It can bring tone to one's photography (5)
I believe the answer is:
sepia
'it can' is the definition.
The definition suggests a singular noun which matches the answer.
'tone to one's photography' is the wordplay.
I cannot really see how this works, but
'tone' could be 'e' and 'e' is found within the answer.
'one' could be 'i' (Roman numeral) and 'i' is found within the answer.
The remaining letters 'spa' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'bring' acts as a link.
Can you help me to learn more?
(Other definitions for sepia that I've seen before include "Pigment got from cuttlefish ink" , "Old drawing" , "Colourant" , "Rich reddish-brown colour" , "Brown colour of old photo" .)