Tutorial - Sharpening 101

Of all of the Photoshop questions I am asked, questions about SHARPENING top the list. It is one of those things that boggles the mind - how much, when, for what??? I sharpen EVERY photo. I mean EVERY one. Whether it is for correcting some of the sharpness that inevitably gets lost during editing, or for trying to save a slightly out of focus shot - I sharpen.

 I hope this post will clear up a few of those questions. I'm going to be talking exclusively about the Unsharp Mask method of sharpening, what all of those settings MEAN, and when to use them. If you want to play along, open Photoshop or Photoshop Elements, open a photo (any photo) I'll be using a straight out of the camera shot my daughter took at school. Then open your unsharp mask filter. This might be found under Filter>Sharpen Unsharp Mask if you are working in Photoshop CS4, for example. Or you might find it under"Enhance>Unsharp Mask" if you are in Elements 5.0. You may have to search for Unsharp Mask depending on which version of Photoshop you are using.

When your Unsharp Mask dialog box opens you will see 3 settings you can adjust. These are:
1. Amount
2. Radius
3. Threshold

We are going to talk a bit about WHAT each of these settings DOES! That way you can decide what settings you want for each picture. Then I'll run through some basic settings for sharpening in different situations. Good? Good!

1. Amount - This slider determines the AMOUNT of sharpening being applied to the photo overall. Usually you will want to stay within the 50% to 150% range. Going any lower than 50%, you won't see any difference in your photo - and going above 150% is sheer craziness. Craziness I tell ya!!!

2. Radius - This slider determines HOW MANY PIXELS out of the edge the pixels will affect. The lower numbers are best in this case, especially when sharpening things with defined edges, like buildings, architecture, etc. I would advise staying in the .5 to 4 range. 2-4 would be good for portraits or softer subjects. Got it? Good!

3. Threshold - This slider (according to Scott Kelby) determines how different a pixel must be from the surrounding area before it's considered an edge pixel and sharpened by the filter. Wrap your mind around THAT! Sheesh. Basically? The lower the threshold number, the more intense the sharpening will be. Easier? Okay.

Basic, every day, sharpening:

A good, basic sharpening setting for every day photos is:

Amount: 125%
Radius: 1.0
Threshold: 3

You could leave your settings here and use it as an all-around sharpening setting. Easy. You can even apply it twice if you think your photo needs it. This is great for printing photos, whatever. An all-around setting. Okay? Let's move on :)

Sharpening for Portraits:
This is a subtle kind of sharpening for close-up shots of people, things with a softer nature about them (think: puppies, flowers, butterflies, rainbows etc.)

Amount: 130%
Radius: 2
Threshold: 10

 Big-time sharpening:

These settings work for photos that are out of focus and you are trying to save them, OR if it's a photo of something like a piece of architecture which needs some heavy sharpening:

Amount: 70%
Radius: 4 - see? I'm nearing the crazy mark
Threshold: 3

Knock your socks off! You'll notice this a lot on distinct edges etc. Fun.

Web Sharpening:
Okay, this is important. When you are DONE editing and sharpening an image - and now you want to save it for the web, things are going to happen. Remember, when you are printing a photo, it has a resolution of 300 dpi, but when you want to save it for the web, you are changing it to a resolution of 72 dpi. When you do this, the photo often gets a bit blurry and soft - you lose your sharpness. So, you need to compensate by sharpening for the web BEFORE you change the resolution to 72 dpi. Here are the settings you would use:

Amount: 400 (you can always reduce this to 300 or even 200 if it seems too intense)
Radius: 0.8
Threshold: 0 (it will sharpen EVERY edge)

It will look totally over sharp before you resize it to 72 dpi, but it will look much nicer when you post on the web. Does that make sense? You run this sharpening action AFTER you have completely finished your editing AND sharpening for print. Got it?

Without web sharpening:

With web sharpening:

Now that you know what the sliders DO, feel free to play with them a bit. When you really become comfortable and adept at using Unsharp Mask, you'll be able to find the perfect settings that will work with each individual photo to make it look it's best.