The seascape set is made of the following lee seven5 filters 1x 03 1 stop nd hard grad 09 3 stop nd hard grad and big stopper 10 stop nd filter the big stopper reduces the amount of light reaching the sensor by 10 fstops which allows the use of slower shutter speeds by increasing the length of exposure time you can create a ghostly time passing effect of anything that moves for example the sea clouds waterfalls and people etc neutral density grads are designed to balance light