If you want a different angle on street photography in lieu of the usual midtown manhattan location you can try these spots easily accessible by subway:
-Roosevelt Avenue in Queens. Take the 7 train to the last stop (Flushing) or to the Roosevelt Ave/Jackson Heights stop.
-Take the 1 train to 181st and St Nicholas for a busy commercial district in Washington Heights
-Take the B train to Fordham Road in the Bronx for another busy shopping district with lots of foot traffic.
-Take the A,B,C, or D to 125th street in Harlem.
-Take the A,B,C, or D train to 116th street in Harlem.
-Take the L to Bedford to photograph some Hipsters in Williamsburg Brooklyn
-Instead of Coney Island, take the B or Q train to the last stop in Brighton Beach. A heavily russian neighborhood.
For urban landscape-y type stuff, you can try these locatons:
-Take the 7 train to Willets Point, Queens and explore the Iron Triangle - a swath of unpaved roads home to countless autobody shops, chop shops, and junkyard.
-Take the A,B,C or D train to 145th street and explore the historic Sugar Hill and Hamilton Heights section of Harlem.
-Take the A or C train to 190th and visit Fort Tryon Park in Washington Heights. Also home to a medieval French monastery which was taken apart, shipped here, and rebuilt in the park.
-Take the F train to Smith/9th street and walk into Red Hook. The water front Brooklyn neighborhood.
-Take the E train to the first stop in Queens and wander around the Long Island City/Hunters Point/Blissville industrial areas of Queens.
-Take the metro north train to the Botanical Gardens stop in the Bronx and walk into the borough's "Little Italy" neighborhood along Arthur Avenue.
-Visit Propsect Park in Brooklyn.
-Take the 1 train to 125th street and broadway and visit Manhattanville section of Harlem underneath the Riverside Drive viaduct before Columbia University levels the entire neighborhood.
-Take the L train to Graham Street stop and walk through industrial East Williamsburg via Grand Avenue then across the Grand Ave bridge into Maspeth, Queens.
Those are some suggestions for some stuff to do in NYC besides the typical midtown and lower Manhattan tourist attractions.