The DC Metro underground stations have dim lighting. When the Metro was new I went to DC and noticed the subdued lighting. But possibly being younger and the lights and stations newer the lighting was not a hindrance. Now that the underground stations are older and have an accreation of dirt I find that it is intolerably dark. It could be my eyes have aged and I have not eaten many carrots, whatever it is the Metro stations are dark.
Much of the lighting is coming from the ground level pointing up. This would naturally dim over time as dust and dirt tend to fall down on top of ground level lights. Possibly some of the lights have broken or burned out and then have not been replaced. What ever the problem is I found that reading Metro DC station signs was difficult, seeing what was on benches difficult, seeing what material a bench is made out of was difficult and just plain darkness was unfriendly. Tinted windows on the passenger cars did not help with reading unlit station signs from inside the train. The station signs themselves were not contrasted well and seemed small as well as unlit. I found reading a newspaper in the dimly lit stations impossible when waiting for a train.
I do not advocate a blinding brilliance and glaring lights, a subdued lighting effect can be nice but there are several fixes that should be looked at:
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