- 1). Choose a high-speed film. Films with an ISO number of 400 or over have visible grain in 8x10 prints. (reference 1) Use a neutral-density filter if your high-speed film is over-exposed at the smallest aperture setting of your lens. Push processing that processes a lower-speed film longer, as if it were a high-speed film, will increase grain in enlarged prints. Filtration during processing and development time can also affect grain for film. Slightly under-exposed film will be grainier than correctly exposed film.
- 2). Use a high ISO setting to increase noise, which is the digital equivalent of grain.
- 3). Enlarge your image to make grain more visible. No matter how low your ISO, whether film or digital, sufficient magnification will always reveal grain or noise structure.
- 4). Use editing software to increase graininess. Most high-end photographic editing programs include options to increase grain.
- 5). Reduce the number of pixels in a digital image using compression algorithms. The smaller the file size a given image is reduced to, the fewer dots per inch, and thus the greater the graininess.
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