How to Sharpen Photos in Photoshop (Unsharp Mask and High Pass Filter)
Many Photoshop users have had troubles with out-of-focus or slightly soft images and a lot has been written about various sharpening techniques in Photoshop. I’ll try to get two of the more popular techniques a bit closer to the average Photoshop user.
1. Unsharp Mask
This filter works to increase the contrast around the edges of your photo in order to create the impression of increased sharpness. The filter’s dialog box has three sliders that enable you to decide on the amount of sharpness that you want to add to your photo. Since not all the photos that need sharpening will require the same amounts for all the sliders, feel free to experiment with the values. Let’s begin:
The photo that we’ll be using for this tutorial looks pretty nice as it is but it seems that it wouldn’t mind a little extra sharpness.
If you need to color correct the photo (Basic Color Correction in Photoshop) make sure that you do that before the sharpening process. After you’ve done all the color corrections with your photo, open the Unsharp Mask (Filter > Sharpen > Unsharp Mask) filter. You’ll immediately be given the option to set the values for the three sliders that will help you sharpen your photo. The Amount slider gives you the option to set the contrast between pixels and for the best print results set the slider to 100%. The Radius slider determines the number of pixels that are going to be sharpened around the edges. Here, you must be careful not to exaggerate with figures in order not to over-sharpen the photo and make it look grainy and unnatural. Usually, this value is not increased above 3. Finally, the Threshold slider determines the edge pixels – the value of 0 meaning that all the pixels are sharpened, so I usually set this slider somewhere between 2 and 20, depending on the photo. If you want to see what’s happening as you mingle with the sliders, keep the preview box checked.
And the sharpened photo is ready:
2. High Pass Filter
One of the great advantages that this method of sharpening has over the others is that it leaves the non-edge parts of the image untouched. This method helps you avoid all the confusing options and theories that other filters need you to understand.
You simply start by duplicating the background layer (Ctrl+J) and applying the High Pass filter (Filter > Other > High Pass) to the Layer 1. In the dialog box, set the Radius between 1 and 2 pixels. Your image is now completely grey, but when you set the blend mode for the Layer 1 to Overlay, your image will look finely sharpened.
If you want to change the amount of sharpening, you can change the blending mode of Layer 1 from Overlay to Hard Light (to increase the sharpening) or Soft Light (to reduce the sharpening). You can also reduce the amount of sharpening by lowering the layer opacity. These are some pretty simple tips, but I am sure you’ll use them over and over again.
A tutorial by Bonifacio Cruz
