We went through this river lock on the Douro in Portugal recently. Maximum lift is 35m and I don't think any of my pictures really give much idea of the scale. Mind you it's not easy to photograph, very dark at the bottom and brilliant sunlight on white concrete at the top.
This is a following tour boat
This is our boat at the bottom of the lock (it's 3 decks above waterline so say 8m above water level)
and this is it at the top - the walkway the guy is touching is the same one seen in the second picture.
I'm not asking for critique of these specific snaps but how would you photograph the lock to give a good idea of the astonishing scale. Remember you can't get off to photograph from the structure.