You would be surprised how much light pollution there is in a big city. If you keep your subjects you are shooting near shop windows, or under street lamps or neon signs, slower lens up to F2.8 can be used with film at 400 speed with acceptable sharpness and tonal range.
Lens shade? My compendium shade always saves the day for me.
Granted, I live in Minneapolis, and not NYC or Chicago.
"Often moments come looking for us". - Robert Frank
"Make good art!" - Neil Gaiman
"...the heart and mind are the true lens of the camera". - Yousuf Karsh