Recently I have been working on a new project. This project involves seascapes with extremely long daytime exposures. The images here have been created with the Sigma 24-105 f/4 Art series lens and a both the Canon 1Dx as well as the Sony A7r. The images were created by using a low ISO, High f/stop and then applying the Fotodiox ND1000 10-stop neutral density filter. This filter basically looks black. The way this works is that you prefocus on your subject and then apply the filter. The camera is set to the bulb setting. I use a Phottix Aion Intervalometer (locking digital cable release also) that locks and has a digital timer on it. I know my exposure times through this.