If the photometric area used for HDR is specified, the brightness of images are adjusted based on the brightness in the photometric area.
As the default, the photometric area is set full screen. Usually, it is not necessary to change.
Only when necessary to set the photometric area, click the [Train] button to set a window.
When the photometric area includes an area of which brightness is to be ignored, click the [Mask] button to mask the area to be ignored.