# Can the Ring of X-ray Vision make a dark interior appear lit?

The Ring of X-Ray Vision (Dungeon Master's Guide, pg. 193) says:

While wearing this ring, you can use an action to speak its command word. When you do so, you can see into and through solid matter for 1 minute. This vision has a radius of 30 feet. To you, solid objects within that radius appear transparent and don't prevent light from passing through them. The vision can penetrate 1 foot of stone, 1 inch of common metal, or up to 3 feet of wood or dirt. Thicker substances block the vision, as does a thin sheet of lead.

Suppose I am a pirate. After clearing the top deck of an unfortunate cargo ship, me mateys and I head below deck where the ship's crew have extinguished all of the lanterns to make the interior totally dark. But I have a Ring of X-ray Vision. I speak the command word.

From my perspective, does my X-ray vision cause day light from outside to pass through the upper deck into this lower deck, illuminating the space as if it were day light?

• Fire in the hole! 😮 Is the idea of looking through the main deck to see what's down there first not where you are heading with this? – KorvinStarmast Feb 18 at 15:22
• @KorvinStarmast That is another application, my idea was with illuminating the inside from my perspective while I was down there for the purpose of pillaging and combat, but I think the question is the same for the scenario you describe. – Thomas Markov Feb 18 at 15:23
• I don't have an answer, but I suspect it will boil down to whether "solid objects within that radius" means that the object must reside entirely within the radius. – minnmass Feb 18 at 15:32
• @minnmass That is a possible argument I hadn't even considered. – Thomas Markov Feb 18 at 15:41
• Mmm.. the more I read this description, the more I get confused... If the objects don't prevent light from passing through them, they are not just transparent, they are invisible. Or am I missing something? Maybe we can consider tham as made of glass? – Eddymage Feb 26 at 17:45

As written, yes.

Focusing on this sentence:

To you, solid objects within that radius appear transparent and don't prevent light from passing through them.

If the ceiling (here, the ship's deck) were transparent and didn't prevent light from passing through it, and there were light shining on it from above, the room would be lit. Thus, whatever section of the ceiling is within 30 feet of you should appear, to you, to function as a skylight.

Thematically, this isn't totally unreasonable, because assuming X-ray vision involves being able to see actual X-rays, you're seeing the result of the sun's rays (which, in real life, does in fact emit X-rays—though the rules don't require this) penetrating the deck and illuminating the room for you.

Previously, in 3.5e, X-ray vision resulted in "the viewer seeing as if he were looking at something in normal light even if there is no illumination" for 20 feet. One might speculate that the change in phrasing resulted from a desire to not grant light where there is none (e.g., deep underground), but it's not unreasonable for it to grant access to a light source that is simply blocked by a nearby solid object.

To address a point in another answer that you would not be able to see objects within 30 feet of you: the purpose of the phrase "don't prevent light from passing through them" is to clarify that objects behind them are also illuminated by light passing through the object (it would otherwise require them to be illuminated by a light source that isn't blocked by the object). You should still be able to see them, especially based on the phrasing stating that you can see into objects (it'd be quite annoying if you could only see into an object precisely 30 feet in front of you).

• About addressing my point, that one is based on the "transparent" part not on the light passing through part. (Other than that, nice reference to 3.5e) – findusl Feb 24 at 9:48

does my X-ray vision cause day light from outside to pass through the upper deck into this lower deck

I think this does not make sense. If that was true, the use of the magic object would affect the physical properties of the deck you are looking through but only for your character. If the ring were to allow light from outside to traverse the wooden ship deck then all other characters would also be able to see through.

illuminating the space as if it were day light

Your character would be able to see the lower deck through the wooden wall kind of like in dim light.

It is not an object with a simple "see-through" effect, as it clearly states X-Ray (maybe juste figuratively anyway...), as it would allow you to see what is behind but the wording is sloppy :

To you, solid objects within that radius appear transparent and don't prevent light from passing through them

Objects as we see are so seen because light is received from the object to your eye. The deck floor is in the way, but using the magic ring would allow your character to perceive light from an object to your eye without being blocked (or sense the absorbed ray of light). There is no notion of dim light, because you may not be subject to the sensitivity of your eyes. You perceive therefore you see.

This ring can also be found in Pathfinder in the Ultimate Equipment book and has the following description (emphasis being mine) :

On command, this ring gives its wearer the ability to see into and through solid matter. Vision range is 20 feet, with the viewer seeing as if he were looking at something in normal light even if there is no illumination. X-ray vision can penetrate 1 foot of stone, 1 inch of common metal, or up to 3 feet of wood or dirt. Thicker substances or a thin sheet of lead blocks the vision.

No ambiguity here ! You see through as if you were in day light.

But in conclusion you may have multiple options :

• My earlier interpretation is enough for you :)
• You consider D&D5 description as sloppy and you are free to use one from another system like Pathfinder RPG
• You consider that X-Ray is a radiation that emanates from the character using the ring. That radiation would penetrate through thick objects until that radiation is stopped, and your player would be able to sense the radiation length and get a clear picture as the ability dark vision would work
• None of these options suit you and you are free to clarify the object description in the way that most make sense to you and/or your players !
• The digression about Pathfinder is totally irrelevant in a question about DnD 5e. Downvoted. – nick012000 Feb 27 at 1:23
• @nick012000 Fair enough ! Although as the original material lacked clear definition I took the liberty to quote Pathfinder in order to give another perspective. Moreover it is in fact the exact same definition for the item than in DD3.5 (which sounds less a digression now), but I wanted to quote a book I own and I am familiar with. – Glaerferyn Mar 1 at 10:05

# Let's examine how vision works.

## Light ray vs X rays

Visible light and x-rays are different forms of radiation. X-rays are are just more powerful. Light waves can be stopped by opaque objects, but x-rays are not. X-rays (and light as well) travel at different rates depending on what they are passing through. Denser objects will have a different appearance than fluffier stuff. Medical x-rays capture these different rates on film so dense bone looks different than squishy organs.

These waves, rays, what not, are constantly traveling throughout the world. Just because you cannot see x-rays, does not mean that their radiation isn't out there.

## Eyes are input-only

Light travels in waves from a light source. The light waves are reflected off of surfaces from the outside world which enter the eye, bounce around until they hit photoreceptors, which turns the image into electric impulses, which in turn get interpreted by the brain. So the whole thing starts by waves reflecting off, or passing through, an object.

Eyes are designed to only capture certain wavelengths of light. Some eyes have see farther than others; be it infrared, ultraviolet, or "darkvision". The Ring of X-Ray Vision expands that range so that the wearer can now see the intro that spectrum. It does not change the reality of how light works; only the the eye can now process more types of information.

## "To you, solid objects within that radius appear transparent and don't prevent light from passing through them."

So how does this make sense? Light waves are still light waves and cannot pass through "solid" objects. If it did, then everyone would see it and we already said that this is only a change of input to the wearer.

Also, glass and crystals are transparent or translucent "solids" and light travels through them just fine. So the sentence is being inexact by saying "solid" instead of "opaque".

## Here is how I would explain it...

Consider the simple scenario of looking inside of a wooden chest. To the average character, the wood stops them from seeing inside. But with x-ray vision, they can see through the wood... to a pitch black interior. However, since the spell makes solid objects transparent, from the character's perspective, the wood now acts like glass. This means all the light waves that are hitting the exterior, making the walls a new source of light. From that new source of light, waves travel into the chest illuminating it.

So in the case of your pirate, outside the sun is beating down onthe ship. Light waves hit the hull and the upper deck and reflects off. But for a brief moment, those photons are pressed against the wood. When the pirate uses x-ray vision, the wood is no longer a barrier to the photons on the exterior so it becomes a new light source and illuminates the interior for the pirate's eyes only.

## Almost

You asked, "From my perspective, does my X-ray vision cause day light from outside to pass through the upper deck into this lower deck, illuminating the space as if it were day light?"

A reasonable interpretation is:

From your perspective, your X-ray vision causes light from outside to pass through the upper deck into this lower deck, illuminating the space as if it were light.

See below for the fine points.

## X-Ray is a Metaphor

A reasonable assumption is that "x-ray" is being used as a metaphor, as it is in the real world. In the real world, x-ray vision doesn't mean x-rays in the medical sense, it means being able to see through things, and the exact meaning changes with the narrative. See https://en.wikipedia.org/wiki/X-ray_vision.

## Transparent has a Lot of Meanings

The word transparent means you can see through something. In normal everyday speech, it is used without precision. It's reasonable to say that glass is transparent. Obviously, it isn't perfectly transparent, but it's reasonable to say that glass is transparent, meaning you can still see the glass (usually), but you can also see through the glass.

## What You See

Taking the description as much on face value as possible, a reasonable interpretation is:

Within 30 feet you see everything, except as blocked as described. You see the treasure chest, and the stuff inside. You can look at a book and see all the pages on top of each other. You see the print facing you normally, and you see the print facing away from you reversed. You can look at a companion and see their beating heart, and the blood that beats through it. You just regularly see it all at the same time. In all cases you see in color, and you see the different parts of the object at the same time.

It doesn't make any real-world sense, but hey, magic.

## Light isn't supplied

Inside a pirate ship it would be dark.

Unless there were a light source, and then it wouldn't be dark.

Or unless your 30-foot x-ray sphere intersects with the deck, and it's daytime, in which case to you alone it would appear as if light were passing through the intersection of sphere and deck and lighting up everything in its path. This is the scenario you described, I think.

If you have a trait that lets you see in the dark, such as darkvision, then you can see as described by the feature.

So, if there's light, or if you have the ability to see in the dark, then you can see; otherwise, it's dark.

## Another Thought Experiment

Perhaps another useful thought experiment is to imagine you are standing in a fantasy apartment building assumed to have no stone, metal, or wood such as would block vision as described in the item description, completely un-illuminated, and you are more than 30 feet from any outer surface.

You can't see a thing, it's dark.

You turn on your fantasy flashlight; you can now see out to 30 feet as if the light could penetrate all objects. Where the flashlight is directly shining, you see everything and through everything as if normally illuminated by the flashlight; out of the main beam you see everything and through everything as normally illuminated by a flashlight out of the main beam.

You turn off the light and step to slightly less than 30 feet from an outside wall, such that the 30-foot x-ray sphere and the outside wall intersect in a 6-inch circle; it is daylight outside. You now see within the 30-foot sphere as if there were a 6-inch porthole in the side of the circle.

## Attenuation

An interesting question is, does light appear to attenuate to you? In other words, in the real-world, the light of an object 30 feet away receives less light than a same-sized object 10-feet away from a flashlight, therefore the closer object is more brightly lit. Does the same hold true for you? Again, a lot of room for interpretation, but it is reasonable that where the rules say a torch illuminates to 10 feet, that is not negated by the x-ray vision; but on the other hand, daylight does not come with a radius so that light would illuminate to the other side of the sphere.

## Blocking

Another interesting question is, how does blocking work? In the fantasy apartment building, assume it is built of wood. To my reading, where from your point of view, there is a continuous 3 feet of wood, your vision is blocked there. You can see through a wood wall. Stand on top of the wall such that you are attempting to see through 3 feet of solid wood, it's blocked. Same with stone and metal as described. I don't see it as cumulative. Layers of metal half an inch thick stacked up would not block the vision so long as there was air or non-metal between the layers. How much material between the layers? I don't know, but you might or might not be able to research an answer in your downtime.

## Only Light, and Only You

Perhaps obviously, only you "see the light". It's magic, not physics. No one else sees the light. If daylight shines on the deck, only light comes through. If you're a vampire, you are only affected as if you were standing in light, not daylight.

## What is Reasonable

What is reasonable is subject to interpretation. Many games I have played in write down agreed-upon interpretations as rulings. This might be a good case for such a practice.

# Kind of

You already quoted the relevant parts yourself, the item explicitly says

To you, solid objects within that radius appear transparent and don't prevent light from passing through them.

The statement is clear, to you the deck of the ship does not prevent light from passing through as long as you are within 30 feet of it (assuming it is less than 3 feet of wood and the other limits). And with light passing through to the objects below, they are illuminated.

However there is a catch. If those objects that are now illuminated, are within 30 feet of you, they are, according to the item, transparent to you. So you cannot really see them. RAI, that doesn't make much sense. It would prevent you from seeing things within 30 feet from you, if they are not thick enough to block your x-rays. That is weird. A DM could make them only partially transparent, that it appears like glass or something and it would make sense. (Physics would make these items not illuminated as the light going through them means they don't reflect any light at you. But that is not part of the DnD rules, that is just real world phyisics)

Notably, the statement "don't prevent light from passing through them." doesn't serve any other purpose I can find. The only purpose of the statement is to allow light to illuminate areas for you that usually are not illuminated. If they would just want you to look through the solid objects, transparent would be completely sufficient. This is done for example in the Psionics Third Eye Piercing Sight ability (UA):

Piercing Sight (3 psi; conc., 1 min.). As a bonus action, you gain the ability to see through objects that are up to 1 foot thick within 30 feet of you. This sight lasts until your concentration ends.

A guess as concerning why this is:

If you wish to use your X-Ray vision to look inside a dark room through the wall, you wouldn't see anything. Even with darkvision you would only see colourless and as if in dim light. This part of the Ring of X-Ray Vision allows light to illuminate the room.

• Surely X-ray vision isn't intended to prevent you from seeing anything within 30 feet of you. That would be quite a handicap. – Ryan M Feb 24 at 4:44
• @RyanM I'm just reading RAW, it doesn't always make sense. Don't forget, RAW Archers can shoot further if you cast fog cloud on them. rpg.stackexchange.com/questions/160600/… Also it does not make everything within 30 feet transparent, any material thick enough is visible. – findusl Feb 24 at 9:45