11

11.1

© 2002 Lauren Georges

11.2

© 2002 Lauren Georges

11.1

© 2002 Lauren Georges

11.2

© 2002 Lauren Georges

ABOUT THE IMAGE

Great Horned Owl Canon EOS D30 digital camera, 300mm f/2.8 IS, ISO 800, f/3.2 @ 1/125, 16-bit RAW setting, 1440 x 2160 pixels converted to 9.3MB 8-bit .tif, iCorrect and Levels have been applied

When using a film camera, most photographers choose the slowest film speed (ISO speed) that can be used to correctly capture their subjects. The reason for this is that slower speed films result in less grain. This is one of the reasons why so many professional photographers prefer slide films, such as Fuji's Velvia (ISO 50) or Provia (ISO 100), instead of the faster speed films, such as ISO 400 or 800 films. Unfortunately, the electronics in digital cameras also suffer from having the same tradeoff between slow ISO speeds and a low level of grain, or fast ISO speeds and loads of grain, which is usually referred to as digital camera noise.

Furthermore, the process of digitizing analog film by using a scanner also produces digital noise. Therefore, just about any time you edit digital photos, you are likely to have some level of grain or noise. Besides the fact that most photographers usually want to minimize the dreaded grain or noise, as it is not in the original scene, an even more compelling reason to minimize it is most digital photos need some sharpening and digital sharpening, usually makes the grain even more pronounced.

While I'd like to tell you that you are about to learn a technique that will remove all of the noise or grain from any image, I am sad to say that removing those nasty little dots can be somewhat challenging if not outright impossible. The problem comes from trying to digitally soften or smooth out the noise or grain without losing important detail in an image. Images without fine detail make it easy to remove grain, while other images that have grain and important fine detail, such as the feather in the owl in Figure 11.1, make it much more difficult. Some images have few important fine details and so the softening of the grain does not noticeably soften the image.

Many approaches are taken to minimize grain and noise — you notice that I said minimize, because removing it completely is fairly hard. Favorite Photoshop 7 filters for removing grain include blur filters, such as Gaussian Blur, Despeckle, Dust & Scratches, and Median. Some digital photographers who have a severe dislike for grain and noise use two or more of these filters in a specific order, making custom adjustments to each filter's settings as they are applied. Besides using one or more of these filters on the entire image, you can also apply them to one or more of the channels depending upon the characteristics of each channel. Other experts offer valid reasons for changing from RGB to Lab mode to apply filters to remove noise or grain.

Finally, you have actions or plug-ins designed specifically to remove grain and noise from digital photos. Two of the more sophisticated and widely used plug-ins are Grain Surgery (www. vis inf. com) and Quantum Mechanic Pro (www.camerabits. com), both of which I sometimes use when faced with especially difficult noise problems in an image. Fred Miranda (www.fredmiranda.com) has created a set of Photoshop actions for removing grain and banding problems from several specific digital cameras when using specific ISO settings. Noise Reduction Pro is another useful plug-in offered by The Image Factory (www.theimaging fatory.com).

Okay, okay, you are probably saying; get on with removing the grain in the owl image! Before deciding on how to remove the grain, first take a quick look at the image to help determine the best grain minimizing approach to take.

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