Photoshop Gaussian Blur often tends to give unnatural Depth Of Field (DOF) effects as the blur is equal all over the image.
By using the Dreamlight Real Lens DOF photo backgrounds, you have the DOF done on location. That means progressive DOF - less blur close to the camera and more of it further away.
On top of this, you get the natural circular lens artifacts, typical of a 300 mm telephoto lens.
Matching DAZ Studio lights included!