Jargon central to photography in one way? (5)
I believe the answer is:
argot
'jargon' is the definition.
(argot can mean jargon or slang)
'central to photography in one way?' is the wordplay.
'central to' says the answer is hidden in the clue.
'in one way?' says the letters should be written backwards (the other way round).
'togra' is hidden within 'photography'.
'togra' written backwards gives 'ARGOT'.
(Other definitions for argot that I've seen before include "Groat (anag)" , "Specialised language" , "Cant" , "secret language" , "Patois for groat" .)