I... don't think so. It is Ignem as in "heat", not "light". And at any rate Ignem can't change how Intellego sense spells work.
It appears so.
That's an interesting fix.
Roll with what ? With the rule or with the spell description ? I find the rule actually atmospheric and cool. I'm not sure if it's wiser to ignore it or to apply it 
Ehh... Whatever your say ....
אני יכול לכתוב טקסט יותר מסתורי
Bring it on ! It's time those old Berkeley List flamewars get put in the shade.
Well, I think ezzelino is right. It isn't really stated out as such in the rules, but it seems to be how things work. I don't think this makes Intellego useless, only limited. Personally, as an SG I'd prefer it to be more limited, especially in the Mentem department... All it took is a few sentences under the "Limit of the Soul"...
I don't think it works via species. I do think it works just like the relevant species do.
The text says that information is given through the sense "is easily distinguished from mundane information coming through the same sense, but it is subject to the same limitations as the mundane sense". The next sentence gives two examples, one of which is explicitly that "a magical sense that works with vision is no good in the dark", which makes sense when you consider that it is light that allows vision species to be carried away to a great distance.
It isn't clear to me whether this means the information arrives via species, however, or is it just that it is subject to the same "limitations" but species are irrelevant. This is very important to me as the question was raised in the context of a particular tactic - everyone in the party donning a Veil of Invisibility and using Vision of Heat's Light to see each other. Does VoHL "tag" the vision species, as Tugdual suggested above ? Or are the "species" VoHL detects affected by spells that affect visual species ? In this case, this tactic won't work. But if the "limitations" are that light must carry the "Ignem-species", then the spell does work. I don't know. If anyone has any advice, I'd appreciate it.
It all comes down to "What are the 'limitation' of the mundane sense?" Vision doesn't work in the dark, so T:Vision spells don't work in the dark.
Does vision work against people under a veil of invisibility ? Clearly not. So should Vision of Heat's Light fail here too ? Or is the "limitation" only that light needs to carry the species, in which case VoHL will work ? I don't know. It's rather fuzzy.
:shrug: It's an important question for my PCs, that want to use the spell and need to understand whether it will work at night and/or on people under a veil of invisibility.
Well, I was under the impression that you Intellego the earth, seeing the gold/silver/whatever that is within it. So the earth that you're targeting is within vision range, and what you're doing is learning stuff about it. If you can literally see things through walls, this is a problem. Either way, this is a problematic spell, yes.
- scratches head* Because destroying entire armies with a wave of your hand, raising palaces with another, and walking amongst titans and faerie gods is pointless if you can't see things in the dark ?
Magic can allow one to see things in the dark in other ways, e.g. Eyes of the Cat. Hermetic magic has some limitations, like not affecting an unsensed target, that will be meaningless if Intellego isn't restricted, and the game will be harder and less rewarding with more effective Intellego IMHO.
That's a cool idea - but I'm with ezzelino on this. I think you should affect the target with Muto Imaginem (req: Ignem) to make it visible from afar. And everyone could see the heat. Quite a different spell. Or you can just change the way the caster experiences the species, but that's not relevant as then heat won't be carried away far.
+1
Super legacy. Wow.