The blur tool is used to soften edges and other areas of high contrast in an image. Some users might use the blur tool to create an out-of-focus effect, while others might use it to deemphasise unwanted harshness or contrast. You can also use the blur tool to soften and blend artefacts left by other image edits, like removing or adding objects or using the stamp tools.

 

To use the blur tool, first select it from the tool box.

 

 

When you select the blur tool, options for controlling it will be presented in the options bar.

 

 

You can click the arrow beside the Brush label to select the hardness and diameter of the brush stroke with slider switches. In the options bar depicted here, the brush diameter is 16 pixels. You can also select a preset brush type from a scroll list if you wish.

 

There is also a drop list labelled Mode in the options bar. From this list you can choose to have the areas you blur darkened or lightened as you make your strokes. You can also choose Normal to proceed without these additional effects.

 

 

The next tool option available in the options bar is the strength slider switch. If you click the arrow next to the strength value box (50% by default), the slider will be displayed. A lower strength setting will make the blur effect more subtle, and you will require more strokes to create a stronger blur. As expected, a higher strength setting results in a fast and obvious blur.

 

Finally, if you place a mark in the Use all Layers checkbox, all of the layers contained in the image will be incorporated in the blur effect. If this box is unchecked, only the active layer will be blurred.

 

Remember, the blur tool effect works best for edges and areas with high contrast. If you use it on an area that is continuous with consistent colour (like empty sky) you will probably notice little difference.

 

To blur part of an image, place your cursor over the area of the image to be blurred and hold your left mouse button down. If you drag your mouse pointer, the blur effect will be applied in a brush stroke corresponding to your mouse movements. If you let your mouse pointer hover, the blur effect will be applied to that one spot as long as you hold the button.

 

 

Here is a subtle example of the blur tool effect. Notice that the shadow of the palm tree on the left has fewer sharp edges and appears to be less focused. This was achieved by painting over the shadow with the blur tool. If you blur part of your image, and choose Edit->Fade Blur Tool before performing any other actions, you can use a slider switch to adjust the opacity of your blur effects. The higher the opacity, the more strongly the blur effect will be seen.