one might have to write a small program to make it work, but it could be fun to see the results.
The NASA guys had to start somewhere. Their biggest advantage will be the sensors, but there's no reason we can't replicate the rest. If one wanted to go all-out, it might even be feasable to use an array from a high-mp camera and configure it to use multiple sensors to produce 1px.
Damon,
http://actionPlant.com
Actually, it's only 1 megapixel because it's a cameraphone. Sprint donated the phone in exchange for showing off their new Martian-wide network. The lander just waits until 7pm so it can send home pictures using free nights and weekends. Unfortunately the budget killer is the shots from the rover since they incur roaming charges.
"Sorry, your browser is not compatible with this feature!"
@%**! MSnbc
Click on the "Interactive feature" if you don't know what I mean,
then curse microsoft,
then go straight to http://marsrovers.jpl.nasa.gov to see the images without paying the microsoft tax. I vowed a long time ago to stop clicking on msnbc links.... sucker that I am to keep coming back for more...
Nasa uses a 1MP camera but 3 filters. The 3 filters are combined to give you a color image.
Consumer 1MP have the same number of pixles buy each pixle has only 1 filter. The image is then interpolated to get a true color image.
Even if your optics and ccd were the same quality as Nasa's you would still only have 1/3 the resolution.
"NASA's Spirit Rover is providing a lesson to aspiring digital photographers: Spend your money on the lens, not the pixels."
Every good photographer will tell you the same. It still amazes me that people are willing to drop Can$.5k for a digital camera, but think you are nuts for spending the same money in a lens.
Too bad the digital cameras all come with Zooms. At the same price, a zoom lens will tend to be worse than a fixed lens. An old camera, the yashica t4 super won a great reputation for its superb fixed lens (35 mm Carl Zeiss).
I have one, and I love it. It takes the best pics I have ever seen in a P&S.
Here's a story about some of the software involved.
Brady
I'd imagine it's more to do with radiation hardening, they could have, for a paltry sum, put a top-of the range con/prosumer camera up there and if it broke, no big deal, but it wouldn't survive outside the protection of Earth's atmosphere, the smaller alectronics would be fried by radiation from the sun in no time. Radiation hardening is great, but a difficult, complicated, "fiddly" procedure, so basically all the tech on the shuttles are a lot less advanced than the stuff we take for granted here on Earth. They wouldn't survive space if they weren't.
I am not very surprised that no journalist understand that, I am more surprised that /. readers missed the point: it is simply nonsense to say that the camera is 1M pixels.
/. readers, please, if you are geeks, always read the small lines. Do not expect NASA or a journalist to do that for you. It is not the interest of the former, and the latter is just stupid.
Indeed, the CCD has 1 million pixels, but look at the published pictures: they are assembled from a great number of small 1 megapixels squares!! Simply have a look at the raw pictures on marsrovers.jpl.nasa.gov: some of them are not fully transmitted yet, consequently parts of the pictures are black.
To make a "normal" picture, like one you would naturally do with your 5M pixels camera, the pancam needs to take shots from, say, 20 different angles. And it is even worse than that: each pictures must be taken 4 times with each filters to get colors. Do not even dream of taking photographs of moving subjects!
There is another drawback: there is two cameras, for stereo. But if you look at the tech specifications on Cornell website, you'll see that each camera has filters that can cover only one half of the color spectrum. Hence, to get color pictures, you have to combine the photographs taken by both the left and right cameras. That's why there is some weird colored patterns on big objects: to put it simply, the left camera sees the red, the right one sees the blue! But both cameras do not see exactly the same thing!
And nonetheless, there was a hint: do you really expect 1M pixels raw pictures to weight 7MB? Huuh?
"Perhaps I'll dust my old 1MP camera off and see if I can do anything similar."
You're going to send your old Sony Mavica to Mars?!?!?!?!?!
A lot of people see the prints from my digital SLR, a gracefully aging Nikon D1h and are astonished to learn it's from digital. Most then refuse to believe it's only a 2.7mp camera.
Near all my pictures at www.gavincato.com in the photography section are with the Nikon D1h.
The Nikon D1h has only a 2.7mp sensor, but the output is fantastic. The pixels are large, and the noise is pretty low. It's pretty much noiseless until you hit 800 ISO, and even at 1600 ISO it's significantly better than 1600 speed film.
NASA is very correct in saying the lens & sensor are important, for example most of my lenses are ludicrously expensive (often more than the camera body) and the majority of them are fixed length lenses and thus have incredible optics.
I've previously owned a Nikon D100 which had 6mp, but I found to my surprise that I preferred the output & prints from the D1h. I originally bought the D1h to complement the D100 (the D1h is a crazy fast camera designed for sports), not replace it, but after a while I ended up selling the D100.
The guys in the Canon camp have said the same thing, they much prefer the output of the 4mp Canon 1D vs the 6mp Canon 10D.
They mentioned that the design process of the Huble's CCDs at a resolution of 800 x 800 contributed to the current mass production of consumer CCD cameras, so I don't think they are afraid of pushing the envelope if it is needed to meet mission requirements.
question. is your 1d full frame? that would easily explain why it's got better iamges than the 100d.
i'm one of those int he canon camp and i do have to concur with you on those findings. my canon has an APS sized sensor and can take very noise free iamges upto 400 ISO, at 800, it's still useable.. and i've done 1600 ISO shots, but i only use it if i have no other choice.
one thing people don't understand is the extra MPs only matter if you want to blow up your images. most people rarely print bigger than 4x6" and at the largest 8x10" 3MP resolution is more than good enough for an 8x10" print. after that, you want the best out of those MPs... NOT more MPs.
I believe sex is highly over rated... unless it involves me
If you follow that link and see the forbidden image of a Zero-Point Energy module left behind when the Grays dumped Elvis' worn-out second body on Mars back in 1972, you're just asking to disappear one of these days.
His name was Sergei Mikhailovich Prokudin-Gorskii, and they're awesome. You have to remind yourself of the time period when you see them, or you'll instinctively think they're more modern:
http://www.ummagurau.com/art/russia/
I don't know which is more depressing, that 2/3 didn't care enough to vote, or that 1/2 of those that did are crazy.
For those not familiar with it, the multiple exposure they talk about in the article has been long used in the darkroom and can be done easily with modern scanners with good software. It brings out extreme details in parts of images that are normally burnt out.
Take a single slide that you scan. With a program like VueScan, you can set the exposure of the scanner, so you can do a dark scan (thus exposing properly the light part of the image), a normal scan and a light scan (exposing the dark part of the image).
Import all 3 into a graphic program, superimpose them and cancel the parts that you don't like (which is the creative part and not as easy as it seems).
Note that you can also do that taking 3 pictures with various exposure with the camera on a tripod, and it's the way the Mars rover does it.
Non-Linux Penguins ?
huh? To get stereo, you need separation. You could do this with a couple of prisms, or maybe the biggest fresnel lens you ever saw, but why not just move the camera sideways between shots?
If your camera can take several pix in a row, use that, and simply move the camera laterally during the shooting (assumes you have fast shutter time).
Lastly, no. As I understand it, a CMOS sensor cut into 1000x1000 pixels will give you "better" pixels than the same die at 2000x2000 pixels, and coupling the pixels 2x2. This has several causes:
1) you can only average your combined pixels after sampling: thus you get quantisation noise (and hypothetically phase interferernce, although I've never heard anyone comment on this)
2) if you couple 2x2 pixels, you will get 1xR + 2xG + 1B pixels. Most pixels will be predominantly one of these colors, removing the other 3(2 for G) from the picture. This also means that a blue photon heading towards the 2x2 metapixel must hit the 1/4 area which can see it, else it is lost.
3) (I don't quite get this one. As close as I understand it:) The size of the sensor feature size is coming close to the wavelength of light: Sony's new 8mp sensor is 0.008 m long, with 3000 pixels. That makes each pixel 2.6e-6 m. Compare with Red light, at a wavelength of 0.7e-7 m. Each sensor is three wavelengths wide(!). This apparently means that you can't usefully use an fstop higher than 11ish on the new sony f828. Search photo.net for a technical discussion.
4) I guess that we also get effects from the fact that each pixel sensor is basically in a well, and the smaller the pixel becomes, the harder it becomes for a photon to hit the sensor, rather than the well wall. I never hear this discussed either