October 15, 2013

"I'm interested in the fakeness of all those colorful photographs of the universe that we've been looking at all these years."

I said, in the course of contemplating what Maureen Dowd said about Robert Redford's hair and after reading that "There are no 'natural color' cameras aboard the Hubble and never have been. The optical cameras on board have all been digital CCD cameras, which take images as grayscale pixels." I also tweaked "the atheist Christopher Hitchens" for "burbling about 'the color and depth and majesty' of the Hubble photographs as he urges us to see the revelations of science as more awe-inspiring than the old stories told by religions." I exclaimed: "But the color is fake! The purveyors of science, like religionists, can scam us too."

Reader Gabriel Hanna emails:
To say that something is a scam [is] to say it is dishonest and done for financial gain.  
Now, technically, I did not say the color in the Hubble photographs is a scam. I said it was fake, and then, in a separate sentence, I stated a generality — "The purveyors of science, like religionists, can scam us too" — which is my standard warning to pay attention and be skeptical.
Astronomers, it is true, are largely taxpayer-supported, they are using the Hubble images to convince people to pay for astronomy. But the other element of a scam is dishonesty, and I do not agree that the Hubble images are dishonest — or if they are, they are no more dishonest than any photography.

Light is inherently greyscale, there is no color in it.  Light has only frequency.  Human eyes are sensitive to three sets of frequencies, and the human brain interprets these as color.  All cameras have to "fake" color in the sense that you accuse Hubble astronomers of faking color, because a machine cannot record a subjective human experience.

Hubble, like any digital camera, records numbers that correspond to frequencies of light.  The colors are put into the images by the algorithm that converts the numbers to an image.  In a film camera the data is collected and stored chemically and the developing process does what software does for digital cameras.

When a photographer adjusts white balance, or shoots in sepia, that is "false color" in the exact sense it is for Hubble images.  We do not call that dishonest in the case of digital photography, and it is not a scam even if the photographer sells the photographs.  Like digital photography, most Hubble images are boring, and for public consumption astronomers select the beautiful ones in the same way that a blogger takes hundreds of shots before she gets one good enough to post. Like digital photography, brightness and white balance of Hubble images might well be adjusted, or colors altered in the same way as shooting in sepia, but if we don't call it a scam in the one case we ought not to call it one in the other.

It is especially unfair in that Hubble extends human capabilities to non-visible wavelengths.  It seems very unfair to say that honesty demands that all radio or x-ray astronomy images be rendered in flat black because humans cannot see those colors, and to do anything else is a "scam."
But I stand by my warning. The scientists do want our money, as Hanna concedes. And people like Hitchens call us to replace religion with science because science is so beautiful. If scientists, seeking dominance, punch up the beauty of their images, we must take that into account as we analyze arguments and implicit pleas for money that are based on the beauty of what they are showing us. The art photographer — processing the camera's digital file — is forthrightly guided by aesthetics. The Hubble images can be presented as artwork manipulated for aesthetic pleasure, but to the extent that they are not — as in Hitchens's argument — it is rational and scientific to catch a whiff of scam.

66 comments:

chuck said...

The colors your eyes see are also fake, set by the response bands of the cones in the retina, but just neural signals, greys if you will, after that. That reality varies person to person and among species.

Ann Althouse said...

@chuck

But the question is what are human beings saying, what arguments they make, what evidence they use, and how we should assess that evidence.

In that regard, I distinguish between the way a photo looks when first downloaded into iPhoto and the way it looks after I use the software tools to make it look the way I want it to look. At that point, it's not the automatic translation of the machine-caught files, it is the product of human intelligence, making it look the way I've chosen to make it look.

If I do that as an artist, you can judge whether you like the way it looks.

If I present the image as science or proof of the "the color and depth and majesty" of the material world, I am making an argument that is less-well supported if the images are tweaked for aesthetic pleasure.

Jim said...

In one sense you are correct, clearly the photographs are, in part, marketing.

Saying that it is a "scam", though, is at least a little ignorant. The cameras capture a much wider frequency range than our eyes can see. They capture the visual range of light, but they also capture much more. So they have two choices, they could make pictures that only use the visual light data which, if I understand you correctly, would be the only "true" pictures. Or they could incorporate all, or at least more, of the information that we have by including the other frequencies. How do you represent those frequencies. Obviously you have to either compress the expanded range down to the visual range, or something similar.

I believe that including as much of the information as possible gives much more of a "true" picture of celestial objects than restricting ourselves to the range that our eyes, for evolutionary reasons, can happen to see.

Having said that, you are correct that they are selective in what information to include and leave out for aesthetic purposes. I would not call this a "scam" though. Both art (e.g. impressionism) and scientific models often try to extract the essential and leave out unimportant details.

PB said...

Sometimes colors are used to illustrate detail or show frequencies that aren't visible to the human eye with some artful selection possible.

HOWEVER, while the Hubble's CCD image sensors are black and white frequency detectors (gray-scale), they do have filters they use so that with successive images using different color/wavelength filters, they can construct a number of color images, including "natural" color or what the human eye would see. So to say that all Hubble images are false color and used to mislead the public is not true and intellectually lacking.

Jim said...

On a somewhat related note, I have said for years that NASA is the best marketer in the world (with the possible exception of DeBeers). I say that as a person with decidedly mixed feelings about NASA.

cubanbob said...

@Ann how are these pictures more fake than the dog pictures you post? Just as you chose which pictures to post NASA chooses the pictures it puts out but in both instances those are reality captured at that point in time as we are able to percive visuall reality.

Fritz said...

One thing my cataract operation taught me is that we all don't see the same color blue. Heck, even my two eyes don't agree.

Bob Ellison said...

I am the only person who actually exists. I behave as though the world that I perceive exists just because that's easy to do, and I get fewer mosquito bites that way.

Hagar said...

How would they show us the sizes, shapes, and variety of those structures if not by the use of colors? It is what our senses can make use of.

PatHMV said...

I don't consider the Hubble images a scam or a fraud, because I have always read the disclaimers. Contrary to suggestions by some commenters, the color is often NOT added to Hubble images the same way that filters are used in a regular digital camera to record different wavelengths.

From the HubbleSite:

The colors in Hubble images, which are assigned for various reasons, aren't always what we'd see if we were able to visit the imaged objects in a spacecraft. We often use color as a tool, whether it is to enhance an object's detail or to visualize what ordinarily could never be seen by the human eye.

Further:

Color in Hubble images is used to highlight interesting features of the celestial object being studied. It is added to the separate black-and-white exposures that are combined to make the final image.
Creating color images out of the original black-and-white exposures is equal parts art and science.
We use color:
• To depict how an object might look to us if our eyes were as powerful as Hubble
• To visualize features of an object that would ordinarily be invisible to the human eye
• To bring out an object's subtle details.


For example, in one well-known photo of the Eagle Nebula:

The final image depicts red light from hydrogen atoms as green, red light from sulfur ions (sulfur atoms with one electron removed) as red, and green light from doubly-ionized oxygen (oxygen atoms with two electrons missing) as blue.
These color reassignments enhance the level of detail visible in the image, because otherwise the red light from hydrogen and that from sulfur would be hard to tell apart.

supermagicman said...

I am an amateur, i.e. backyard, astrophotographer. I capture my photos the same way that Hubble does, with a greyscale ccd camera using different filters to get color images.

From this background I would suggest that you are missing something: the Hubble images, even after much manipulation, still aren't capturing the full beauty of those objects. If you were to view them in person you'd laugh at how poorly the pictures portray their actual magnificence.

Maybe the NASA pictures are scamming us, but if they are it is in the opposite way you think: they're scamming us into believing we are grasping the full beauty of the galaxy.

supermagicman said...

I am an amateur, i.e. backyard, astrophotographer. I capture my photos the same way that Hubble does, with a greyscale ccd camera using different filters to get color images.

From this background I would suggest that you are missing something: the Hubble images, even after much manipulation, still aren't capturing the full beauty of those objects. If you were to view them in person you'd laugh at how poorly the pictures portray their actual magnificence.

Maybe the NASA pictures are scamming us, but if they are it is in the opposite way you think: they're scamming us into believing we are grasping the full beauty of the galaxy.

Illuninati said...

"I also tweaked "the atheist Christopher Hitchens" for "burbling about 'the color and depth and majesty' of the Hubble photographs as he urges us to see the revelations of science as more awe-inspiring than the old stories told by religions."

I agree with Althouse. The scam is not in the colorized photographs themselves but in Hitchens' statement about the colorized photographs which he uses as an example of science vs religion.

Since science does not deal with the human spirit or soul, except for the materialists who deny we even have a spirit, Hitchens is comparing apples to oranges. Beauty is in the eye of the beholder, but if we deny that the beholder exists, then the argument that the material universe is beautiful has no universal verity. That statement does not represent reality beyond that it signifies the momentary arrangement of atoms in Mr. Hitchens brain.

DavidM said...

I never considered this before. Something interesting to consider today while I toil away.....

PB said...

Umm, PatHMV, I don't want to start an argument, and sometimes presenting facts sometimes causes positions to harden, but you might want to go to hubblesite.org and read up about how the Hubble uses filters to create color images.

"Hubble's many filters allow it to record images in a variety of wavelengths of light."

"Many full-color Hubble images are combinations of three separate exposures — one each taken in red, green, and blue light. When mixed together, these three colors of light can simulate almost any color of light that is visible to human eyes. That’s how televisions, computer monitors, and video cameras recreate colors."

In addition to red, green, and blue filters, the Hubble also has multiple infrared and ultraviolet filters to handle some non visible wavelengths.

The arbitrary selection of colors to inform is also discussed.

Anonymous said...

Interesting. The Previous Post's References to Years of Schooling Brought me to Here:

When I think back
On all the crap I learned in high school
It's a wonder
I can think at all
And though my lack of education
Hasn't hurt me none
I can read the writing on the wall

So, of Course: Naked Paul Simon Robot. Already Wore Out the Naked Bob Dylan Robot on the Weekend's Comments.

Was Going to Bring "Kodachrome" around to Gatsby via
Luhrmann's Film's Use of Color to Stimulate the Yearning of Nostalgia:

Kodachrome
You give us those nice bright colors
You give us the greens of summers
Makes you think all the world's a sunny day, oh yeah!

With a Sidestep to:

And everything looks worse in black and white

I selected the Gatsby line "For a while these reveries provided an outlet for his imagination; they were a satisfactory hint of the unreality of reality, a promise that the rock of the world was founded securely on a fairy’s wing" to Contextualize with:

If you took all the girls I knew
When I was single
And brought them all together for one night

Then: Yammer, Yammer, Transit Through Daisy to:

Mama, don't take my Kodachrome
(Leave your boy so far from home)

Which Would - of Course - Synchronize with:

"I see now that this has been a story of the West, after all — Tom and Gatsby, Daisy and Jordan and I, were all Westerners, and perhaps we possessed some deficiency in common which made us subtly unadaptable to Eastern life."

Then:

Realization: Perhaps I Have Already Rode this Horse into the Ground. Sorry, Horse.

I got a Nikon camera
I love to take a photograph

Is Probably All I needed to Say.

Steven said...

Of what are scientists "seeking dominance"? Religion?

Science may be having this effect, but in general scientists are not "seeking" any such thing. The individuals who write books against religion are not representative.

Really, even Hitchens, Dawkins, etc... are not "seeking dominance". By measuring the worth of religion scientifically, they assume dominance. To them, there is nothing to dominate.

Steven said...

Of what are scientists "seeking dominance"? Religion?

Science may be having this effect, but in general scientists are not "seeking" any such thing. The individuals who write books against religion are not representative.

Really, even Hitchens, Dawkins, etc... are not "seeking dominance". By measuring the worth of religion scientifically, they assume dominance. To them, there is nothing to dominate.

Revenant said...

Ann's objection is silly. The Hubble's camera doesn't "see" color, sure, but neither does the human eye.

The brain assembles color information based on monochrome inputs from the three different types of cone cells; the Hubble does much the same thing with its filters.

Scott M said...

If the original images taken by the Hubble are "boring" and they alter those images to get people excited about science, doesn't the phrase, "putting lipstick on a pig" become applicable?

If so, isn't there an inherent dishonesty in putting lipstick on pig? (outside pig make-up contests, that is)

PatHMV said...

PB Reader, I'm not sure what statement of mine you are objecting to or think contradicts the quotes your add. I quoted extensively from the HubbleSite, and linked to it. Sometimes the Hubble colors are more-or-less like normal digital photos, with red, green, and blue filters used. But others, as in the Eagle Nebula example I posted, are entirely "false," in that colors are assigned that in no way represent what the eye would perceive, as when the particular wavelength of red is presented as green in order to help us visualize not what the object looks like to the naked eye, but structures that would otherwise be unperceptible to us.

My comment did not say that it does not use filters, but that it often does not use filters THE SAME WAY as a normal digital camera does. As the Hubblesite notes, it does occasionally make a "true color" image using red, green, and blue filters in a process similar to a normal digital camera, but it also very often does NOT do that, and uses not just filters but computer processing to arbitrarily assign colors that are very different from what would be seen by the naked eye. This is the equivalent to using Photoshop to change a yellow dress to a red dress.

Again, that's not to assert that the Hubble images are "false," because I long ago read the disclaimers about how they are produced, and so understand what I am looking at when they are presented.

Gabriel Hanna said...

Might you be so good as to remove my place of work? Thanks.

chickelit said...

Althouse blogged an example of such color enhancement on the microscopic scale: link

Much of the public regards science as uninteresting and it helps to color their view. But I would reserve the word "scam" for outright fraud in science.

On the other hand, anyone who argues that salesmanship and to some extent showmanship is lacking in science--especially involving public outreach and grantsmanship--is missing the point.

Gabriel Hanna said...

@Ann:In that regard, I distinguish between the way a photo looks when first downloaded into iPhoto and the way it looks after I use the software tools to make it look the way I want it to look. At that point, it's not the automatic translation of the machine-caught files, it is the product of human intelligence, making it look the way I've chosen to make it look.

So was the machine translation. It's made to look the way a stranger thought it should look who didn't know what effect you wanted to achieve.

Cedarford said...

What is real and what is fake? The true enormous electromagnetic spectrum of nature? Seems X-rays and IR are real though we cannot see it, along with magnetism...we have been making pictures for 100s of years..

Or is "reality, not fakery.." just the very limited parts picked up human senses?
Even there, human perception of color just a series of small electric signals our brain interpretes cone response bands, as Chuck said. We could have evolved different and for some reason decided to have cones signals for primary yellow be seen as blue, and the blue we know see be shifted to yellow.

The color perception of other evolved species differs from human animals..No real surprise. Dogs, most livestock aside from poultry, have no sense of any colors along the orange-red band.

Pigeons and honeybees are impressive though - honeybees see colors in the UV band as well, pidgeons have 12 times the cones, see 1 color we don't and have superior ability to discern. Pidgeons also evolved, like many birds, to see magnetism, but those signals form a picture though signals in hearing organs, not eyes.

Gabriel Hanna said...

Furthermore, Ann, your iPhone or digital camera is adjusting white balance every time the light changes, and doing it to make the colors "come out right", according to what the stranger who programmed them thinks they ought to look like. If it's fake for Hubble, it's fake for you, even if you didn't deliberately do the fakery.

Hagar said...

The "scientists" use color designations for their own purposes in studying the subjects of the "photography" (actually that probably should not be in quotes, since it is surely photons that are being recorded, whether within our visible perception or not).
So, they, or "civilian" magazine editors, pick some they consider beautiful to present to the lay public. So, why is that "fakery?"
The pictures are beautiful, some at least, and they do help us see and understand a little of what is out there.

Original Mike said...

"This garden universe vibrates complete
Some, we get a sound so sweet
Vibrations reach on up to become light
And then through gamma, out of sight

Between the eyes and ears there lie
The sounds of colour and the light of a sigh
And to hear the sun, what a thing to believe
But it's all around if we could but perceive

To know ultraviolet, infrared and X-rays
Beauty to find in so many ways
Two notes of the chord, that's our full scope
But to reach the chord is our life's hope
And to name the chord is important to some
So they give it a word, and the word is...

OM
"

Graeme Edge


I'm in the "not fake" camp. You need to expand your mind, Althouse.

OM

CommonHandle said...

That's a narrow interpretation of Hitchens' argument. I don't take it to mean that science "replaces" religion so much as that a sense of the "numinous" can come from something at least as real as a burning bush.

rhhardin said...

Word advice: if you want money, build an observatory, not a detector.

rhhardin said...

If not for cosmology, where would all those skin care products come from.

Original Mike said...

"
OM

The rain is on the roof
Hurry high, butterfly
As clouds roll past my head
I know why the skies all cry

OM
OM
Heaven
OM

The Earth turns slowly round
Far away a distant sound
Is with us everyday
Can you hear, what it say?

OM
OM
Heaven
OM

The rain is on the roof
Hurry high, butterfly
As clouds roll past my head
I know why the skies all cry

OM
OM
Heaven
OM
"

Mike Pinder

Smilin' Jack said...

But the other element of a scam is dishonesty, and I do not agree that the Hubble images are dishonest — or if they are, they are no more dishonest than any photography.

Bullshit. Most photography aims to produce an image of an object that replicates what the eye would see when observing that object directly. Hubble, with rare exceptions, does not do that. What it is doing is worthwhile, but it should have a more prominent disclaimer regarding the colors. As the images are presented now they could certainly be regarded as deceptive.

Original Mike said...

"Most photography aims to produce an image of an object that replicates what the eye would see when observing that object directly."

The human eye can not see objects subtending less than a couple of arc minutes nor dimmer than magnitude 6. It's the whole point of a telescope; to see more than the eye can see.

Original Mike said...

That's not how the Eagle Nebula looks now. It's how the Eagle Nebula looked 7,000 years ago. More fakery?

NotWhoIUsedtoBe said...

I don't like the mysticism of science. Science is observation of the universe. It tells us "what" exists, and sometimes "how" it came to be. It cannot tell us "why." It's a tool of human reason, not reason itself.

If anything, the message of science is our own insignificance. We don't matter beyond the tiny confines of this moss-covered rock hurtling through infinity. No matter what we do here, it has no impact whatsoever on the rest of the universe. Whether we continue to live on Earth or all die tomorrow will not matter to anyone living a few light years away, let alone in the next galaxy.

People who rhapsodize about the beauty of the universe don't get it. The universe isn't beautiful at all. It's a cold place that does everything it can to kill us. Someday it will succeed. It's easy to admire a picture of Mount Everest. It's quite another thing to die there.

Beauty, to me, is survival in a universe almost devoid of life.

n.n said...

Color is a concept which describes a spectrum. The other connotations ascribed to it are a matter of aesthetics.

That said, the material difference between a philosophy of morality (i.e. religion) and a philosophy of materiality (i.e. science) is that the latter is intentionally constrained to observing and interpreting phenomenon within a limited frame of reference due to the requirement that its knowledge be testable and reproducible.

Hitchens is remarking on the subjective appeal and individual perception of aesthetics, which is analogous to the subjective appeal and individual perception of morality.

Sigivald said...

Light is inherently greyscale, there is no color in it. Light has only frequency.

I think there's a hell of a lot less difference than Mr. Hanna does.

There's no difference between "color" and "frequency of light". They're the same thing.

It's ludicrous to claim that the "subjective experience" of color is not "in light", but the equally subjective experience of "greyscale" is, because one is frequency and the other is intensity.

There is no fundamental difference; both are properties of the light itself, and also something we experience.

That we don't all see color identically for biological reasons is true (and equally true of intensity AFAIK, just not as dramatically) - and irrelevant to the "reality" of color vs. intensity.

Lewis Wetzel said...

Revenant wrote:
"The brain assembles color information based on monochrome inputs from the three different types of cone cells; the Hubble does much the same thing with its filters."

The signals that go to the brain from the cones and the rods of the retina are indistinguishable from each other. A 'red' nerve signal doesn't look any different than a 'blue' nerve signal (They are simply electrical potentials). The color and spatial information the nerves convey depends entirely on what they are hooked up to in the brain. Our eyes sense only wavelength information, but our brains create color and space.

Gabriel Hanna said...

@Smilin' Jack:Hubble, with rare exceptions, does not do that.

They are frequently using it for astronomy in non-visible wavelengths--so according to you all those should be printed flat black because humans can't see them--and thus useless--or else they are fake.

chickelit said...

Steven writes...
Of what are scientists "seeking dominance"? Religion? and then expands on it.

Reckoning time for one. Pick up any scientific journal and you'll see "A.D." anno domini and "B.C." replaced with "C.E." and "B.C.E." Are these a better reckoning of time or a move afoot to establish an absolute time scale, for example calling this year 12013?

chickelit said...

@OM: I'm confused by all the "OM"'s in that Pinder verse. Are they Hindu chants or your initials?

Lewis Wetzel said...

Heck, an image is just an interference pattern, and you can't get one of those without an aperture. What does anything 'look like' if their is no eye and mind to create an image from it? It doesn't look like anything.
Most of the things the Hubble looks at are thousands or millions of light years away. You aren't looking at them, you are looking at the light they emitted a long, long time ago.

Bruce Hayden said...

I think that this is pretty silly. Human vision is just way too limited for the colors that we see directly to be all that interesting. Pretty much black and white, maybe merging towards yellow. Not much else. You have stars, and you have space. And pretty much everything else radiates at frequencies outside our human range of vision. So, at a minimum, you pretty much need to compress the frequencies being viewed into the human visual range. But, they do go beyond that, by highlighting some frequency ranges with specific colors, making the photos both more interesting, and more informative.

I am just surprised that anyone ever thought that the photos were real color.

Gabriel Hanna said...

@Sigivald:There's no difference between "color" and "frequency of light". They're the same thing.

No, they are not. They light you perceive as "yellow" could be a combination of red frequencies and green frequencies. Or it could be a frequency between that activities both sets of receptors. Your eyes cannot tell the difference because color and frequency are not the same thing. Color is the human perception of light frequency.

We think of seeing as passive, but it is an active process and large parts of it are only taking place in our brains. You can call color a hallucination if you like--it is in the brain only, it is NOT in the light.

You may think it ludicrous, but it is nonetheless true.

Original Mike said...

" I'm confused by all the "OM"'s in that Pinder verse. Are they Hindu chants or your initials?"

There's a difference?

Roger Sweeny said...

"I am just surprised that anyone ever thought that the photos were real color."

Most people have this strange idea that when the government releases a photo it says is of the Crab Nebula, then the photo shows what the Crab Nebula looks like, color and all. Highly unsophisticated of them but true.

chickelit said...

@Gabriel Hanna: Aren't all the colors we're looking at on our screens made from combinations of just three frequencies: RGB?

Gabriel Hanna said...

@El Pollo Rylan:Aren't all the colors we're looking at on our screens made from combinations of just three frequencies: RGB?

Yes, they are--and some colors cannot be represented that way.

When light comes in that is not R, G, or B wavelengths, then our eyes have to cope as best they can, which sometimes they can't do at all.

Peter said...

The colors are not "fake," they're false.

At least, every time I've looked at these (and similar) astro photos, they've been clearly labelled as "false color."

"Fake" implies that someone's being fooled. No one should be fooled, as they're honestly labelled.

Gabriel Hanna said...

@Roger Sweeney: it says is of the Crab Nebula, then the photo shows what the Crab Nebula looks like, color and all.

Most of the time it does, because you can get a telescope and see it yourself--but an x-ray or radio image won't look like what you see through a telescope because you can't see x-ray or radio.

So, yeah, science is some kind of scam because it's not flat black. Jesus H. Christ.

Gabriel Hanna said...

@Peter: And false color includes every photo taken by a camera that adjusts white balance. It applies to every black-and-white or sepia image.

Fake, I tells ya, it's all fake!

Roger Sweeny said...

Gabriel Hanna and Sigivald,

"Color" and "frequency of light" are identical in one important sense. Take anyone with normal color vision and show them light with a frequency of 730 gigahertz. They will tell you it is blue. Show them light with frequency 550 GHz instead and every one of them will tell you it is yellow.

Color and frequency are not identical because our eyes can be fooled and are all the time. Our eyes have three color detectors that roughly correspond to red, green, and blue. Yellow light will somewhat stimulate the red and green receptors (cones) but not stimulate the blue at all. A television or computer monitor has one red, one green, and one blue phosphor in each pixel. It creates the sensation of yellow by making a red and a green phosphor glow.

You can see this by playing with the colors in Microsoft Publisher or use the sliders to change the R(ed)G(reen)B(lue) in this online color generator. Full red (255), full green (255), and no blue (0) looks like yellow to people's eyes.

https://kuler.adobe.com/create/color-wheel/

chickelit said...

You can see this by playing with the colors in Microsoft Publisher or use the sliders to change the R(ed)G(reen)B(lue) in this online color generator. Full red (255), full green (255), and no blue (0) looks like yellow to people's eyes

A simple Venn diagram also shows this quickly: link

Gabriel Hanna said...

And what I linked to shows a color that cannot be represented by the RGB spectrum of a computer monitor, a very common color used in fog lights and head lights.

The colors you see do not correspond one-to-one with the frequencies of the light you see. Light of different wavelengths can be seen as the same color. Light of the same wavelength can be seen as different colors.

Larry J said...

The portion of the electromagnetic spectrum that's visible to humans is miniscule. I recall an analogy that I heard several months ago. Imagine a number line stretched all the way from Los Angeles to New York as representing the EM spectrum. At one end, you'd start with ULF (ultra low frequency) radio waves (below 3000 Hz) and at the other end of the line would be the highest gamma ray frequencies. One a line of that scale, the portion of that line visible to the human eye would be about the size of a quarter.

As others have pointed out, the imagers on the Hubble detect not only human-visible light but also some of the IR and UV spectrum as well. The Hubble's replacement, the James Webb Space Telescope currently under development (and like almost all NASA programs, years late and grossly over budget) will concentrate on the IR spectrum. Improvements in terrestrial telescope techology make it more cost effective to concentrate on those frequencies that don't penetrate the Earth's atmosphere.

Original Mike said...

@Larry J: The primary reason the James Webb Space Telescope (Is the project still active? There was talk of cancelling it.) is that the key project of the device is the very young universe. Objects of interest are far away, and thus red-shifted into the IR.

Original Mike said...

Of course, all of the Webb images presented to the public will have to be a featureless gray, since we can't see IR light.

Larry J said...

True, Mike. Still, there have been tremendous advances in terrestrial telescope technology that make them very powerful for far less cost than a space telescope. I'm talking about things like laser guide stars, adaptive optics and really huge computer stabilized segmented mirrors.

Back in 1988, I was TDY in Sunnyvale, CA and visited the Lockheed plant where the Hubble was built. I got to see it (through glass) in the green room. It's about the size of a school bus (the big ones, not the short-bus Obama specials). Too bad no one tested the optics before launch back in 1990. As a result of saving millions of dollars doing those tests, we had to spend several hundred million dollars on a repair Shuttle mission.

Original Mike said...

"Too bad no one tested the optics before launch back in 1990."

They did test it. Repeatedly. The real tragedy is that they had two methods for testing. A more laborious ("better") method done infrequently for final testing and a quick and dirty method for routine testing as they were grinding. The two methods were not in agreement regarding the shape of the mirror. Rather than do the responsible thing and reconcile them, the decision was made that the "quick and dirty" method was in error. It turned out, of course, to be giving the right answer. They didn't set the testing jig up correctly when they did the "better" method.

And then to make it all the more tragic, the telescope was in storage for years after the Challenger explosion. All that time they could have pulled it out and determined why they had two different tests giving two different answers.

I cried when the first reports of the misconfigured mirror came out.

Smilin' Jack said...

Original Mike said...
"Most photography aims to produce an image of an object that replicates what the eye would see when observing that object directly."

The human eye can not see objects subtending less than a couple of arc minutes nor dimmer than magnitude 6. It's the whole point of a telescope; to see more than the eye can see.


Sigh...yes, a telescope magnifies size and brightness. I guess you would say that Ann's pictures of dogs are fake because they're not the size of real dogs.

Original Mike said...

"I guess you would say that Ann's pictures of dogs are fake because they're not the size of real dogs."

Huh? I'm not the one crying fraud.

SomeoneHasToSayIt said...
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SomeoneHasToSayIt said...

Just as you would likely instantly note my lack of legal education and understanding were I were to opine on court opinions and reasoning, so too I note your lack of education in matters such as that which bears on this post.

Particularly absent this time is lack of knowledge of Kant/Schopenhauer, who had much to say about the role of the sense receptors versus that 'added' by the brain.

You have a right to your opinion on these matters, of course, but the stubborn sticking to it hints that you may think you already have learned enough in your life and so what is left is mostly just defense. A pity, that.

Ken Mitchell said...

The colors of the Hubble photo aren't any more "fake" than the notes of a song transposed from one key to another.

Our eyes are sensitive to only a fairly narrow band of light, but the universe is lit up on spectra hundreds of octaves above and below our pitiful human eyes. (We see in THIS range because that't the bandwidth that is most transparent in our atmosphere. We evolved HERE - for THIS atmosphere.) The Hubble, and other electronic instruments, can detect electromagnetic radiation over the entire spectrum, and transposing the radiation from ranges where we do not see into light that we can, is no more "fake" than playing a song in the key of G when it was originally written in the key of C.

Roger Sweeny said...

Would it be a fake if someone sold me a photograph that had simply been transposed up an octave? That would put everything into the ultraviolet and I would see nothing but a white piece of paper.