First color photographs of Mercury released by NASA | Hacker News Reader

First color photographs of Mercury released by NASA

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Link to the actual image: http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/EW020...

That seems to be the black and white one released yesterday and not the colorized version released today.

Color: http://messenger.jhuapl.edu/gallery/sciencePhotos/pics/first...

Thanks. Is it just me, or are there lots of artifacts in the color version that aren't present in the black & white one?

It's just you.

Don't be snarky.

There's definitely horizontal/vertical artifacts, probably from raw pixel interpolation. They're just more noticeable in the color image because the patterns are offset so they cause hue variances: http://fstutoring.com/~chris/temp/artifacts.png

What do you mean by 'raw pixel interpolation'?

Digital imaging devices have interesting pixel patterns. A common pattern found in digital cameras is four sensors in a square grid, red/green/blue/green. Since most image formats, like PNG, assume only three channels centered on one another, the four raw pixels must be interpolated to create one "cooked" pixel.

Due to reasons relating to signal processing which I'm not qualified to discuss (e.g. Nyquist limit and aliasing), a naïve sampling of these pixels can result in image artifacts such as Moiré patterns. My guess is that the artifacts I'm seeing in these images are of this type, but I could be wrong.

Oh you mean interpolating the Bayer filter, okay.

I work in this industry (digital imaging, not space) but since all color-filtered images I get to see are raw, I only see checkerboard grayscale :-)

The really, really small crater hits on Mercury are really awesome looking. It's like not even a single, minuscule grain of dust slamming into it was missed. I wonder now if our moon has numerous, tiny craters or mostly just large ones

http://jersus.com/wp-content/uploads/2011/03/moon-craters.pn...

What's the feature left of Debussy? About half-way between Debussy and the left of the image? Looks a little different to the other craters. Maybe more recent, and struck at more of an angle?

That's Matabei. I think the theory is that the mineral composition of the area was different, so it's covered in black dust instead of the bright material of Debussy.

Great, thanks!

For anyone else, he's a picture of Matabei:

http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?...

And a more detailed one from Wikipedia:

http://en.wikipedia.org/wiki/File:Matabei_crater.png

verdict: looks like our moon! but much hotter I imagine

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