7. The Menus / 7.6 The Tool Menu

7.6.43 Optimize HDR

HDR images can contain color values smaller than 0% and larger than 100%, but only the range from 0% to 100% is visible.

If you want to modify the visible range of an HDR image, the normal Levels function is not well-suited, because it will show you only the existing values from 0% to 100%, Optimize HDR instead will show you the full spectrum of values, so you can easily define the visible range. Additionally it will show you the minimum and maximum values of the image.

Often in HDR images, the brightness in the dark areas of the image is already correct and should not be changed by increasing the visible range. This is made possible by the Protect Brightness option. If it is activated, the brightness range defined by Range remains unchanged. Of course, the remaining brightnesses must then be compressed so that they still fit into the remaining range.