4. The Screen Setup of PhotoLine
The Channel List shows all color channels of a document. By using the eyes the visibility of the single channels can be controlled. Alt+click on an eye makes that channel the only visible. The selection defines whether a channel can be edited or not. Channel to Selection copies the active channel to the mask and Channel to Layer creates a new layer based on the active channel. These are only accessible, if there is either only one channel or all channels selected.
If the active layer is an adjustment layer, a special channel will also be listed. This special channel represents the mask of the adjustment layer. If the visibility of the special channel is turned on, it will be drawn the same way as a normal mask (see chapter 4.5.2.5 and chapter 7.10.1.24).
Clicking on the channel thumbnail while holding Ctrl (Window) or Command (macOS), creates a mask based on the channel data. Additionally holding Shift adds the channel to the current mask, Alt subtracts.
Using PhotoLine you usually don‘t need the Channel List, because every appropriate tool and filter has its own channel control.