Hitachi DK-H200 Operating Instructions Manual page 24

White and black balance adjustment
Black balance adjustment
Black balance requires adjustment in the following situations.
Equipment being used for the first time
Equipment idle for an extended period
Large change of ambient temperature
Gamma setting changed
1. Hold the R button depressed for two second. Black balance is adjusted automatically.
2. The displays the following messages during adjustment.
The lens iris is automatically closed.
ＡＵＴＯ ＢＬＡＣＫ：
Adjustment in progress
3. Adjustment is completed in several seconds and automatically stored in memory.
ＡＵＴＯ ＢＬＡＣＫ：ＯＫ
Adjustment complete
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