Thank you lutorm and andrewf for the great replies. lutorm, I appreciate your example of the brightness of galaxies needing to be altered, pretty much just com

Thank you lutorm and andrewf for the great replies. lutorm, I appreciate your example of the brightness of galaxies needing to be altered, pretty much just compressing the dynamic range (borrowed from audio, sorry). I will never picture galaxies in my mind the same way. Thanks to andrewf I got this from the website: The image is a composite of separate exposures made by the WFC3 instrument on the Hubble Space Telescope. Six filters were used to sample narrow wavelength ranges. The color results from assigning different hues (colors) to each monochromatic image. In this case, the assigned colors are: I hope this has some scientific value but I'm suspicious that it has much more of a public relations value. This strikes me as completely dishonest. Pretty up Hubble images so the public will throw as much money as possible at it. Compressing the brightness of objects like galaxies seems reasonable, and I know I've seen accurate images of planets, but combining filtered images, each with a different "pretty" color, is just whoring up deep space.