6) setting for switching the measuring button, And memory button, P168 – Sekonic Speedmaster L-858D-U Light Meter User Manual
Page 182: P168)

168
6. Functions
6)
Setting for Switching the Measuring Button
6
and Memory
Button
7
To improve the operability, you can interchange the button functions between the incident
light system and reflected light system.
NOTE
●
Standard: Used for measurement in the incident light system.
Memory
Button
Measuring
Button
Measuring Screen
●
Reverse: Used for measurement in the reflected light system.
Measuring
Button
Memory
Button
Measuring Screen
●
Auto: The button arrangement is set to "Standard" when the incident light system is
selected, and to "Reverse" when the reflected light system is selected.
The positions of the Measuring Button and Memory Button are displayed for two seconds
on the Measuring Screen just after Custom Setting has been changed and also just after
the power has been turned on.