Rods

Rods are most sensitive to light and dark changes, shape and movement. However, they are not effective at distinguishing colours – in a dim room, we mainly use our rods, but we see practically in monochrome.

Rods are receptor cells are sensitive to light and dark, shape and movement, they deal with most of the image but can not translate colour, at night, rods are only used for night vision

His fishing rods were only used at night.