Step 4: Prepare the HDR image for output
The generated HDR image looks disappointing... This is because it can't be represented properly on screen without further processing.
An unprocessed HDR image is in a way similar to a film negative or the RAW file of a digital camera. It needs further processing for display or printing. In Photomatix, this processing is called Tone Mapping.
Tone mapping allows you to convert the 32-bit HDR image into a 16-bit or 8-bit image with the entire expanded tonal range of the source HDR image intact.
To open the Tone Mapping window, go to the HDR menu and click on the Tone Mapping menu item.