The red filter, the loss-90 percent, only 200 lumens of red light.

经红色滤光片后，光损失90%，只剩下200流明的红光。

youdao

The red filter, the loss-90 percent, only 200 lumens of red light.

经红色滤光片后，光损失90%，只剩下200流明的红光。

youdao