Everyone that shoots using a paper white seamless background will recognise the problems cleaning up spots and stains on the paper while retouching. Especially the floor will become dirty very quickly. Changing the paper very often is a way to avoid the stains and spots but can become an expensive task.
Take a look at a shot I made during a recent shoot. I cropped the image to only show the floor of the seamless background.
Seamless background dirty floorThis can take a long while to clean up by hand using the healing brush or clone stamp tool. I know I have been doing that for hours and hours in the past. Not a great way to fill up your day.

Another option to make life easier is to blow out the white background so the spots and stains won’t be as visible. But blowing out the background also means changing the image. Maybe you don’t want a blown out background, maybe you want the shadows to be visible. A seamless background that is completely blown out on the floor doesn’t really look good because your subject/model will seam to be floating in mid air.

My solution is very simple and super fast!
First of all I made a copy of the layer and in the filters menu I selected blur/surface blur.
surface blurPlay around with the radius and threshold until you can’t see the spots and stains in the preview. I used a radius of 20 and a threshold of 25 for this image.
Rendering the surface blur might take a couple of minutes depending on the performance of your computer.
Now all the spots and stains are gone, but so is all the detail. Time to add a layer mask and fill the mask with black to hide the effect. This way all the detail is visible again.
Now with a soft white brush with opacity set to around 60% paint (on the mask) on the floor. Don’t worry too much if you hit the shoes for a small bit because you won’t notice it when you go over the edges a small bit. Paint the harder spots and stains for a second time to make sure you can’t see them anymore.
maskAnd there you go. All the spots and stains are gone but shadows and detail in the shoes and pants is still there.
tut_seamless_postHope this trick will save you some time editing the seamless white backgrounds so you can spent your time on being creative.