Heading for photograph not giving the right message (3-5)

I believe the answer is:

off-topic

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'not giving the right message' is the definition.
I can't judge whether this defines the answer.

'heading for photograph' is the wordplay.
'heading for' becomes 'offto' (I've seen this in another clue).
'photograph' becomes 'pic' (short for picture).
'offto'+'pic'='OFF-TOPIC'

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I've seen this clue in The Guardian.

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