Sharpen Tool
The Sharpen Tool sharpens parts of an image that you paint over. That might sound great, but there are other, better alternatives.
Anyway, below are more details on using this tool.
Sharpen Tool Options
Detailed descriptions of each tool option
Tool Presets
You can create and save a Tool Preset for any tool, which will remember settings that you choose for that tool, so you can quickly and easily select different presets and settings for a particular tool. The degree of usefulness of presets varies, depending on the tool.
You can reset any tool back to its default settings by right clicking on the Tool Presets button and select Reset Tool. Take care not to Reset All Tools, unless that is intended.
Brush Presets
You can change size and hardness and select from a range of brush presets. There are many brushes available and you can also create your own.
Brushes Panel
This panel allows you to customize any brush with a wide range of options and settings, which will change the characteristics of the brush. You can then save these brushes.
Mode
Choose to paint with a range of Blend Modes, for different effects.
Strength
Control the strength, or amount, of sharpening that you do with each brush stroke. I recommend reducing the amount, say to 50%, or lower. It will take slightly longer, but you will have more control.
Be careful, because you can easily go too far with this tool and damage your image.
Brush Angle
If you have a non round brush, you can change the angle of the brush.
It won't make any difference on a round brush.
Sample All Layers
Choose whether to blur just the currently selected layer, or all the layers.
Protect Detail
Choose whether to blur just the currently selected layer, or all the layers.
Pressure Sensitive Size
If you have a pressure sensitive pen and tablet, you can turn on this option, so brush size is controlled by the pen pressure. If this is off, size will be controlled by brush settings.
For non pressure sensitive users, the best way to change brush size is with the square brackets keys [ ].
How to use the Sharpen Tool
The Sharpen Tool is straightforward to use and the steps below describe how to use it. However, in common with a number of Photoshop tools, there are better options for blurring an image, especially if quality is important.
This example follows on from the Blur Tool, which shares the button with the Sharpen tool.
Step 1
Select the Sharpen Tool from the toolbar. Like most tools, it shares the button with other tools and the one that is visible will be the last tool used.
Step 2
Consider what strength you want to work at. I recommend reducing the Strength from the default setting (100), to something like 50 or less. At 100% the image can degrade quickly, so keep a close eye on it. Also, see the next step and work on a separate layer. You can then adjust the opacity of that layer, if you wanted, for a lower amount of blurring.
Step 3
Add a new empty layer and on the Options Bar, select Sample All Layers.
I recommend that you don't sharpen directly onto your image. Working on a new empty layer will enable you to hide the image layer and see exactly where you have sharpened. You will then also be able to delete any part of that layer and try again, if something wasn't perfect.
Step 4
Tick the box to protect detail.
Step 5
Use a larger brush for the general areas, but reduce brush size where more accuracy is required,
Step 6
Use a small brush for more accuracy around things you don't want to sharpen.
Step 7
Here is the sharpened version.
It's that simple. Select the Sharpen Tool and paint with it, though I do recommend doing so on a separate layer, as described in Step 3.
However, there are some issues with this. I have deliberately used the tool at its default Strength setting of 100%. If you use this tool, I recommend using it at a lower strength.
The next Steps illustrate the issues.
Step 8
This is the original, unsharpened version.
See the next step for highlighted problems.
Step 9
When using this tool, especially at 100% Strength, it is so easy to overdo the sharpening.
Compare this screenshot to the previous. As you are working it's very easy to sharpen too much and you have little control, apart from using the tool at a lower Strength.
For a comparison, to get an idea of how bad this is, see the next step, which has been sharpened using the Smart Sharpen Filter.
Step 10
This has been sharpened with the Smart Sharpen Filter at its default settings.
Remove Lens Blur
Amount: 200%
Radius: 1.0
Step 11
This has been sharpened with the Smart Sharpen Filter at stronger settings.
Remove Lens Blur
Amount: 300%
Radius: 2.0
Summary of the Sharpen Tool
The Sharpen Tool is a simple tool. It sharpens the areas that you paint over. If you want to quickly sharpen a small part of the image and quality is not paramount, then it's handy for that. But as with a number of other tools, there are better alternatives which allow you to work more flexibly, non-destructively and with greater control.
If you do use this tool, I recommend you do so on a separate layer.
I recommend using other tools, such as Smart Sharpen or Unsharp Mask. Both are available on the Filters menu and both allow you to use them as a Smart Filter, i.e. on a Smart Object. When working with Smart Filters/Smart Objects, the sharpening is non-destructive and can be edited at any time. They are also better tools for sharpening, as illustrated in the last two steps above.
