Sony DVS-9000SF User Manual page 209

If you applied the effect dissolve or auto transition temporary attributes in
step 4, the corresponding buttons go off.
When a master snapshot is recalled, the region selection buttons light
according to the saved region information.
To cancel a snapshot recall operation
After saving a snapshot, to cancel the recall, press the [UNDO] button.
Note
It is not possible to cancel recalling a master snapshot.
Creating and saving a master snapshot with the numeric keypad
control block
To create and save a master snapshot with the numeric keypad control block,
refer to the operations in "Creating and Saving a Master Timeline Using the
Buttons in the Numeric Keypad Control Block" (page 191). Note, however,
that in place of the [EFF] button in the numeric keypad control block, the
[SNAPSHOT] button is used.
Snapshot Operations From the Numeric Keypad Control Block
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