- 1). Import the image file into a professional level photo editing program or a free photo editing software programs available online (see Resources section). If you are working with a printed photograph, scan the image into a digital format using a flatbed scanner, or have the image scanned at a professional photo lab.
- 2). Go to the filter or special-effects section of your program and select the sharpening tools with an unsharp mask or sharpen filter.
- 3). Set the sharpen filter settings to the desired amount and press the "Select" or "OK" button. Typical sharpening settings for this type of tool are a "threshold" of 3, a "radius" of 0.5. These settings adjust the pixel edges of the image. These numbers are an excellent starting point for making this adjustment. Changing these numbers might be necessary depending on the degree of sharpness.
- 4). Move the amount setting on the sliding scale based on the sharpening amount, which is usually gauged by percentage points. Be careful not to sharpen too much, or your image will have a strange distorted look. This tool sharpens the actual edges of the pixels, or visual data, in the image.
- 5). Select the preview option from the dialog box and ensure that there is no distortion, and that the image has sharpened or become clearer and crisper.
- 6). Press the OK button or apply button in the dialog box implement the adjustments made to the image.
- 7). Save the image and compare the "before" and "after" images to confirm that your edits helped polish the image in question. If the sharpening tool in your editing program did not work, the image is probably beyond help.
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