Illusions, lighting, and reflectance

[generic]

I was mostly referring to copycat effect of light spells (if illusion can create light), invisibility effects (if illusion can remove/bend/reflect light), and darkness shenanigans (if illusion can block/absorb light). I'm not saying you advocated any of those, but that's why I think one should be careful about allowing illusions to create, block or reflect light.

But again, as Ovinomancer said, illusions as described in D&D (and fantasy in general) are irreconcilable with real-world physics. Something's got to give. In the face of this paradox, we've got to accept that illusions won't logically work or be rationally explainable, and go with the same willing suspension of disbelief that we are capable of for many other aspects of the game.

In order to be visible in the real-world, an object as to a) emit in the visible spectrum, or b) reflect the ambient light toward the onlooker (assuming there is ambient light in the first place).

Illusions are magical constructs that can make something visible and look real enough to fool anyone that doesn't physically interact with it, but that doesn't really exist. So far in this tread, it has been theorized that...

- Illusions don't create, absorb or reflect light in any logical ways: it just make the illusory item visible and indiscernible from a real one, because magic.

- Illusions block light and reflect it back to it onlooker (the reason we see them) but don't interact with the physical world in any ways, because magic.

- Illusions don't exist as a phenomenon but as a figment of the imagination of the onlooker. The illusionist therefore doesn't mess with our senses as mush as it messes with our mind. And this figment is the same for everyone, because magic.

Personally, I don't think one explanation is more valid than any other - all require that we ignore the laws of physics as we know them. However, I find that the first one is the simplest to explain and to implement within the RaW parameters of the spell without too much surprises and dubious shenanigans. And yet it remains a very powerful tool in the hand of a clever illusionist.

I know I already posted this, but:

Solution:

Illusions (like thick, coloured smoke), are effectively insubstantial for beings/objects passing through them, and are composed of coloured gases that have been trapped within insubstantial planes of extremely refined (and rather detailed) magical charge. They still block light, and cast shadows, but can't be consider substantial (as they are basically coloured gas and magical fields of directing electric charge.

 

[Ovinomancer]

It seems to me that if changes in environment can reveal an illusion then you can disbelieve an illusion without taking an action and successfully completing an investigation check.

My reasoning is that if something other than an investigation check can reveal an illusion then the spell doesn’t work as written because there is now more than physical interaction and a successful investigation that can cause a character to disbelieve an illusion.

I think every illusion has something about it that can reveal it’s an illusion. I think that something isn’t consistent between illusions and that’s what the investigation check is for.

Why do you think a change in environment dispels the illusion without a check rather than being the reason to check in tge furst place?

Illusory wall without backligting -- nothing to indicate it's an illusion, no reason to investigate.

Illusory wall with odd backlighting -- huh, weird, let's check out that wall .

You're jumping to a strange place and assuming some process not indicated.

 

[Ovinomancer]

I know I already posted this, but:

Solution:

Illusions (like thick, coloured smoke), are effectively insubstantial for beings/objects passing through them, and are composed of coloured gases that have been trapped within insubstantial planes of extremely refined (and rather detailed) magical charge. They still block light, and cast shadows, but can't be consider substantial (as they are basically coloured gas and magical fields of directing electric charge.

Has the problem of not following the spell descriptions. I don't see this as preferable to any other solution, and part of those that color way outside the spell description lines.

Succinctly, it's trying to solve a problem that shouldn't exist.

 

[generic]

Has the problem of not following the spell descriptions. I don't see this as preferable to any other solution, and part of those that color way outside the spell description lines.

Succinctly, it's trying to solve a problem that shouldn't exist.

I guess. It just helps me embrace how illusions could be physically possible without being mental effects.

On the other hand, illusions as mental effects can make sense, as long as their area of effect extends to anyone who can see the illusion.

 

[Laurefindel]

I know I already posted this, but:

Solution:

Illusions (like thick, coloured smoke), are effectively insubstantial for beings/objects passing through them, and are composed of coloured gases that have been trapped within insubstantial planes of extremely refined (and rather detailed) magical charge. They still block light, and cast shadows, but can't be consider substantial (as they are basically coloured gas and magical fields of directing electric charge.

This attempts to explain the “because magic” part but does not really add much to “illusions can block and reflect light” theory.

However, the coloured gases theory doesn’t really explain why suddenly the gases stop being opaque as soon as someone succeed on a INT check or save, but only for that person. Does light partially goes through or not? Is so, why did people ignored this transparency before? If not, why did it become translucent for only a few people? Is there a mental component as well?

In the case where a source of light is blocked to make a room pitch black, does light go through it all this time but people become blind “in their head”? If light never passes through, what happens if one person succeed on the save but not the other? If the illusion becomes translucent, does the source behind now only emit dim light? Is the radius affected?

So the coloured gases solution does not work scientifically either, either because we need to ignore the laws of optics, or because it circumvent them completely by asking the mind to make it real. But I still have issues with illusions making people go blind “in their mind” because it goes well beyond the intended area of effect of the illusion. A minor illusion (making a 5’x5’ AoE) has the potential of affecting a full 40-foot radius.

Illusions are already hard enough to manage. IMO, there is no need to complicate them further.

 

[FrogReaver]

Why do you think a change in environment dispels the illusion without a check rather than being the reason to check in tge furst place?

Illusory wall without backligting -- nothing to indicate it's an illusion, no reason to investigate.

Illusory wall with odd backlighting -- huh, weird, let's check out that wall .

You're jumping to a strange place and assuming some process not indicated.

PC’s aren’t dummies. After they have encountered a few illusions that have the same tell they will devise a method to quickly test for that tell. If they find the tell then they will believe it’s an illusion. No investigation check required.

 

[Ovinomancer]

PC’s aren’t dummies. After they have encountered a few illusions that have the same tell they will devise a method to quickly test for that tell. If they find the tell then they will believe it’s an illusion. No investigation check required.

Okay, then, how does that work? You're proposing it could, but you aren't showing the work. It's the classic 1-2-3 that skips the 2.

1. When there's an illusion,
2. ???
3. Profit!

 

[FrogReaver]

Okay, then, how does that work? You're proposing it could, but you aren't showing the work. It's the classic 1-2-3 that skips the 2.

1. When there's an illusion,
2. ???
3. Profit!

I have no idea what you think is missing.

 

[SkidAce]

Illusory wall discovered by investigation check because wind was blowing through it.

From that point on, the party fighter shoves their spear through/at each wall section they walk by. No investigation check required.

Finds another one 20 feet down hall.

 

[Ovinomancer]

I have no idea what you think is missing.

Me, either. That's the point. You postulated players devoloping some method to detect illusions without checks. I'm looking for what you think that is because it's never happened in my games. I don't think you have anything but a weakly premised, slippery-slope objection. Do you have something more?

- "anticipating another vague response" Spikey