lol - sorry, i couldn't resist the little joke. Ok, you enter the material editor - ecosystem. Go to the density tab. There in the middle you see a sphere, should be gray. On the upper left corner of this sphere you click on "variable density". Now you do a right click onto the sphere and tell the system "edit function". There you see to the left 4 groups of icons. You click onto the second of the third group (too much math???) from above. To the lower left corner there now appears a field saying "texture map node". In the right field you have a small little arrow in the lower left corner. There you select the image you want to use! Keep in mind - black is "no material", white is "material" here. But you can invert the image in the upper right corner. Now - listen carefully - here comes the final trick! You exit the function editor. Right beside the sphere with the now mapped image you see a little graph - the filter. You have to edit that too. Or load (for the beginning) a predefinded one. I used from the collection "Saturation" the one "Saturation 50/80%" Gives you an idea how the filter should look like - you of course can create one yourself. Now, don't forget to hit the population button and be happy!

One day your ship comes in - but you're at the airport.