Take the mars rovers, for instance. Their color photos are actually ';approximate true color.'; The reason is that there isn't a red filter on the camera equivalent to the red our eyes detect. The color being used for red is 'near infrared' which is more revealing to scientists than true red. (see below)
Most cameras sent into space are monochromatic, with various wavelength filters. Color images are produced by merging three images taken at red, green, and blue wavelengths. If they simply took a color photo, they wouldn't be able to seperate them back into their components with the same amount of detail as an original greyscale of a particular target wavelength.
The various wavelengths are important because scientists are often searching for what the components of things being observed are. They can tell what materials are present in things by colors reflected / absorbed. Since the very expensive craft is not there to sight-see but to do work, its cameras are designed to return the best scientific data, and not the most high-fidelity color.
All said, though, even the eggheads appreciate the beauty of the images themselves, and publish the nice ones in color because they hope the public will enjoy them and be fascinated by them as well, so they work very hard at making their images be as close as possible to what the human eye might see.R photos of objects in space true to what they would appear to the naked eye in terms of color?
Most of the images of colourful nebula and galaxies that we see are taken using several different wavelengths of light and different filters to bring out the colours.
If you were to look through an ordinary telescope most of those objects would look mostly white or grey. The main reason is the human eye can't detect colour when the amount of light is low, so we can't really see the colours.
Images taken with CCD cameras use red, blue, and green filters to bring out the colours.
But the colours aren't artificial - they are really there just not visible to our eyes when the light levels are low.
And things such as infrared or ultraviolet light isn't visible to us at all, so these special instruments are needed to show that type of light.R photos of objects in space true to what they would appear to the naked eye in terms of color?
They can be. Often, though, photos are colored to make them look cooler or let you see frequencies the eye can't normally see.
some are and some are not.it depends on what the astrophotographer wants to do.some of them will use color filter wheels at different exposures (red 15min,blue 10min,green 12min etc...) to try and duplicate the color its supposed to be (according to images previously taking from Hubble,and other telescopes with large apertures that have given the correct color) but some will manipulate the color to enhance the picture to their liking
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