“Every moment of a science fiction story must represent the triumph of writing over worldbuilding.” – M. John Harrison

When writing a fantasy or science fiction novel, authors generally find themselves engaging in quite a lot of world building in an effort to create a world of depth and detail sufficient that the resulting story will appear to readers to have both authenticity and consistency. The general consensus is that having performed that world-building, authors should then leave 95% of it the cutting room floor. (Nobody cares about the complete set of custom rules you developed for how heraldry works in your world. Just describe the design your bad guy has on his shield, and move on.)

Full disclosure: what you’re about to read is the product of my metaphorical cutting room floor, and does not make an appearance in the Sleeping Dragon. But I think it gives an insight into the approach I’ve taken when creating the world of Sleeping Dragon, and I just thought people might find it interesting in itself. I should also say that it also takes a certain liberty in that it describes how the Elven vision of Sleeping Dragon works in the context of our world’s physics, even though Sleeping Dragon’s Manaverse setting runs according to its own form of magic-based physics. But I felt this reasonable in order to avoid the article sinking under multiple layers of recursive meta-references.

Oh, and if you like it, feel free to rip it off for your homebrew D&D campaign!

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A recurring trope in fantasy has been that of Elven senses, and in particular vision, being more highly attuned than the senses possessed by “men” (a.k.a. human beings). Tolkien’s elves, back when this trope was birthed, merely had “keener” vision, but by the time First Edition AD&D rolled along, this ability had been dialled up to a full, Spinal Tap-esque eleven, with Elves that could quite literally see in pitch darkness through “infravision” – an ability that functioned in pretty much the same way as the thermal camera on a police helicopter. (You know, the ones that allow Channel 5 documentaries to show you grainy, black-white-and-alien footage of a scroat-shaped blob abandoning a stolen scooter and sprinting through a housing estate while a bored household name dials in a mock-shocked, censorious narration).

I hated it. (Infravision, not Channel 5 documentaries).

It seemed to me to be crude, unimaginative, unbalanced, and narratively-flawed. Crude, in that it seemed both artificial and shoehorned in, arising not from the setting but from the game-mechanics. Unimaginative, in that instead of thinking of how Elven vision might differ subtly, but significantly from human vision, they’d simply copied our world’s thermal imaging cameras. Unbalanced, in that Elven vision was simply better, with no trade-offs, and life just shouldn’t work that way, even in magical realms. And narratively-flawed, because the ability to see heat is potentially hugely over-powered, giving as it does not only the ability to see in the dark, but to see footprints, to see items that have been touched, sense whether an individual is warm (and thus strong), or hypothermic (and thus week), and even see if machinery has recently been operated.

Essentially, we’d gone from “keen vision” to Star Trek medial/engineering tri-corder.

(Over the years, infravision has dropped out of D&D, replaced with Third Edition’s darkvision, only to then return in Fifth Edition, leading to posts attempting to explain how the hell it all works, and posts that just plain damn (in their own words) rant about how daft it is.

For Sleeping Dragon’s elves, I wanted to take a different tack, one that still respected the trope of broadly superior vision, but was more internally consistent, less ambiguous, more balanced (vision that was better than human in some ways, but worse in others), and most importantly, more interesting from a storytelling point of view.

So here’s where it gets sciency. (Until an actual biologist turns up of course, and points out that I’m talking some degree of bollocks, in which case I’ll immediately point out that when I say sciency, I do of course mean pseudo-science with a shitload of magical frosting).

Sleeping Dragon’s Elves obtain their broadly superior vision from two separate and distinct abilities:

  1. An ability to see in lower light levels.
  2. An abiity to see in the very near infra-red (not to be confused with “thermal” vision).

Low Light Vision

Like canine and felines eyes, Elven eyes incorporate a layer of tissue called a tapetum lucidum, which lies immediately behind the retina and acts as a retroflector, reflecting visible light back through retina. This has the effect of increasing the light available to the photoreceptors at the cost of producing a slightly blurred image.

One side effect of the presence of the tapetum lucidum is that when a bright light is shone into Elven eyes (such as a flashlight), they can glow with an iridescent shade of green.

Essentially, Elves have far superior night vision to human beings at the cost of their ability to resolve detail during the day being slightly reduced. (For reasons that human researchers would love to establish but which the Elves are disinclined to discover, this reduction is believed to be much less than that experienced by cats and dogs, possibly due to the compensatory effect of greater functionality in the “image processing” areas of the brain, or possibly some beneficial side-effect arising from Elves’ supposedly inherently magical nature).

Ability To See In The Very Near Infra-red

In both human beings and Elves, vision is produced by the presence in the eye of photoreceptor cells, of which there are two types, rods and cones. Rods are essentially monochrome but more sensitive, allowing them to function in lower light levels than cones (which is why both humans and Elves see in “black and white” when light levels are low).

Human beings have three types of cones (which is known as Trichromacy), allowing them to see a range of colours across what we term the visual spectrum, with the sensitivity peaks of the three cones being blue, green, and red. (i.e. humans have one type of cone for each of the three primary colours). By contrast, Elves have four types of cones (which is known as Tetrachromacy), with sensitivity peaks for blue, green, red, and the very near infra-red.

A few humans with a rare mutation, various mammals, and birds, also have four types of cones. However, unlike Sleeping Dragon’s Elves, the additional cones don’t cover the very near infra-red. In birds, it extends the visible spectrum into the ultraviolet, while in humans it merely divides the same visible spectrum into four “primary colours” (which means that they see colours in a more nuanced way, but don’t necessarily obtain more visual data).

Now, at this point I need to explain what the very near infra-red is, which means I need to reach back some thirty years to the remote sending module I did as part of my BTEC National Diploma in Cartography and Surveying. (The module was basically about how you can make various kinds of maps using the pictures produced by remote sensing satellites such as Landsat, in case you were wondering).

In my experience, people get very confused when they talk about “infra-red”, and that’s because as a term it covers a huge range of the electromagnetic spectrum. And under that spectrum’s conceptual umbrella are gathered a number of things that we people-in-the-street think of as totally separate, distinct concepts, but which are merely the manifestations of electromagnetic radiation at different frequencies (a.k.a. wavelengths). Going from the shortest frequencies to the longest, we have: gamma rays, X-rays, ultraviolet, visible light, infrared, terahertz waves, microwaves, and finally radio waves.

(I always found it hard to wrap my head around the idea that visible light and radio waves are simply different manifestations of the same core thing at different frequencies, but the good thing is that once you just decide to accept that, the fact that astronomers use radio telescopes to study stars doesn’t seem quite so bizarre).

The key point here is that the very near infra-red is not the thermal of D&D’s infravision that I so hated, but is instead the next colour beyond red. But let’s dig a bit deeper, because there’s more to it.



Both planets and stars emit electromagnetic radiation, and their behaviour in this regard can be modelled according to what physicists call a “black body”, which is a hypothetical body that emits electromagnetic radiation in a “shape” determined by its temperature alone, with its size or structure playing no part. The physics behind this is described by Planck’s Law, which states that as the temperature of a black body decreases, its intensity decreases and the frequency at which it emits electromagnetic radiation moves to longer wavelengths.

In practical terms, this means that:

  1. The Sun emits a lot more electromagnetic radiation in total than the Earth, because it’s a lot hotter.
  2. The frequency at which the Sun emits the most electromagnetic radiation is at a much shorter wavelength than the Earth’s equivalent peak.

The diagram below shows this in graphical form.

Credit: David Babb / Dept of Meteo & Atmos Sci / Penn State University. Used with permission. Thanks David!

The orange line shows the Sun’s output, as dictated by its 6000 degree Kelvin temperature, with the peak wavelength at around 0.5 microns, or as we humans call it, “green”.

Yes, that portion of the electromagnetic spectrum that we humans refer to as light is nothing more than the portion of the electromagnetic spectrum that is the peak output for the star under whose light we evolved.

The bluest colour we can see has a wavelength of about 400 nanometers and the reddest about 700, meaning our visual spectrum is nicely balanced around the Sun’s output. (I think the visual spectrum in the above diagram is for broad effect and not necessarily to scale with the X axis). Had we evolved under a cooler star, with a peak output that lay beyond red in what the above diagram refers to as the “Near IR”, then I suspect that our eyes would have involved to be sensitive to those longer wavelengths.

Meanwhile, the black line shows that the Earth’s peak is at around 10 microns, deep into the infrared, and not surprisingly at the portion of the spectrum sometimes termed “thermal”.

I should point out that the Earth’s line is at a completely different Y scale, being measured against the right rather than left axis. The Sun’s output is so massive that it out-emits the Earth at all potions of the electromagnetic spectrum.

So the very near infrared has nothing whatsoever to do with thermal imaging cameras, or an ability to see in the dark. It’s simply the next colour beyond red, a colour that for various reasons our eyes failed to evolve to see. Whereas “thermal” energy is at the other end of the “infrared” range, where you’ll find the frequencies that newly laid asphalt, people, and hard-revved motor-scooter engines emit as radiated heat energy when hot.

But what would this mean for Sleeping Dragon’s Elves? Well simply that to them, we’re colour-blind. Items that with our three cones might appear to be the same colour might be distinctly different colours to them. For example, to us, trees are green. But in the very near infrared, coniferous and deciduous trees are a totally different shade.

Back in the days where aerial photography used actual film cameras, photographic film was developed that was sensitive to the very near infrared, enabling aerial surveys to map different types of trees, simply by their “colour”. Back in college, when our remote sensing lecturer told us this, it just sounded really, really cool. (It’s what got me thinking about this, way back when).

Now you might be thinking that the fact that an Elf could look at forest from a distance, and know what kind of trees it contains, merely by what colour he or she seems them as, is cute, but no particularly big deal. But consider a human Robin Hood type, who wraps himself in a green cloak, thinking that he’ll be invisible among the green trees? Yeah. That ain’t going to work so well, is it?

You can imagine how human vision would appear to Elves by comparing how dog vision (two cones, one blue, one red-green, which is known as dichromatic vision) appears to humans. (At least to non-colour blind humans. Apologies to the many, many people who are to some degree colour blind, and please be assured that it’s not my intention to imply that you are in some way less than human!)

I once bought my dog a set of balls, one green, one red. Here they are below (for the benefit of those readers who suffer from colour blindness, the red is on the left and the green is on the right):

The first evening, I took the green ball out. Even when it got pretty dark, she was still able to pick the green ball out from the grass upon which it lay. The next lunchtime, in bright sunlight, I took the red ball out.

And she just couldn’t see it when it was lying on the grass. At all.

It was bizarre. She was hunting round for it in circles, repeatedly running past it, while I pointed at it, shouting, “It’s there! There!” After each throw, it would take her twenty to thirty seconds of “quartering the area” to find it. Which was when I figured out that dogs are red-green colour blind, something which a quick Google search on my phone confirmed. (As an aside, this is why dog trainers use blue toys, because that colour’s visible to dogs against everything in nature).

What I think was happening was that to Pebbles, both balls were the same colour, red-green, as was the grass. But the green one was a slightly lighter shade of red-green than the grass, while the red one was the exact same shade of red-green as the grass. If I’d come back later in the year when the grass had faded, we might have found the opposite occurring, with the green ball being the one she couldn’t see.

As an aside to the aside, my wife might point out that if we ignore biological reality, Pebbles is very much her father’s daughter because we (my wife and I) experience many occasions where I desperately quarter an area in search of something that I just can’t see while she screams, “It’s there! There!”, which suggests that were a human woman to find herself married to a male Sleeping Dragon Elf, she’d still find herself having to find things for him, four cones to three be damned!

But to get back to the point, that’s how it would be if a human sharpshooter and his Elven companion found themselves being shot at by our Robin Hood type bandit. You’d have the Elf, to whom the bandit was as visible as he would be to us were he wearing a bright red cloak, pointing, and screaming, “There! There!” while the human desperately scanned across what was to him, a sea of green.

Beyond rendering human camouflage outfits embarrassingly inefficient, the wider visual spectrum of Elven vision and the resulting different, and perhaps richer, way in which they could perceive the world would have psychological and cultural effects. Things which appeared beautiful to humans might appear less so to an Elf, and vice versa. An Elf might rhapsodise about the multi-coloured plumage of a pigeon’s wings, for example, much to the confusion of humans who see only grey feathers. A human would look at a forest and see only green where an Elf would see an array of colours, which might explain why Elves really, really like trees. The Elven equivalent of a Jackson Pollock painting might appear to human eyes to be more akin to the monochromatic paintings of Robert Rauschenberg, while human art might, to elves, appear fundamentally broken.


Imagine a human painter who finds a combination of chemicals that, when mixed, produce a blue colour that matches the blue of the sky. For us, that’s all good. But it’s highly likely that in the frequencies of the very near infra red, this substance will emit a completely different level of energy, with the result that to Elven eyes, the resulting sky in the human artist’s painting would be totally the wrong colour. (Imagine a human artist who’s completely red / green colour blind finding some dirt that to his eyes, is exactly the same shade of red / green as grass, making some paint out of that, and then painting a picture that depicts rolling hills of scarlet grass).

And this is more than merely a difference in art: it feeds both into the belief of Sleeping Dragon’s humans that Elves are essentially alien, and into the specieist belief of Sleeping Dragon’s Elves that humans are cruder, less sophisticated beings. The ability of Sleeping Dragon’s Elves and humans to view the same world in such different ways is yet one more factor keeping their societies apart.

Which ultimately I think’s a lot more interesting than the ability to see glowing blobs in the dark.

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So that’s how Elven vision works in the world of Sleeping Dragon. The Sleeping Dragon will be published on the 24th February 2019. It’s a story set in a realistic fantasy world with a twist, which I’ve described in a series of blog posts of which this is the latest. If you’re a Kindle reader and what I’ve written about my world here interests you, I’d be hugely grateful if you’d consider pre-ordering it at the links below. (If you’re not a Kindle reader, it will be available in paperback at cost of UK £6.99 / US $9.99).

UK Link: https://www.amazon.co.uk/Sleeping-Dragon-Jonny-Nexus-ebook/dp/B07KWFNXVS/

US Link: https://www.amazon.com/Sleeping-Dragon-Jonny-Nexus-ebook/dp/B07KWFNXVS/

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