After clicking on the Convert to main node the Choosing Graphical Format window will appear at the right pane of the Batch Converting Dialog.
There is a drop-down list of all available graphical formats. After selecting one of them the child node on the left pane will show current graphical format and it's advanced settings (optional). Only the Icon and Jpeg formats have advanced settings. Icon format has the following options: 16 colors and 256 colors. Jpeg format has options: color depth (8 bits or 24 bits), color type (RGB or Grayscale), Quality (in percentage) and Progressive option. Refer to the Jpeg options topic for more information.
If user converts only one image file with changing it's graphical format, then resulting file extension is automatically changed.