Layer Fusion brings all the power of exposure fusion in a single filter with full control over every aspect of the fusion process.
Layer Fusion is the process of merging 2 layers together by controlling which parts of the top image are added to the bottom. This is exactly the same process of HDR Exposure Fusion but with more direct control of the work flow. So now merging the highlight of one image to the shadows of another has never been easier.
Layer Fusion has 6 different options to select from. Custom Hue, Threshold, Intensity, Highlights, Shadows and Feather.
Custom Hue - Since layer fusion was not only designed for HDR fusion, you can use it mask out areas or color of an image out. To mask out a specific color in an image you simply click anywhere on the screen. Note for this option to have any affect the Threshold value must be greater than 0. The selected color and value are shown to the right.
Threshold - This option determines how close a color can be to the selected Hue before this filter has an affect on it. A value of 0 disabled this part of the filter.
Intensity - This option was added to control rate of transparency applied by the threshold option. So a higher value means pixels become more transparent the close they are to the selected Hue.
Highlight and Shadows - These 2 options allow you to adjust the transparency of each individually rather than by just the Opacity of the entire layer. This option is how Exposure Fusion is achieved. By taking the Highlights of one Exposure and the Shadow of another Exposure you then produce a well exposed single image using 2 differently exposed photos.
Feather - To ensure that the blending process is between the 2 layers is smooth, a feather option was added with a range of 4 - 256 pixels depending on the need. The higher the value the smoother the transition but less highlights and shadows are isolated. The lower the value the sharper the transition between the 2 exposures, this is why the min value is 4 pixels.
Layer Fusion is located under the Layers menu option Layer > Fusion... and is available in 8 and 16bit. For this menu option to be enabled a layer must be added to your photo and then selected as this option only works with layers.