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Mars images rendered in 4K [video]

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Re: Mars images rendered in 4K [video]

#101

what impressed me more about this video is how earth like an alien world looks like. it may not have vegetation but there's nothing I wouldn't expect to see somewhere on earth.

I believe the images are quite aggressively recolored and cleaned up. The narrator states that the original images would be reddish and hazy.

The cameras on the rovers are not the same as the camera on your phone or a DSLR. Each camera has specific sensors for different wavelengths of light [0]. The images are really just the wavelength reflection intensity measurements (think of it like RAW images on a DSLR but for more than just RGB).

The colorization is done by taking several of these images for wavelengths and adding them together. For example blue is in the 450–495 nm wavelength, green 495–570 nm, and red 625–740 nm. The Mastcam on the curiosity rover is actually two cameras with various sensors for different wavelengths (including wavelengths outside the visual range). They can use these images to create color images. You take the 440 nm sensor and give each pixel a value between 0-255 and display that with more/less blue. Take the 525 nm or 550 nm sensor and make them green and the 675 nm sensor and make them red. When you combine these you get an image that looks pretty similar to what it would look if you were really there (It's called true color and false color [1]). This same process is used by satellites as well to measure and classify things on Earth from space. They way different surfaces reflect light in different wavelengths help scientists classify things on Earth and Mars and all over the solar system. (It's Okay to Be Smart on YouTube has a cool video about Infrared [2])

[0] https://mars.nasa.gov/msl/spacecraft/instruments/mastcam/for...

[1] https://en.wikipedia.org/wiki/False_color

[2] https://www.youtube.com/watch?v=srzniA8EKDk

Re: Mars images rendered in 4K [video]

#103
post #70

Earlier quoted context omitted.

Mars is constantly moving. There are wind storms, dust devils, ice melting, all kinds of things. Here's a dust devil https://www.youtube.com/watch?v=k8lfJ0c7WQ8 (again, it's still images to make a video) but not because "nothing ever moves on Mars"! Mars is constantly shifting and changing with its weather and seasons. Ice caps freeze more, and ice caps melt more, water or other liquid flows down hills when it gets w…

Earlier this year I made a video[0] where I took two images which are frequently posted on reddit that show the movement of martian sand over a day and interpolated (with python and opencv) the movement into a smooth video. I'm currently working on restoring some Apollo footage, but one of the pending projects is taking the Curiosity descent sequence (at 4 frames per second) and give it a shot at some nice quality, X…

>give it a shot at some nice quality, XXI century interpolation

I think it has been done? https://www.youtube.com/watch?v=tMntZ6_R78Q

Re: Mars images rendered in 4K [video]

#104

Interesting facts that I didn't know before seeing this video: - The opportunity rover captured a barren scene which was named Rub Al Khali (Yes! On Mars!), named after the Rub Al Khali desert area which touches UAE, Saudi, Oman and Yemen. (1) (2) - The video says that Mars rovers send back images (not videos) and then those images are stitched together to create videos, because "nothing ever moves on Mars". But I wo…

> named after the Rub Al Khali desert area

> named after Namib desert in Africa

In a few hundred years, maybe these won't be deserts anymore. It will make for an interesting fact!

Re: Mars images rendered in 4K [video]

#105
post #10

The narrator explains why getting HD video would be impractical, but I disagree that we get the same experience from panning stills. imagine seeing the swirling dust, shifting sands, the bumps and parallax from a moving rover. that would be so cool!

> The narrator

It's a machine.

Re: Mars images rendered in 4K [video]

#106

Earlier quoted context omitted.

There are "dust devils" on Mars: http://www.esa.int/ESA_Multimedia/Images/2018/04/Dust_devil_... .

You just linked to the ESA version of my NASA link :)

I think I meant to reply to the person above you.

Re: Mars images rendered in 4K [video]

#107
post #7
post #2

In my youtube quality menu, it only goes up to 1080p. Is this really 4K?

I downloaded it with youtube-dl because I cannot stand the excessive adverts on Youtube these days. During the download it grabbed this video file: Input #0, matroska,webm, from 'New - Mars In 4K-ZEyAs3NWH4A.f313.webm.part': Metadata: encoder : google/video-file Duration: 00:10:08.41, start: 0.000000, bitrate: 4436 kb/s Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv, bt709), 3840x2160, SAR 1:1 DAR 16:9, 29.97 f…

> I downloaded it with youtube-dl because I cannot stand the excessive adverts on Youtube these days.

Can't you use an ad-blocker?

Re: Mars images rendered in 4K [video]

#108
post #52

Earlier quoted context omitted.

Very little shifting sands. Winds in Mars have almost no strength. Air pressure in the Mars surface is very low, something like 1% of Earths. Dust devils and storms are made of extremely fine powder.

The movement shown in this video[0] happened over the span of a martian day. Do not dismiss the winds of Mars, as they have also killed[1] a couple of rovers already. [0] https://youtu.be/k7pfdFMVj-o [1] They have also breathed new life on one of those (before killing it, yes) by cleaning the solar panels. I'm referring to the MER Rovers Spirit & Opportunity.

As you said, that movement of was over a day and the camera was pointing downwards towards very tiny details of fine grained powder next to a wheel. You wouldn't notice anything in real time video.

The problem with Mars dust is that it's electrostatic and sticks to surfaces like solar panels.

https://www.nasa.gov/feature/goddard/the-fact-and-fiction-of...

>It is unlikely that even these dust storms could strand an astronaut on Mars, however. Even the wind in the largest dust storms likely could not tip or rip apart major mechanical equipment. The winds in the strongest Martian storms top out at about 60 miles per hour, less than half the speed of some hurricane-force winds on Earth.

>Focusing on wind speed may be a little misleading, as well. The atmosphere on Mars is about 1 percent as dense as Earth’s atmosphere. That means to fly a kite on Mars, the wind would need to blow much faster than on Earth to get the kite in the air.

Re: Mars images rendered in 4K [video]

#110
post #7

Earlier quoted context omitted.

I downloaded it with youtube-dl because I cannot stand the excessive adverts on Youtube these days. During the download it grabbed this video file: Input #0, matroska,webm, from 'New - Mars In 4K-ZEyAs3NWH4A.f313.webm.part': Metadata: encoder : google/video-file Duration: 00:10:08.41, start: 0.000000, bitrate: 4436 kb/s Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv, bt709), 3840x2160, SAR 1:1 DAR 16:9, 29.97 f…

> I downloaded it with youtube-dl because I cannot stand the excessive adverts on Youtube these days. Can't you use an ad-blocker?

Or, you know, pay for the premium version
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