Creating Non-destuctive Grain in Photoshop
It’s often desirable to add grain to an image when working in Photoshop. Typically this will be a stylistic choice to achieve a certain look but grain can also be employed during more technical processes.
There are number of ways to add grain effects in Photoshop but, by default, these are all applied destructively since the grain or noise filter needs to be applied to pixel content. Try applying the ‘Noise’ filter to an empty layer and you’ll come up against a dialogue box warning that the ‘selected area is empty’.
The trouble with apply grain or noise directly to our image layer is that it can’t then be undone. Yes, we can use Smart-Objects to keep some control over things but that still doesn’t give us independent control over the grain and the image as the two are now combined.
In the example below I’ve called up the ‘Noise’ filter with my image layer selected. Clicking OK will permanently render the noise on to my image layer. For this particular image, and result I’m trying to achieve, this noise is too fine and too hard so I need to be able to work on the noise as a separate layer.
I’ll look at the other grain filters supplied in Photoshop a little later but, for now, let’s stick with the Noise filter as this has been a part of Photoshop since forever so if you are using an early version you’ll be able to apply this process.
We’ve established that the Noise filter needs pixel content or it can’t function so we need something to act as a carrier layer to hold the grain effect – like most of the good stuff in Photoshop this is where Blend Modes step in!
Create a New Layer, accessing the layer options as the layer is created. If you’ve used the menus to bring up your new layer this will come up by default but if you are used to clicking on the ‘New Layer’ icon you’ll need to hold down Alt/Opt+click to access them.
Set the Blend Mode to Overlay and check the box for “Fill with Overlay-neutral color (50%gray)” at the bottom of the dialogue box.
This function fills the layer with whatever is ‘invisible’ for the blend mode you choose. Since Overlay is one of the Contrast Blend Modes the fill will be 50% Gray. Choosing Multiply would invoke a white fill, whereas Screen would produce a black fill.
You should now have a gray layer ready to take our noise filter but your image will look unchanged as the Blend Mode renders the gray invisible.
Now when we select the ‘Noise’ filter we can see the grain being rendered to our gray layer. I’ve got the settings fairly high here to create a hard grain that I’m going to soften with a little blur.
Still working on our grain layer select Gaussian Blur, we only need enough blur to soften out the grain so will normally be working around 1 Pixel or less – this gives the noise a more photographic look reminiscent of actual film grain.
For this image I wanted to apply grain to mask the effects of some heavy-handed jpeg compression – there also seems to be some soft areas in the skin-tones as a result of cloning. Looking at the side-by-side below we can see the grain helps disguise these image artefacts making the image look more photographic again and less digital. I’ve exaggerated the grain here for the purposes of this demo.
Since the grain exists on a separate layer the effect can be pulled back using the Opacity slider. Changing the layer Blend Mode will also yield different results – Overlay is your default, Softlight will give a more subtle effect, and Linear Light gives a harsher, more dramatic grain.
If you want even further control consider converting your gray layer to a Smart-Object before apply the Noise and Blur filters – you can then adjust these settings at any point later in the editing process.
This same process of using a gray ‘carrier’ layer can be used with any of the grain generating filters in Photoshop.
The ‘Grain’ filter (Filter>Filter Gallery...) allows you to modify Intensity and Contrast and also features several Grain Types. As with the Noise filter this has been part of Photoshop for some time so is a good option if you are working with an earlier version. Personally I prefer the standard Noise filter over this one but they all have their uses.
As of Photoshop CC the Camera Raw functions became accessible as a Filter under the main filter menu. Once inside the Camera Raw filter go to the FX tab. The Grain feature here has sliders for Amount, Size and Roughness which gives great control and yields excellent results.
And finally, bringing us up-to-date, my own personal favourite. As of Photoshop CC 2015 a Noise function was introduced as part of the Blur Gallery. This gives the most comprehensive grain control allowing you to match existing grain patterns in your imagery.
To make sure the grain is applied evenly across the whole layer use ‘Field Blur’. The amount of Blur will not affect our image as we are ‘blurring’ a layer of flat gray but it does have some control over the intensity of the grain – you do need at least 1 px blur or you won’t see any grain. Now select the ‘Noise’ tab to edit the Noise parameters. You can choose between Uniform, Gaussian or Grain with the last giving the most amount of control as all 5 sliders become active.
So there you have it. Complete control over non-destructive grain. Enjoy!!