I think that term is reserved mostly for actual artwork (renderings, paintings, etc). Some deep-space astronomy pictures are in completely made-up color, often

I think that term is reserved mostly for actual artwork (renderings, paintings, etc). Some deep-space astronomy pictures are in completely made-up color, often because they're taken at wavelengths different than visible light and then color-mapped to look pretty. But the point here is even if you're taking images with a regular camera pointed at the sky, it's pretty much impossible to match "reality".