ABSTRACT
When to sharpen All digital images will require sharpening at one or more stages in the digital capture and image editing process. Even if you use the finest resolution camera and lens, it is inevitable that some image sharpness gets lost along the way from capture through to print. At the capture end, image sharpness can be lost due to the quality of the optics and the image resolving ability of the camera sensor, which in turn can also be affected by the anti-aliasing filter that covers the sensor (and blurs the camera focused image very slightly). With scanned images you have a similar problem: the resolving power of the scanner sensor and the scanner lens optics can lead to scans that are slightly lacking in sharpness. These main factors can all lead to capture images that are less sharp than they should be. When it comes to making a print, this too will result in a loss of sharpness, which is why it is always necessary to add some extra sharpening at the end, just before sending the photograph to the printer. Also, between the capture and print stages you may find that some photographs can do with a little localized sharpening to make certain areas of the picture appear that extra bit sharper. This briefly summarizes what we call a multi-pass sharpening workflow: capture sharpening followed by an optional creative sharpen, followed by a final sharpening for print.
