[mh-]

That depends entirely on what you're doing in that dim lighting. And how much time you spend in it. Spending all of your time in dim lighting is absolutely bad for your vision, or at least that is the contemporary consensus in optometry.

[semiinfinitely]

No it does not depend on what you're doing (eg reading) in the poor lighting- that is precisely the myth.

[HumanOstrich]

[Citation Needed]