Actually I have had better luck during the day than at night. Think about it for a minute, if you water is just stained 10' down it's dark as heck in the day time.
However you question about them seeing at night, they can see just fine at night and have caught them on spinner baits at night fishing for bass. I think you just have to let them transition to night and then it's on, but get a light for in the water to draw in bait fish which will draw in crappie.
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