Sony HVL-MT24AM Operating Instructions Manual page 31

 With some cameras, the flash will fire automatically in P mode. In this case, the
auto lamp on the macro flash unit comes on and the flash may not fire if the
surrounding conditions are bright.
 The P mode flash program is designed for general subjects, not macro subjects.
When taking macro photos, the depth-of-field may be very shallow. If the
aperture selected by the camera is outside the allowable range, the proper
exposure cannot be obtained (p. 26 - 29).
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