So the Light spell has a "Target object touched". The weenies I play with decided to cast light on a rope and then claimed that the entire length of the 50' rope was providing light. After all, a rope is an object, they argue.
How hard should I smack them?
Since the sppelldescription says "like a torch", I tend to rule it that way. You don't get more mileage out of this then out of a torch, period. If the cleric wants to make the whole sword of the fighter shine for flavour and coolness, he can do that, but that is about as far as it goes and the light they get in return is equal to a torch. If they want to cast it on 50ft of rope, have them pick a fist sized portion of the rope, preferrably one of the ends.
Anything else would become plain silly. "See this mountain over there? It's one big solid piece of rock. Therefore it is one object, so we can make the whole mountain shine..." And other equally cheesy stuff comes to mind. It's a cantrip, so the light source is already free, has no weight and doesn't use up a hand. I think, asking for more then torch-lighting is a bit too much.
On the other hand, if your players insist on it, there's not much harm in giving them a glowing rope, isn't there? If they want the whole party to shine and twinkle, they can just cast light over and over until every damn piece of equipment is sparkling away. If you want them to stop doing stuff like that, just put them in a situation where they might want to quickly hide the light. Quickly cover the shiny amulet around your neck? Go ahead. Cover 50ft of rope? Not so much...
Edit: Oh, so there's an official errata on this now? Good to know for if I ever start a new campaign with low level chars. Thx Jiggy.
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