In today’s age of digital SLR cameras, the image quality is amazing, but one thing we hear on a regular basis is still the issue of noise or grain in images, especially images shot at low light. One of the greatest issues with photographers is the misunderstanding of noise and how it affects their images, or rather understanding at which point excessive noise becomes detrimental to their images. Many people look for noise in the background of their image, as this is where it is likely to be more prominent, especially if there are darker areas in the background, this is however not as important as checking the detail on the actual subject you are photographing. To a large extent the noise in the background is no issue at all, in reality noise becomes a problem when it starts to affect the detail of the subject you are photographing.
In this tutorial I will go through a quick and fairly simple post processing workflow on how to reduce noise effectively in your images, without affecting the detail of your subject. For this tutorial I am going to use Adobe’s Lightroom 5 and Photoshop CS6. Now there are probably thousands of methods and even third party applications and plugins that also reduce noise, some of which do a fantastic job and some not so much. I simply prefer this method since I find it to be the more effective to suggest as most or at least many photographers out there have access to these two programs or at least versions of them.
So here it goes…
Step 1
Process your image as you normally would in Lightroom, make all the necessary adjustments. When reducing noise, pay close attention to your subject, ignore the noise in the background for now.
Once finished, zoom into your image to see the noise in the background easier.
Step 2
Go back to the grid view (G) in Lightroom and create a virtual copy of the image you have just processed.
Step 3
Open your virtual copy in the develop module and go to the detail tab, all you are going to do here is reset the sharpening amount slider to 0. As soon as that is done go to the Noise Reduction section, increase the Luminance slider until the noise in the background disappears, ignore the plastic look your subject may be developing.
Step 4
Once the noise has been reduced go back to the grid view and open both the processed images, the first one you processed as well as the virtual copy, as layers in Photoshop (as in the image below). Note, be sure to select the virtual copy first, then the originally processed image before opening as layers in Photoshop.
When the images are open in Photoshop you will find the images already layered in the layer panel.
At this point the image with reduced noise should be on top. Check this by zooming in and toggling the layer preview button on and off (as in the image below) in order to see the image with the noise present.
Step 5
In this step we are going to add a layer mask over the top image, if you are unsure how to do this, see the below image for where to click and what the result should be.
Step 6
Once you have added the layer mask, select the brush tool and make sure your foreground and background colours are set to black and white, with black on top, as seen below.
Step 7
Now, as the image on top is the one where the noise has been reduced, we want to brush away the area of the image where we want to reveal the detail, in this case it would be the leopard and part of the branch she’s lying on. As you start to brush press the back slash key (\) and your brush strokes will turn red, I find this easier to see where I’m working. Also, as you brush you will notice that the sharpened image is being revealed from below the noise reduced one. In the following image you will see all the red where the detail will be shown from the image the noise reduced one, which is still on top.
When complete, press the back slash key (\) again to turn off the red and zoom in, you should now see the result quite nicely, a sharp subject with a clean noise free background
If you are satisfied, you can flatten the image if you want to, I prefer to maintain the layers for future use just in case. Then click on save, not save as, and this will save the image back into lightroom.
Here you can do a comparison between the finished image (left) and the original processed image(right) as below.
So as you can see, this process produces great results, I hope it can work for you.
Excellent, thanks for sharing this comprehensive information Brendon.