Today’s Question: Is there any difference in the sharpening that should be applied when you are printing an image compared to sharing digitally? It seems to me that if the sharpening works good for one type of output, it should work well for any type of output. Am I missing something here?
Tim’s Quick Answer: There is indeed a difference. Sharpening should be tailored to the specific output size for the image, and sharpening for print will generally be a bit more aggressive than sharpening for digital display.
More Detail: Sharpening is a process of optimizing the appearance of detail in a photo. In some respects you can think of sharpening as being similar to the notion of getting an image in focus. More specifically, sharpening enables you to compensate for factors that cause a photo to appear less in focus (sharp) than you would like.
When an image is shared digitally, you are essentially sharing the “actual” pixels. In other words, the image should be sized based on the digital display, and the sharpening would be relatively modest. In this scenario, you can apply sharpening based on a preview of the image on your computer’s monitor, and expect that the final result will be comparable.
With printing the process of sharpening is a little more complicated, in large part because it is difficult to evaluate a preview of sharpening when preparing an image to be printed. This is due to the fact that you are previewing the image on a monitor display, while the final image will be printed with ink on paper.
When an image is printed to paper (or similar medium), there is a degree of lost sharpness due to the spreading of ink on paper. This effect is amplified when printing to matte paper as compared to glossy paper. The result is that it is more difficult to preview the final effect when preparing a photo to be printed. Furthermore, it is generally necessary to apply sharpening that appears to be too strong when displayed on your computer monitor, if the intent is to print the image.
In other words, different sharpening needs to be applied when preparing images for digital display as compared to printing. In general, the preview you see on your computer’s monitor can be trusted for most digital displays. When it comes to preparing a photo for printing, you will need to at least slightly over-sharpen in the context of what you see on your monitor, in order to produce a print that looks as sharp as you intend.