I see, thank you for the clarification.
I find these are subjective opinions, which again I guess leads to some confusion. I personally find that at least for myself, I could not look these things up "easily enough", and it took a great many number of hours, spanning a number of days, from a number of different searches, to arrive at the final light-related compilation draft I have, and also accessing not just the internet but also a number of other roleplaying games' light source information statistics to draw conclusions and cross-references. I find nothing about the chart easy or obvious, but I tend to have that problem with a lot of things and I guess that's why I get stuck on doing research on a lot of things, I don't know.
Regarding the lantern, while I appreciate verisimilitude, I suppose I'm of the view that for some things, especially intended to be mysterious, "less is more" - perhaps it's a cop-out, or a cheap literary device, but leaving the ultimate origin of a character or item an unknown, to me, allows it to be an authentic artifact of mystery, not even the true creator, the author, knows how "old" it is or where it came from - it has no particular origin - more than be mysterious for mystery's sake though, this allows a GM to tailor the item to their needs and campaign, however they need, since GM's will do that anyway - to back-write the entire history of the item in a world you don't even know the item is going to exist in, seems questionable, to me, and unnecessary, as far as its purpose, for a tool for a GM to use for NPC or players.