TrueGrain is a pro-grade tool for accurately recapturing the aesthetics of black and white film with digital photography.
With TrueGrain, you can:
Accurately recapture the aesthetics of particular film stocks-including "lost" films-while retaining an all-digital workflow
Creatively employ credible film aesthetics
Add high resolution film grain information to digital images to elegantly minimize the pixilation effects of upsampling
Match digital imagery to existing film images for restoration and compositing purposes
Achieving the look of film, digitally
Other approaches exist that algorithmically simulate the generic "look" of scanned film by converting to grayscale and adding random noise to resemble film grain. These approaches differ little from what you could readily accomplish by using Photoshop's built-in filters. Moreover, the results are not particularly convincing, because:
real film grain is not random noise
real film grain looks dramatically different across different film stocks
real film grain expresses itself differently based on exposure
TrueGrain's uniqueness lies in its use of empirical data collected, sampled, and profiled under carefully controlled conditions. It draws from a library of historic film stocks, some of which have been out of production for some time, and are not likely coming back.
TrueGrain can actually adapt a digital image to match the measured dynamic range and spectral response of a specific film stock and then correctly incorporate that film's actual film grain into the image, even respecting how that grain expresses itself relative to exposure. The result is an image that is basically indistinguishable from a carefully scanned film frame of the same scene, using the same exposure, stock, and development process.
Hovering your mouse over the 1:1 examples, below, will reveal the underlying digital source image, which is the same in all four cases.
Spectral Response
Black and white film stocks respond differently to different wavelengths of light (colors). In TrueGrain, this particular behavior is expressed during grayscale conversion and is directly related to saturation.
Each film implemented in TrueGrain is carefully profiled for its spectral response (how that particular film responds to different wavelengths of light). At the same time, we typically profile the same film exposed through a variety of color filters. When you select a film, all these profiles are automatically loaded into the Spectral Response tab of the TrueGrain interface where you can select between them.
Grain Scaling & Intensity
Each film implemented in TrueGrain includes laboriously photographed, developed, and scanned samples of genuine film grain from that particular stock. When you select a film, you are selecting the grain that will be applied to your image.
You will see the effect of the spectral response profiles most powerfully in the saturated hues of your images. Below are two contrasting examples of brightly colored peppers. The first shows the normal spectral response for Ilford HP5 Plus, while the second is the same film but through a Wratten 25 Red filter.
The most important controls on the Film Grain tab of the user interface pertain to the scale of that grain. Presets are provided that correspond to the size of the grain exposures that were actually scanned; these vary by film (for example, Kodak TMZ 3200 was only available in 135, while others are available in 120 size). You may also enter in an arbitrary percentage value. The grain size you choose will depend on the dimensions of your source image and the particular results you are seeking.
You also have the option of manually manipulating the control points of the spectral response profile to achieve creative effects that no longer reflect the real-world behavior of the chosen film stock. In the following example, an exaggerated spectral response curve has been arbitrarily drawn for effect.
Dynamic Range
The other side of the coin from spectral response is the overall nonlinear response of a given film stock to brightness. In TrueGrain, this behavior is expressed during grayscale conversion and is inversely related to saturation.
As with spectral response, each film implemented in TrueGrain gets a carefully measured dynamic range profile which is automatically loaded into the Dynamic Range tab of the interface. You will see the effects of the dynamic range profile most powerfully in the neutral tones of your images.
Save and load presets
New in TrueGrain v1.1, you can selectively save and load presets of parameter settings. For example, if you create a custom spectral response curve you really like, you can simply save the Spectral Response settings as a preset and then apply it at any time without disturbing the other settings. Likewise, the new presets feature makes it easier to apply exactly the same custom settings to multiple images. (If you are familiar with the preset system in Lightroom, you should feel right at home with TrueGrain's new preset feature.)

The license of this software is Free Trial Software, the price is $300, you can free download and get a free trial.