Sony HVL-MT24AM Operating Instructions Manual page 46

4
While holding the diffuser by its panel's top tab, press it
against the face of the twin flash unit.
Press the diffuser until it clicks into place.
Notes on using the diffuser
 If the arm is set at the 60° position and used with a wide angle lens, the diffuser
may appear in the image. It is recommended that you always use the diffuser
with the arm set at the 90° position.
 The flash output is reduced when using the diffuser. See page 28 for TTL flash
metering, or page 38 for manual flash metering.

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