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Comment by madradavid | Hacker News Reader

Total noob question here and I apologize in advance. Are these the “actual” pictures or are they “touched up” by an artist ? If they the real pictures then this is truly impressive …

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It's the intensity of infrared(-ish) light hitting multiple sensors with different wavelength filters.

If you were to look at it in person it would be a fairly smooth white patch. The colors are artificially assigned, but not by an artist. You pick a specific color for each wavelength. The Hubble palette is spelled out here: https://www.astronomymark.com/hubble_palette.htm

In case of most space photos, they are not what you would see with your eyes. Usually they capture data differently that how an eye would, and then visualize that. They sometimes strive for getting close to naked-eye perception, but usually it's not a goal.

On this Wiki page you can see multiple such images, and the process described:

https://en.wikipedia.org/wiki/False_color#False_color

They're "touched up" in a scientific way to remove flaws in the telescope (light leaking in from the sides, some distracting aspects of the diffraction patterns that from around stars). The colors come from combining several black-and-white images, taken at different frequencies. You can explore the subjectivity of infrared images by opening them in GIMP and playing with the hue slider.

Well since these images are taken in a different part of the EM spectrum than visible light, the colors are false. But the images aren't touched up in the sense that shapes and sizes are altered.

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