Saving the rendered image
If a rendered image is displayed, you can save it to a file by clicking on either the save option of the File menu or the equivalent button on the toolbar:
After saving, close the image by clicking on the button with the red bar or press the Esc button or select the Close item on the file menu.
If you want a saved image larger than that visible on the screen, move the slider at the bottom of the display to increase the scale:
After clicking on the Save menu or button, a dialog appears permitting you to select a file type and a file name for saving the data. If the named file image already exists, a thumbnail appears on the right side of the dialog box and you will be asked for permission to overwrite it:
Depending on the output file type chosen, the "Advanced" button may show in the main dialog. Clicking on this pops up a new window with the options available for the type of file chosen, e.g. the quality factor for JPEG formats, or various sub-formats for TIFF.