Astronomers from the Infrared Processing and Analysis Center of Caltech capture images of galaxies and nebulas in grayscale data. Adobe Photoshop accurately translates the representations and remap them into visible colors.
Even the marvels of space need a touch-up every now and then. Although spectators wonder at images sent back to Earth from contraptions like the Curiosity Rover on Mars or the Hubble Space Telescope, there is a lot of work to be done on these imageries before they are circulated.
As this blog from Adobe describes, from time to time it is mostly just a case of sewing images to generate a scenery as with broadcasts from Curiosity, but other times the procedure is more complex.
Photoshop expert and astronomer Robert Hurt who works at Caltech states that when giving out imageries of galaxies and nebulas, his job is to turn information into something perceptible. Hurt mainly takes raw grayscale data from different portions of the continuum and then remaps them into observable shades, typically with green, red, and blue Photoshop layers to generate pictures that are precisely illustrative of the infrared colors that mortal eyes cannot perceive.
The astronomer says that the imageries he helps produce not only have to be visually interesting but also correct to the scientific information. The optics of the camera can generate objects that to a viewer might look like something realistic from the galaxy. These are things NASA want to mop out of the image, because they do not want the public to ponder that there is some creepy planet thing floating out there when there is none.
The end-effect is typically a colossal multi-gigabyte file that comprises layers of data from different telescopes. The overall workflow for this is to primarily take the original observational statistics from the telescope, which is kind of a high-dynamic-range image of the sky. Astronomers will get Hubble's visible light photographs of the same astronomical area and will layer the Spitzer information on top of those to generate imageries, emphasizing the thought-provoking distinctions between the different parts of the spectrum that the citizens can comprehend and appreciate.