Excellent and moody shot, very nice indeed, but I have to agree that the top of the lighthouse is too dark.
I think there is some very clever long exposure feathering and burning going on here and very effective it is too. By very long exposure feathering and burning, I mean temporarily darkening areas of the scene as the scene is being shot. I saw a chap on Smibs TV who did a similar thing in the arctic when shooting the Aurora Borealis using 20 minute exposures, he would hang his sock over certain parts of the lens and move it about and darken parts of the scene - a bit like dodging and burning in the darkroom, except you do it as the scene is being shot.
But of course I maybe wrong and it is an effect achieved on the computer
But still very good and excellent work!
Dave