Digital GEM: Going Against The Film Grain
Reducing the grain that is found in photographic film has been a problem since the creation of film as we know it.
What is film grain you ask? To be technical, film grain is caused by the silver halide crystals in light-sensitive photographic emulsions. The faster the film, the larger the grain size. The larger the grain size the more evident the film grain becomes. Larger grains, or silver halide crystals, give film a greater sensitivity to light. That is why faster films have more grain.
Digital GEM is a technology that was developed by a company called Applied Science Fiction. The GEM acronym actually stands for Grain Equalization & Management. What DIGITAL GEM does is that it analyzes a film’s grain pattern, extracts all data that is related to image quality, color and sharpness, and removes the grain from the scanned image. This results in dramatically improved images. This is essentially the equivalent of noise reduction in digital images.
So, who should use this technology? It is my opinion that this technology should always be used when any type of film image is to be scanned into a digital format. When applied, this technology can greatly improve the overall quality of an image by reducing or, in some cases, removing the unwanted grain altogether. Using this technology in conjunction with other technologies and photo correction techniques your photographs can have the wow factor that you have always dreamed about.
Even in the world of digital photography these days, most photographers are using some sort of noise reduction technology to clean up there digital images. As part of my regular workflow I use Noise Ninja which is an excellent product that can be used as a Photoshop plugin. It can be run in automatic, which is great for running batch files, or in manual mode.
As part of my regular workflow when scanning in my personal images I always use Digital ICE and Digital GEM with a setting of 3 or 4 out of 5. These settings appear to give the optimum results for reducing film grain on images.
Unlike Digital ICE, Digital GEM appears to work very well on Black and White film as well as Kodachrome films. Digital ICE cannot be used on Black and White film, unless it was developed in color, and has reduced impact on Kodachrome films.
Digital GEM is considered to be part of the Digital ICE4 group of technologies. Also included in this group are Digital ICE, which is used to remove surface defects, Digital ROC, which is used to restore and correct color, and Digital SHO, which is used to optimize exposure and contrast. There are several scanners on the market today that use this technology today. These would include the Nikon Coolscan 5000 and 9000 series film scanners that we use as well as the Epson 4990 flatbed scanner that we use for scanning photographs and large format positives and negatives.