Whilst in Snowdonia, north Wales, I borrowed Adrian Evans’ Lee ‘big-stopper’ neutral density filter. This piece of glass is so black it is impossible to see through it and hence it reduces the exposure by an incredible 10 stops. This has the effect of producing a silk-like appearance of moving water or clouds - and also star trails, since the long shutter speed it allows can pick up the rotation of the earth.
Read my bitesized review of this piece of kit that helped me achieve this shot:
