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Why do we not add an everyday (with some modifications for protection obviously) digital camera to spacecraft so that we can get a (semi) truecolor image of what they are seeing?

I was reading about how with the Mars rovers, it is really just scientific estimations of what the true color really is (that humans would see) Why not just implement a standard digital camera to see this?

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    $\begingroup$ You will hear lazy rocket scientists make up excuses about added complexity, failure risks, extensive testing procedures, radio interference, power consumption, communication limits, budgets. And astronomers who are very picky with instrument quality. Tiangong-2 was filmed by a separate satellite camera. Hayabusa-2 will use a sat cam to film the explosives making a crater. The Space Society has long lobbied for a microphone on Mars and the 2020 rover will have one. And Juno has a "non-scientific" camera. So it is coming. $\endgroup$
    – LocalFluff
    Commented Nov 4, 2016 at 8:01
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    $\begingroup$ The science instruments on the Mars rovers and other science spacecrafts measure the wavelengths of light (i.e. colors) very exactly. If you heard that the color is an estimate, I suspect it is so only for photoshopped images meant to look pretty for publishing. Our minds change colors alot to make the same object look the same, mostly from our memory, regardless of light settings. What the "true color" is, is really a deep philosophical conundrum. And btw have a look at NASA's Phonesat project. $\endgroup$
    – LocalFluff
    Commented Nov 4, 2016 at 8:21
  • $\begingroup$ The issue is more complex than just the camera hardware. Because Mars' atmosphere is different to Earth's, the same object will look different on Mars' surface than it does here on Earth. That makes it difficult to decide what is true color. $\endgroup$
    – Hobbes
    Commented Nov 4, 2016 at 8:57
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    $\begingroup$ I object to the phrase "make up excuses". Added complexity, failure risks, extensive testing procedures, radio interference, power consumption, communication limits, budgets are all valid points. You don't want the \$500 camera to interfere with the \$100 million mission. $\endgroup$
    – Hobbes
    Commented Nov 4, 2016 at 12:36
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    $\begingroup$ @Innovine Forget about different cameras. I shoot RAW, which moves processing steps like demosaicing, whitebalance and so on out of the camera and into the post-processing stage. The same RAW file can produce hugely different resulting images, and there's nothing saying that one of them is more "correct" than the other, other than -- you guessed it -- subjective perception. $\endgroup$
    – user
    Commented Nov 8, 2016 at 12:33

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"With some modifications" for space environment is a time and money-intensive activity, at least if you want it to work. You'd need some serious justification for such a camera on a mission that is already highly cost-constrained.

There is always a color camera on a Mars rover anyway, usually with much more than three color filters, so its color vision is better than ours. The filters don't line up exactly with our three, each being much narrower for science reasons. But by combining images from filters you can get a very good approximation to how it would look to us.

Which gets us to how it would look to us. That requires some analysis and adjustment as well, due to the very different direct and scattered light at Mars, both in wavelength distribution and intensity. Even at Earth these differences make whether a digital image "looks like it would to us" a very subjective matter. Do a little reading on white balance and color temperature to see how really tricky it is on Earth to get a picture to look "realistic".

Yes, we could fly commercial cameras if we wanted to. But even if they work, they don't automatically solve the "truecolor" problem you have posed. In fact it would be much more difficult to solve that problem with the data you can get out of a commercial camera, as compared to the data we get from our science cameras.

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Deep space probes have tight mass, power, and bandwidth budgets. Imaging must serve the needs of the mission, and more often than not those needs have nothing to do with what something looks like to the naked eye. Think about the bandwith limits on the New Horizons spacecraft (roughly 1 kbit/s at Pluto).

True-color imagery would be great PR, but it would come at too high a cost.

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