DIY galaxy photos: beauty and truth in data

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This stunning photo was taken not by the Hubble space telescope, but by some guy (Rogelio Andreo) out in the desert. Sure, he needed several thousand dollars in digital camera equipment to do it, but still - that's well within the reach of many hobbyists. Are we seeing a surge in amateur earthbound astronomy photography?

Read this Wired article to find out all about Andreo's process. If you happened to read my earlier post about data and scientific visualization ("You want raw data? You can't handle raw data") you know that I think filtering and processing data is an inevitable part of both art and science. Of course, different people have different opinions on the appropriate levels of filtration and processing. I liked what the Wired article had to say about it:

So, we live in a golden age for space photos, but looking at the technicolor images of what appears to the naked eye to be a fairly bland sky, we find ourselves asking: Does it really look like that?

As we find in this behind-the-scenes look at the making of a mind-blowing space photo, the answer is yes -- but just not to your eyes, which are pretty poor sensors, compared with purpose-built astrophotographic equipment.

But that doesn't mean the photos aren't "real." Most astrophotographers have an ethic: They won't add color or lasso just a part of an image for editing. They can only bring things out of the data, not add them. The photos are often processed in Photoshop, but what they do is the opposite of falsifying the visual record. Astrophotographers are using digital-editing tools to find the truth in the noisy data that are the heavens. (source)

Truth? Maybe. Andreo's process seems to come down more on the artistic side than the scientific side - he makes his processing choices based on aesthetics, not fidelity to the data or accuracy in conveying the data to a viewer. Still, it's a beautiful photo.

More like this

Thats not a galaxy. it's the orion nebula, horsehead nebula and flame nebula (from right to left)

That isn't truth. It's artistic. I don't know why the guy doesn't admit that.

Sigh. Did I describe this particular photo as a "galaxy photo?" No. Is the point that people are now beginning to be able to take photos of heretofore inaccessible extraplanetary objects, in general? Yes. Do you object to this title? Apparently. Do I care? No. Bored now.

Hi Jess :)

Many red fluorescent proteins are actually orange emitters, but there is no argument that putting their signal into the red channel is OK (heck, I've frequently put RFP into the green channel and GFP into the red channel because the contrast came out better that way, plus there's the fact that I'm putting some 30nm of spectrum into a single channel). Many astrographs do similar things, by shifting radio frequencies into the visible light spectrum because that's the best way to understand the data. Often the particular shift and range compression are chosen for aesthetic purposes, but it's just finding ways of presenting real data. From reading the article, he didn't even use fancy filters (like a hydrogen-alpha or O-III), so there wasn't any arbitrary cutoffs or large wavelength shifts.

Would a 60 minute exposure of an object in a _very_ dim room (the only way to obtain enough signal in this example) be considered manipulation? The human eye would have no chance of seeing anything under those conditions since its integration time 3 orders of magnitude less. Similarly with IR film that just shifts the large input wavelength to a smaller output wavelength. Is this manipulation? And if neither method alone is, would a long exposure of IR film be manipulation?

You ask if this is truth. But in this situation, how are you defining truth? As the human eye actually sees it (which means only 50mm, f/7 and 1/20sec images are allowed)? Or in some other way?

By Hanspeter (not verified) on 08 Oct 2009 #permalink

"You ask if this is truth. But in this situation, how are you defining truth?"

Hanspeter, I think that's a great question. The point is that there are multiple "truths," depending on whether you have the eye of a camera or the eye of a human (or the eye of an owl). Of course, the public is going to make certain assumptions about which truth you are depicting - which is the subject of my next post!

I know I join the discussion a bit late, but for whatever is worth, the only data in that image you may question as not 100% accurate is the color, which in any case, it is still pretty close to the real wavelengths this are of the space emit.

Every star, every piece of gas, nebulosity, it's all there... The way I think about this... Just because we cannot see it doesn't mean it's not real. They say dogs see in black and white, so perhaps for dogs the color green isn't real? We know it is because we can see it, we know it's real, but of course, go tell that to a dog.

A more drastic example: radiologists may process an image to separate tissue from bones. It sure doesn't look like your naked body. Can we say it's not real because we've excluded "very important data" and enhanced just a part of it?

This image of Orion was taken using LRGB filters, so all the light captured is within the visible spectrum. Perhaps what the image shows as pink is actually more red, or what looks purple is blueish, but they are subtle variations because yes, certain areas of astrophotography are a mix of art and science. To say "that isn't the truth" sounds certainly like an opinion someone could have, but it's not... the truth :-)