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The camera is monochrome, another sensor gets "color" information. I think even the black and white images are not really "true" images since the sun is really

by runj__ 11y ago

The camera is monochrome, another sensor gets "color" information. I think even the black and white images are not really "true" images since the sun is really really really far away (not totally sure about that though). EDIT: LORRIs images are true, Pluto is actually pretty bright (the sun is amazing) and the camera is great (science is a amazing).

danielweber 11y ago
On Pluto, the Sun is 250x more bright than the moon is on Earth. And moonlight (at a full moon) is pretty sufficient for most things you do with your eyes. http://blogs.discovermagazine.com/badastronomy/2012/03/15/bafact-math-how-bright-is-the-sun-from-pluto/#.VabNGcZVhBc http://blogs.discovermagazine.com/badastronomy/2012/03/15/ba...
- Someone 11y ago
  That's because the human eye works across an amazing range of light intensities. https://en.m.wikipedia.org/wiki/Adaptation_(eye)#Efficiency https://en.m.wikipedia.org/wiki/Adaptation_(eye)#Efficiency: "The human eye can function from very dark to very bright levels of light; its sensing capabilities reach across nine orders of magnitude. This means that the brightest and the darkest light signal that the eye can sense are a factor of roughly 1,000,000,000 apart. However, in any given moment of time, the eye can only sense a contrast ratio of one thousand. What enables the wider reach is that the eye adapts its definition of what is black." Pluto is 30-50 AUs from the sun, so ignoring the effects of any atmosphere, there's "only" a factor of 900-2500 more sunlight on Earth than on Pluto (sun vs full moon is 400,000:1 or thereabouts)
Maultasche 11y ago
Yeah, I was surprised about how bright the sun is on Pluto. Before this week, I thought that it was pretty much just starlight on Pluto with the sun looking more like Venus at night. It turns out that the day on Pluto is like dusk on Earth. Check out this great page from NASA: it will tell you the time (for your location) where the daylight will be equivalent to the daylight on Pluto: http://solarsystem.nasa.gov/plutotime/ http://solarsystem.nasa.gov/plutotime/ You can also see photos other people have uploaded, giving an idea of what Pluto daylight looks like. Surprising bright. For me, it's something like 8:15pm when the daylight is equivalent to Pluto.
david-given 11y ago
It can't actually take 'true' colour pictures at all --- RALPH has sensors in blue, red, infrared and methane, but not green. I suspect they can probably synthesise true colour-ish by comparing the monochrome images to the blue and red ones; subtract blue and red from overall brightness, and what you have left is green (ish). Enormously technical nigh-incomprehensible paper here: http://www.boulder.swri.edu/pkb/ssr/ssr-ralph.pdf http://www.boulder.swri.edu/pkb/ssr/ssr-ralph.pdf

by runj__ 11y ago

danielweber 11y ago

On Pluto, the Sun is 250x more bright than the moon is on Earth. And moonlight (at a full moon) is pretty sufficient for most things you do with your eyes. http://blogs.discovermagazine.com/badastronomy/2012/03/15/bafact-math-how-bright-is-the-sun-from-pluto/#.VabNGcZVhBc http://blogs.discovermagazine.com/badastronomy/2012/03/15/ba...

Someone 11y ago
That's because the human eye works across an amazing range of light intensities. https://en.m.wikipedia.org/wiki/Adaptation_(eye)#Efficiency https://en.m.wikipedia.org/wiki/Adaptation_(eye)#Efficiency: "The human eye can function from very dark to very bright levels of light; its sensing capabilities reach across nine orders of magnitude. This means that the brightest and the darkest light signal that the eye can sense are a factor of roughly 1,000,000,000 apart. However, in any given moment of time, the eye can only sense a contrast ratio of one thousand. What enables the wider reach is that the eye adapts its definition of what is black." Pluto is 30-50 AUs from the sun, so ignoring the effects of any atmosphere, there's "only" a factor of 900-2500 more sunlight on Earth than on Pluto (sun vs full moon is 400,000:1 or thereabouts)

Maultasche 11y ago

Yeah, I was surprised about how bright the sun is on Pluto. Before this week, I thought that it was pretty much just starlight on Pluto with the sun looking more like Venus at night. It turns out that the day on Pluto is like dusk on Earth. Check out this great page from NASA: it will tell you the time (for your location) where the daylight will be equivalent to the daylight on Pluto: http://solarsystem.nasa.gov/plutotime/ http://solarsystem.nasa.gov/plutotime/ You can also see photos other people have uploaded, giving an idea of what Pluto daylight looks like. Surprising bright. For me, it's something like 8:15pm when the daylight is equivalent to Pluto.

david-given 11y ago

It can't actually take 'true' colour pictures at all --- RALPH has sensors in blue, red, infrared and methane, but not green. I suspect they can probably synthesise true colour-ish by comparing the monochrome images to the blue and red ones; subtract blue and red from overall brightness, and what you have left is green (ish). Enormously technical nigh-incomprehensible paper here: http://www.boulder.swri.edu/pkb/ssr/ssr-ralph.pdf http://www.boulder.swri.edu/pkb/ssr/ssr-ralph.pdf