I wrote a recent blog entry on simulating digital film grain. This action set builds on that discussion.

http://www.thelightsright.com/CreatingARealisticFilmGrainEffect

There are six actions in the TLR Film Grain Effects action set, organized into two groups: actions intended for RGB color photos and actions intended for Grayscale B&W photos (but which are also compatible with RGB, CMYK, and L*a*b images).

With the actions for RGB images, the intensity of the grain effect varies across the different channels, with the Blue channel receiving the strongest grain effect and the Red channel the least effect. With the Grayscale version, the effect is applied to the composite channel, whether that be Grayscale, RGB, CMYK, or L*a*b.

For B&W conversion of RGB photos, you should select the RGB color actions for a more realistic grain effect. Although, if you want more grain in the Green and Red channels, you might opt for the Grayscale versions. Your choice!

The actions in the TLR B&W Conversion action set are ideal for the color actions. The RGB photo is converted to B&W but it remains in RGB (precisely for additional photographic effects, like the application of a film grain effect). The TLR presets for B&W white conversion with Lightroom 2 and Adobe Camera Raw load into Photoshop as Grayscale mode photographs. They're ready for the grayscale actions.

There are three intensities of film grains to select from: low, medium, and high. The film grain effect is applied as a layer. With Photoshop CS3/CS4, a Smart Filter layer is used. You can adjust any of the settings.

The Technique

The actions perform a number of steps to create a more realistic film grain effect.

The film grain effects start with the basic Add Noise filter. This keeps the action set compatible with older versions of Photoshop. This is applied to a layer with an Overlay blend that's filled with 50% gray. You can intensify the film grain effect by changing the blend to Hard Light or reduce the effect with a Soft Light blend. You can also adjust the layer's opacity.

With an RGB photo, the Add Noise filter is applied separately to the Blue, Green, and Red channels (from bottom to top in the Layers stack). Different settings are used, with the Blue channel receiving the strongest grain effect and the Red channel the lightest. With a Grayscale photo, there is only one channel. The noise in this step has a Gaussian distribution.

The noise is then manipulated to make it clumpier. This is done by applying in turn a Gaussian Blur and the Median filter.

Another pass of Add Noise is applied. This one uses a Uniform distribution for a different pattern. This also helps ensure that there will be noise elements of differing size. This noise is sharpened with USM sharpening instead of being blurred. Sharpening the noise also helps to ensure there is some negative film grain.

The effect of the noise is "rolled off" from the deepest shadows and the brightest highlights. This is done with the layer's Blend If sliders.

Sample Photos

I started with a sample photo from Scotland. As my wife and I were driving between Glasgow, Scotland and Inverness, this genetleman was playing bagpipes along the road at a carpark.

Color film does not have film grain, per se. It uses dye clouds rather than silver halide grains. However, it can have a grainy look. So here is the result of applying the RGB actions, first for low grain and then for medium grain.

These actions were intended primarily for imitiating B&W film effects, so a couple of examples of the actions on B&W photos seems appropriate. The first is a grayscale version before the film effect. The second has medium film grain applied.

The final example used the RGB actions to apply a film grain effect to a photo that was converted to B&W but left in RGB for the film grain effect rather than being converted to Grayscale. If you campare the photos above and below, you will notice that the separate application of film grain to the RGB channels results in less grain effect in the face, hands, and legs. The grass, also.

This is the first version of the TLR Film Grain Effects. Comments about the technique and the results are welcome.

Click here to download the TLR Film Grain Effects action set.

Enjoy!

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