If you have spent any time in a studio shooting people against a white background then you are probably aware that dirty backgrounds are a bane to any photographer. Seamless white backgrounds are a staple in many studios and are perfect for shooting portraits, fashion, pets and many other subjects. But, they get dirty very quickly. So, what is the answer to how you can quickly clean backgrounds in your favorite photographs.
Well, one way is in the studio itself. If you are using vinyl then it can be washed and if you are using a paper background then you can cut off the dirty parts. But these take time, especially if you have limited time with a client or model. Do you really want to spend that time cleaning backgrounds between each set? And constantly ripping off the dirty parts of a paper backdrop gets rather expensive rather quickly.
In my case, I have an infinity cove which is painted. So each time it gets dirty it needs a repaint. This is great if you can do it overnight but, between clients it is impossible as it will not dry. I’m not sure my clients would be happy if they had white paint over them after coming in for a photo shoot.
So we rely on our trusty sidekick to clean backgrounds – Adobe Photoshop.
Using Photoshop to Clean Backgrounds
Now you may have cleaned backgrounds using Photoshop in the past and found that it takes up too much time. After all, if you are editing a batch of 40 or 50 photographs do you really want to spend the majority of your time cleaning a background? I bet the answer is ‘no’. And there are many ways of cleaning a background. You can use the clone stamp tool, healing brush, the dust and scratches filter and even frequency separation. But all of these methods do take time.
The method I have been using for about the last 8 years or so is using the Median filter.
How the median filter works is that it looks at the pixels within a specified radius and it blends the luminance of these pixels. It has been used in the past for reducing noise in parts of the photograph. So if you think of all of your dirt on your background as specks of noise you can see that the median filter should be able to even out the dirt.
Because this blurs the background though it cannot be used on patterned backgrounds or outdoors. It is really only useful for when you are using a plain solid color background – such as white, grey or even black. Usually, a seamless background has no texture so any blurring will not matter.
In the picture above you can see a before and after picture which shows how the dirt has been removed after cleaning the background. And importantly the filter has retained the shadows – as it is averaging out luminance.
Cleaning Backgrounds – The Photoshop Steps.
You can watch our step by step video here, or read on.
- Open your photograph in Photoshop
- Make a copy of the background layer by pressing Ctrl-J (windows) or Cmd-J (Mac). Remember don’t work on your background layer ever.
- Go to Filter, Noise, Median
- Choose a radius for the filter. Usually, this is between about 20-40. You want the dirt to be invisible or blended out in the preview but you need to see definition in the shadows and edges of your subject. Click OK
- The entire picture will now become blurred. So as we only want to blur the parts that are dirty (eg the background) then add a layer mask and press Ctrl-I (windows) or Cmd-I (mac) to invert the mask. You will now just see the original picture.
To reveal the areas affected by the filter you now just need to paint white onto the dirty areas of the background. Doing this will reveal the parts of the layer under the mask.
- Make sure white is your foreground color, choose the brush and set opacity to 100% and flow to 100%. Now paint over the background.
To make the brush smaller or larger then press your square bracket keys ‘[‘ and ‘]’ and if you make a mistake then just paint back over that area with black.
- Create a new blank layer
- Choose a soft brush and set your flow to between 5 and 15%
- Sample color pixels close to the colors you want to even out (use the Alt key and click to sample) and paint over areas to even out the color. Keep sampling and painting as much as you need to.
And that is it.
Cleaning backgrounds in your photographs should only take less than a minute. If there are any parts of the background that are too difficult to remove this way you can now use the healing brush on these left over areas.
I hope this helps you with your photo-editing and if you have found it interesting then please like and share on social media.