A case of visual aesthetics: Why is the monochrome image superior to the color image?

Last Saturday (July 18, 2026) I posted, Some notes on AI and “fine art” imagery, which included these two images, remarking that the first seemed superior to the second:

But I didn’t ask why it is superior. Now I’m asking: Why?

FWIW, ChatGPT produced the first image based on my prompt. I forget the exact working of the prompt, but it was simple. After uploaded a long document about virtual reading I directed it to create an image for the cover of that document. That color image is what it gave me. I liked the form, but found the color distracting, so I asked it to render the image as a Renaissance engraving, resulting in the first image.

To investigate the question I used Photoshop to alter the color version. For this one I reduced the level of saturation:

Here I rendered the image in monochrome blue:

Finally, monochrome grayscale:

All three strike me as being superior to the original color image. The de-saturated version still has color in it, but the color is not so prominent. The monochrome blue has color information, obviously, but only one hue, so there is no contrast between hues. Finally, the grayscale image has no color information at all. Of the two monochrome images, is one better than the other? At the moment I like the blue better than the grayscale, but I’m not sure it matters much.

But I like the engraving rendition better than either of those. Why? It has a much richer texture. Without bothering to has things out, let’s posit that as part of the reason for the superiority of that version over the original color version.

But that doesn’t explain why the other three are superior to the original. What they have in common is less color information. There’s no color information in the grayscale image and the range of color information in the other two is reduced, drastically so in the blue image.

Why should that matter? Let me speculate. The vision system handles brightness differently than it does hue. Luminance is picked up by so-called rods in the retina while color is picked up by cones. To my eye the color information is just there in the color image. It forms no interesting pattern one its own and it doesn’t seem to be interacting with brightness in any way. It adds nothing but color itself.

Let’s speculate a bit farther. Some years ago Mark Changizi published The Vision Revolution (2009). He argued that the biological purpose of color vision is to allow us to read one another’s emotions more accurately based on gradations in skin color. I find his arguments persuasive. Now, while that may be the primary function of color vision, color vision obviously is not confined to how we see other humans. We use it generally in the world.

Now, let’s look at that image. The only recognizable object in it is that book, and it has very little color in it. The rest of it is just spots, lines and swirls that doesn’t look like anything. But maybe it looks a little like veins beneath the skin, not much, but perhaps enough to “invite” the color system to look for emotional resonance, and fail. It’s that invitation-and-failure that makes the color information, not simply irrelevant, but actively distracting.

Do I believe this? Yes and no. It’s speculation. I just made it up. To move from there to belief I’ve have to come up with a way of actually investigating the question, which is more than I’m in a position to do at the moment.

Mulling. Sometimes monochrome even looks … better in some sense… on human faces. 🤷

— Mark Changizi (@MarkChangizi) July 20, 2026