Orford Ness is a fascinating place - well worth buying the guide book for once!
It's NT property and you have to go over and return on their boat so early/late light is probably impossible unless you are working for NT and have special permissions. You also have to stick to the waymarked routes (ground nesting birds and munitions!) and these do not get close to the Pagodas (but do allow you to walk into one of the testing facility/bunker buildings). You can walk right up to the lighthouse though.
It's a vast site and NT are employing a managed decline of the structures - excellent for wildlife but off limits for togs. Wear good walking boots and take a packed lunch.
The best view of the pagodas is from the 'Chinese wall' south of Orford town at dawn...
-------------------- There are two things to aim at in life: first, to get what you want; and after
that, to enjoy it. Only the wisest of mankind achieve the second.
Logan Pearsall Smith (1865-1946)