You won't be far (via Docklands Light Railway) from Tower Bridge, Tower of London, St Katherines Dock and the City.
The tube (subway) stations at Tower Gateway/Tower Hill or Canary Wharf will put Central London within easy reach (20-30 minutes).
Docklands itself is very photogenic day and night, but be prepared to be challenged by security types as most of the Docklands area is classed as private property, but I understand you can get a photography permit.
Use this web-site -
http://www.tfl.gov.uk/assets/downloads/standard-tube-map.pdf - to get a tube map, or
http://www.tfl.gov.uk for information generally about public transport in London.