Steven Love

As many of you know digital noise is a very common problem with digital cameras, especially at ISO settings above 200.
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Some of you use programs that are specifically designed to remove noise, such as “Noise Ninja”. But most of you probably use Photoshop, which has a fairly steep learning curve when dealing with noise removal. Just running the image through the general noise reduction filter does not always remove all the noise and sometimes it actually creates other problems.
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Some of the most common problems with the general noise reduction filter is that if it is over used it can create “Banding” and another distortion that looks like jagged blotches where similar colors overlap.
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Through experimentation I have found a way to reduce and in many cases eliminate these distortions using Photoshop.
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First step; change the image mode from 8 bit to 16 bit. I’ve found that the technique seems to be more effective with 16 bit images. If you’re dealing with a JPG image convert it to a TIFF, PSD or PNG and then change the mode to 16 bit.
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Look at the image at 100% on your monitor to gauge the severity of the noise. If the noise is real bad it’ll appear as tiny grains mostly in areas that are not in focus. You also might see multi-colored grains in the shadows of the image.
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While still looking at it at 100% run the image through what is called “Despeckle”. You can find this filter in the same drop down menu that the general noise reduction filter is in. After running the despeckle filter you should see the noise soften a little, but it will still be there.
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Now run the image through the general noise reduction filter with the intensity set to 10 and the Preserve Details set at 100%. The color noise reduction should be set at not more than 25%.
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Again, while looking at the image at 100% size you should see the grains smooth out. If they are not completely gone run the image through the noise reduction again with the same settings except that this time you’ll want to change the color noise reduction to zero. This should remove all of the grains from most images that were taken with an ISO of less than 400.
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After running the noise reduction two or more times you should finally see the noise go away, but this is where Banding and Blotching can occur, especially in areas that are not in focus. The way I removed or at least reduced these distortions was by adding noise.
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I know that this sounds counter-intuitive but it actually works. The key is to add just the right amount of noise. Go to the noise reduction drop down menu and you’ll see at the top of the menu “Add Noise”. When you click on that a window should pop up with a slide bar to set the amount of noise. I’ve found that it is easier to manually type in a setting of 0.5
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You do not want a setting greater than 0.75. That would add too much noise and defeat the purpose of the tool. By setting the “add noise” between 0.5 to 0.75 you will see the banding and blotching suddenly smooth out.
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Only after the noise is removed can you now convert the image back to an 8 bit JPG.
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I’ve found that this technique works with most images. I’ve also noticed that my rate of photo acceptance at the stock sites has risen since I started using this method.
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It is not 100% perfect. Images that were taken with ISOs greater than 400 may not be repairable. But if you only have a moderate amount of noise this should remove most if not all of it.
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And always make sure that you work on a copy of the image, that way if you mess it up you won’t destroy the original photo.
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If any of you have questions or have some additional tips feel free to post them in the comments.
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Thank you.
Steve