Keep in mind that you're looking at obscenely enhanced detail. The "rotation" in my hypothesis was produced when the hardcopy was rescanned and not perfectly aligned on the scanner bed. Far from a digital watermark, I think you're looking at "print" noise that has been picked up by the scanner. The detail would not be visible to the naked eye, but it may be enough to cause the scanner to waffle between two of its discrete perception levels.

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Wow, you've pieced together a lot more detail on the processing than I could come up with.

One question: what is a raster?

When you say "correct", I assume you mean something like "preserving the orientation of the original image on the film".


Yes, under extreme stretch the background shows green. The green appears localized to the new background, not the black that remains inside the ellipse. This suggests it has something to do with the background that was selected, perhaps being enhanced by the later scanning?

The term "raster" comes from the television world and refers to the encoding of pictures in scan lines -- horizontal strips of varying color. That migrates to the digital imaging world where it refers simply to the grid of pixels. There are lots of esoteric sampling and filtration issues associated with the idea of a raster, but none of them is really important here. By "parallel to the raster" I simply mean that features in this photograph that would normally be expected to line up with the pixel grid, do not.

When you drag a rectangle or an ellipse in a paint program, it's always aligned with the pixel grid on the screen -- so many pixels wide and so many tall. It's extremely uncommon for a selection to be ever so slightly misaligned like that, so that corners of the rectangle lie in different rows or columns than their neighbors. That's what's happening here. The axis of the ellipse is aligned with the other imperfections, which lie at a subtle slant. That's what motivates us to hypothesize that this photo was digitized twice from successive hard copies.

By "correct orientation" I mean that the photo is presented the way the photographer framed it. Obviously in space up and down have little meaning and so photographs like this have no enforceable right or wrong orientation. But in this case attempting to track the changes in orientation of the photo help us understand all the changes that were made to it.

A digital photo remains in its initial orientation until someone changes it using software. While that is a simple operation, it is nevertheless harder than reorienting a physical photo, which requires simply turning it in your hand. If you are presented with a hardcopy of this photo, and you had no understanding of the original orientation, I believe you would naturally orient it so that the terminator was vertical. And I believe this is how the intermediate hard copy was placed on the scanner to produce the most recent digital image.

The scanner picked up the very subtle differences in the hardcopy created by the printing process and by the efforts of previous people to prepare the image for PR purposes. It also very slightly misaligned those features, as is common to the digitization of hardcopy on flatbed scanners.

I see no feature in this photograph that cannot be plausibly explained by processes known to be used in laboratories or offices where images are routinely handled. I see no hypothesized operation here that cannot be explained by PR-type tasks already seen to have been applied to Apollo and other space images by NASA PR people (e.g., removal of noise or aesthetically offending artifacts). I find this photograph in a context suggesting it is primarily for public relations use and not for scientific investigation.

The photo is mildly interesting, but otherwise unremarkable.

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After just changing four light bulbs in a day, I saw this article, and realized that some were done better in the past.

Bulbs that are left on will last a lot longer than ones that are turned on and off because the latter treatment is more stressful.

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Yeah, nothing stresses me out more than being tur....wait a second. THAT's not appropriate at all!

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"I'm making wheatloaf. It's like meatloaf, only with wheat"
"Isn't that just...bread?"

Then one day someone had forgotten to pay the electricity bill and...POP! Hopefully it will be a full Moon that night.

BTW, I think the electric company in that area should get some kind of recognition for dependable service! 8)

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If you go back to the NSSDC link and redownload the TIFF file, you will find it no longer has the odd mask. OH MY, they've caught on and are covering their tracks!

Actually, no. I emailed the contacts for the NSSDC page and asked about the history of that picture. I was curious if anyone could confirm some of Jay's comments about the generation of that image. Well, I didn't get the answers I wanted, however I did get this response:

I note that the new file is still oriented with the terminator vertical, and stretching the new image with the same contrast enhance shows blue instead of green, no oval mask, but still scan line patterns.

Thanks Irishman...mystery solved. 6 to 8 years ago would probably mean that image was processed with a now very out-of-date version of Photoshop and explains the "crudeness" of the technique. Time flies.

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Good job, everyone. Amazing what a little persistence, some knowledge, and asking a few questions can uncover.

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Clavius Moon Base