Colour painting to me needs reformation (12)

I believe the answer is:

pigmentation

I'm a little stuck... Click here to teach me more about this clue!

'colour' is the definition.
(I know that pigmentation is a type of coloration)

'painting to me needs reformation' is the wordplay.
'painting to me' anagrams to 'PIGMENTATION'.
However, I am not clear how this is indicated.

Can you help me to learn more?

(Other definitions for pigmentation that I've seen before include "For example, madder" , "Natural colouring" .)

I've seen this clue in The Irish Times.

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