Russian Satellite Takes Most Detailed 121-Megapixel Image of Earth Yet 123
Diggester writes "The satellite, known as Elektro-L No.1, took an image from its stationary point over 35,000 kilometers above the Indian Ocean. This is the most detailed image of the Earth yet available, capturing the Earth in a single shot with 121-megapixels. NASA satellites use a collection of pictures from multiple flybys stitched together. The detail in the pic is just amazing."
Why all this rust-orange? (Score:4, Informative)
Also, I looked at the zoomable image and zoomed in all the way in and.... saw mostly macroblocks? Is that still "amazing detail" in a sense that eludes me?
what's the availability/licensing? (Score:5, Informative)
One reason the NASA global-coverage image sets that were released in 2002 (with updates starting in 2005) have become the de-facto standard source is that: 1) anyone can download them; and 2) they're in the public domain, so anyone can use them for any purpose. You can get a bunch of versions here [nasa.gov] and from the Visible Earth site linked at the bottom of that page.
This one looks cool, but further use will be limited if the only thing I can do with it is look at it in this online zooming browser.
Re:Looks Photoshopped (Score:5, Informative)
It looks photoshopped because it includes false color data from an infrared cam. It's not photoshopped.
Re:what's the availability/licensing? (Score:4, Informative)
Re:why do Russian and US colors vary so much? (Score:4, Informative)
The "Blue Marble" image you're pointing at is based on EOS (Terra/Aqua) imagery. The most recent NASA Blue Marble (Blue Marble 2012 [nasa.gov]) is a composite based on the new NPP Suomi spacecraft, with approximately a 1-km pixel resolution.
As to "accurate"... I think the Blue Marble images (based on the visible-light band sensors of their respective spacecraft) are closer to what a naked eye in orbit would perceive than the Russian imagery, which seems to include false-color infrared. But "naked eye in orbit" is scientifically less useful than the multi-spectral IR and visible all of these spacecraft can sense.
Re:Sweet! (Score:5, Informative)
I specified that based on visual acuity limits. There's a lot of optical theory explaining why over 300 dpi is mostly useless for toner on paper. Unless your eyeball lens diameter is 10 times bigger than the average human or your retina cell layout is different than all known humans, it is not optically possible to resolve 3000 dpi or whatever on paper under normal conditions and lighting. Depending on how close you can hold the paper before you can't focus on it anymore, and tangentially depending on how bright the light it (little pinhole camera iris) humans top out around 300 dpi.
Now, projected thru transparencies onto a overhead, higher res works, if you have old fashioned overhead projectors and sit close to the screen. Also there are ugly aliasing and anti-aliasing effects that can be avoided by higher res with real vector scaling. And high res allows better/smoother color mixing, in that bluring together 2**8 pixels of 2**16 color is the same as one 2**24 pixel, more or less. There are also relative brightness/consistency effects where making a "line" that varies from 8 to 9 pixels wide looks a lot less consistent than a line that is 85 or 86 pixels wide at 10 times the res, look at the percentage variation of one pixel. If the lighting is really bad, there are strange shadow effects where you can perceive over 300 dpi if the shadows land just right. Also there are some strange toner based textural issues where the plastic surface of thinner lines literally looks different. And some 3-d effects of toner on paper. So over 300 dpi is not a complete waste of time, just mostly a waste with average pictures under average conditions. It would be extremely hard to justify over 1200 dpi even in the weirdest corner cases.
Re:Wait, what? (Score:4, Informative)
The rust is annoying though... Because they're compressing 4 wavelengths into 3 wavelengths. An image with only the RGB would look nicer. They could store the 4th IR channel as alpha channel...
No matter which way you "look" at something you are either compressing or ignoring some quality of light. The "art" of astrophotography is therefore about how much information you intend to leave out and how much you squeeze into the narrow bands of light we humans can perceive. If you are not happy with the rendering, you might be able to source the uncompressed scientific data -- which will still only ever contain partial-information due to optical, CCD and other limitations -- and render it yourself [spacetelescope.org]... Assuming Roskosmos make their equivalent of FITS data available to the public like NASA does.