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Image Noise

High ISO Noise Suppression

As you increase the ISO (or amplification) of your available light in digital photography it has the effect of introducing noise into your images. While the current range of DSLR's generally produce good results, sometimes the images need a little bit of help.

After testing a number of different products (all the big names that I could find evaluation copies of software for on the net) I have settled on Noiseware Professional.

Overall, with my testing it produced the most effective and natural looking results across a broad range of different subject matter in different lighting conditions.

Pixel Mapping - Olympus

Over time digital camera's can (and do) develop pixels that are either permanently dark (dead pixels) or permanantely bright (stuck). Don't confuse this issue with hot pixels which become apparent on long exposure, low light photography.

Depending on what you intend to do with the photo's and the number of pixels affected it will determine whether this presents a problem or not.

Hot Pixels - Olympus

Image noise may be caused by a number of different reasons, but what I will be discussing here is a specific type of noise commonly known as – "Hot Pixels". Hot pixels are more prevalent in long exposure (more than a couple of seconds) low light photography. The problem worsening as the sensitivity or ISO increases.

Hot pixels exhibit themselves as consistently abnormally illuminated or bright pixels.

Depending on the number and intensity of the affected pixels this may not present too much of a problem. In some cases you won’t even see the effects on the printed image. My suspicions are that you would prefer to eliminate these troublesome pixels. You could use the clone tool on your favorite image editing software to address the problem. This would be alright if you only have a few images to process and they are not too badly affected. But, if you are processing a large number images I doubt that you want to spend all afternoon mastering the clone tool, the novelty will wear off very quickly.