3D - 2

Are most of the cosmic photos we see on tv and text book, artist renderings?

They seem too glamorous to be real

Public Comments

1. Most are coloured or are photographed in a different light spectrum.
2. They seem too glamorous because they are. The colors represent different elements and/or gasses present in the object that is being pictured. The scientists do this so they can identify what makes up the object that they are taking a picture of, so they can better understand it. A person looking at that same object wouldn't see what the picture is showing you. It's not some conspiracy it's just a tool scientist use to understand celestial bodies.
3. Long duration and or "stacked" photos like the link below. Sometimes in black and white and sometimes in color either using a color CCD camera and or using colored filters or specific light wave filters like an H-alpha filters. http://hubblesite.org/ http://www.galaxyphoto.com/
4. They're not artist renderings, but the images are computer manipulated to show the colors. The objects are generally too dim to show color to the human eye even through a telescope. But they do have colors, and these are enhanced by computer in the pictures.
5. Most are genuine photographs. They show lots more detail than we can see because they exposed for long periods of time, picking up faint light our eyes can't see. They may also be representations of other sorts of data, like radio astronomy images. The only ones that are always interpretations are external views of the Milky Way. We can deduce what it looks like from outside, but cannot actually see it from outside. We either draw a picture, or show a picture of a similar galaxy and say "ours looks like this!"
6. It depends on what type of photograph that you are looking at. In cases of scientific study, the photos cannot be altered in anyway, for obvious reasons. In order to be of use scientifically, they must remain in their unaltered state to ensure its information is of value. Most photographs you see have been digitally enhanced to make different elements visible or to reduce the amount of "noise" in a given image. Most noise is created by the heat present from in CCD chips. One could argue that an emission line image of the Orion nebula is not accurate. It would depend totally on the observer. If our eyes were sensitive to hydrogen alpha light, then we would clearly see the red glow of ionizing hydrogen gas. Consider this; is a black and white photo of you not an accurate representation of you? Astronomical images capture what is REALLY there. But because we cannot see it with our eyes, it must be captured with equipment sensitive to that particular wavelength, and subsequently the image must be enhanced to show it in a way that our eyes can perceive it. Two examples from my own imaging experience: 1. This image of the Orion Nebula was taken with an unmodified Canon 300D. It represents the visible light image. http://i32.tinypic.com/dlltvm.jpg 2. This image is the same object, and with the same camera, after it had it's IR Cut filter removed, making it more sensitive to hydrogen alpha light. http://i28.tinypic.com/2lau4jp.jpg
7. If it says it's a photograph, and it's from a reputable source, then it's probably a photograph. Keep in mind that some photographs are not taken in the same frequencies that we see with our eyes, and thus appear in rather bright colors that you would not actually be able to see, even if you had very good eyesight, because they simply aren't there in the visible spectrum. Some photographs are also passed through filters (such as increasing the saturation or contrast) in order to bring out detail, and as such don't look the way they really would.