When a spell is cast, can the caster choose to do damage lower than what is rolled? For example if 3d4 is rolled and the result is 8, can the player choose to inflict damage lower than what is rolled?
If yes, does this logic also apply for spell effects that are time based. e.g. the effect lasts 2d6 hours, can the caster choose to have the spell affect last for a shorter period than what is rolled?