4/20/2013

Pale Blue Dot: ethical considerations on the "restoration" of a classic image

"Pale Blue Dot" in original size and color.


On February 14, 1990, having completed its primary mission, the Voyager 1 spacecraft was commanded by NASA to turn around and photograph the planets of the solar system. NASA compiled the 60 images of this unique event in a series called "Family Portrait".

One of the pictures returned was of Earth, from a record distance of about 6 billion kilometers (3.7 billion miles), showing up as a pale blue dot in the grainy photograph you see above; this picture would be later known as "Pale Blue Dot". Yes, that tiny blue dot on the right is really the Earth.

"Pale Blue Dot" is also a book inspired by this picture, written in 1994 by Carl Sagan, where he describes the image in these words :
«From this distant vantage point, the Earth might not seem of any particular interest. But for us, it's different. Consider again that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.»
A mote of dust suspended in a sunbeam. A wonderful picture that brings another perspective on Life, the Universe, and Everything.

A wonderful picture, of course, but of poor quality. Its original size is 600 × 442 pixels, which is infinitesimal when compared to the multi-megapixel capacities of our most rudimentary contemporary appliances. But we must ponder upon the 6 billion kilometers traveled at the speed of light by each of these pixels to better appreciate the feat that represents the image, no matter how small it is.

And even if the photograph was taken with the darkest filter and the shortest possible exposure (5 milliseconds) to avoid saturating the camera's vidicon tube with sunlight, the result is grainy and overexposed.

This is ruminating on the technical limitations of the era that came to me the idea of ​​trying to solve this problem. It would be relatively easy to improve the sharpness, resolution and brightness of the image with my trusty Photoshop to make, for example, a large poster or wallpaper. But just how far can we modify or alter a historical picture like this without betraying its very essence, its authenticity, its substance-full marrow?

The vast majority of astronomical images provided by various space agencies to the media are manipulated prior to being published. A little more contrast here, a little less light there, and reframe... Some of them are transmitted in shades of gray by satellites to be colored later by specialists, and others are completely recolored to highlight some phenomenon. In short, unless you browse through the space agencies' archives providing access to raw images taken by the various ongoing missions, most of us will rarely see an astronomical image that wasn't "improved" first.

Only there's this small thing. "Pale Blue Dot", the image you see above, has never been altered. What you see is exactly what the Voyager spacecraft sent us, pixel for pixel. It may be of poor quality, but this defect gives it extra power. Because one of the grains of this diffraction effect, the one slightly lighter than the others, is our planet.

So I was well aware that any attempt to restore or improve the image would be futile because the real beauty of this picture, its deeper meaning lies in its initial imperfection. But as I was curious to see the result, I tried some experiments while trying to minimize the number of changes in order to stay as close as possible to the original. After several attempts and a few hours of handling layers, transparency, filters and all, this picture appeared.

"Pale Blue Dot", "improved" version.

No pixel was removed or added. Everything that is in this picture was on the original, the only compromise I had to make was to apply a Gaussian blur filter on the rays in the background to eliminate graininess, which also reduced the sharpness of the light rays. But as these are artifacts are caused by the lenses, I felt it was better to keep their beautiful prismatic colors than emphasize their exact shape, which is arbitrary.

The image was also greatly enlarged (more than 2500 pixels in height), which offers the possibility of making a printed large-format poster without aliasing, or a high-resolution wallpaper.

I like the final result, which is technically superior to the original, but I still have some doubts... "Pale Blue Dot" is a unique, historic image. It is the Mona Lisa of astronomical photographs. Can we really change it, no matter how slightly, without thinking about the ethical implications of such an act of treason and risk suffering the wrath of purists who will not fail to be offended? Maybe not, after all. What do you think?

But if you'd like to use it as a wallpaper, feel free to use this cropped and resized version.

"Pale Blue Dot", wallpaper format (1900 × 1200).

Because it is sometimes better to admire the splendor offered by the Universe, and leave aside the ethical considerations.

1 comment:

  1. Thank you for your efforts in making this version of the image. I am very glad you stopped and pondered the implications of editing this most special of images. Of course there is always the desire to be able to see this image in a form that works in our modern technology, much like restoring a degraded film.

    You did a great job and didn't push it to what I would consider detrimental to the original. I am wondering, do you have your full size version available anywhere for download? I'd love to get a poster printed if you don't mind sharing it.

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