Painter gives extremely detailed subject of self-portrait to sovereign (7)
I believe the answer is:
vermeer
'painter' is the definition.
(I've seen this before)
'extremely detailed subject of self-portrait to sovereign' is the wordplay.
'extremely' becomes 'very' (I've seen this before).
'detailed' means to remove the last letter (the word must be end-less or 'de-tailed').
'subject of self-portrait' becomes 'me'.
'to sovereign' becomes 'er' (Abbreviation for Elizabeth Regina).
'very' with its final letter taken off is 'ver'.
'ver'+'me'+'er'='VERMEER'
'gives' acts as a link.
(Other definitions for vermeer that I've seen before include "Jan -, seventeenth-century Dutch painter" , "Dutch painter, 1673-75" , "Painter of 18" , "Jan -, seventeenth century Dutch painter" , "Interior painter" .)