Operating the preview windows
Preview windows display the zoomed-out preview of the file.
Preview windows for the left-hand and the right-hand sides are synchronised.
This means that scrolling or zooming in one of the panes is reflected in the second pane.
The bar between the preview windows (see image below) contains a number of operations that you can perform.
The operations are:
Drag
Select this tool and drag the image.
Zoom area
Pick this tool, then select an area you want to zoom in.
Zoom In
Pick this tool and zoom in the images one step a time
Zoom Out
Pick this tool and zoom out the images one step a time
Zoom to fit
Press this button to zoom the image to fit into the preview window.