Across:
   7. Not nice when a planet and sun crash together (10)
   9. Turning heads in high class tavern, inspiring urge (4)
  10. New art, primarily invention over proportion (5)
  11. Class in strange guise... boor! (9)
  12. Dad is sore about minor ways (4 5)
  14. City where most praise being original? (5)
  16. I miss Rome, spin out at non-classical style! (13)
  20. Body right out for pastoral scene (5)
  21. Investigator using force, for first time at fault (9)
  24. Artworks listed together with cryptic clue: a goat (9)
  25. "Georgia" using a Persian lute? This is cheesy! (5)
  26. Lord, look closely! (4)
  27. Naive tenor worked to mental exhaustion (10)
Down:
   1. Dawn of 16 across? Subject of 23 is nurse, oddly (7)
   2. Partial desire (no ire) for Pierre-Auguste, into 16 across? (6)
   3. Stall "loony dregs cried foul" seems oddly popular alternative to Académie show in 1874, featuring 16 across (5 3 7)
   4. Something Turner often rendered? (Maritime, primarily) (5)
   5. Some polite, rational educated folk? (8)
   6. Amazing vim is cat's way of making things happen (8)
   8. Where conference held after war turned crazy toward end (7)
  13. Frank? Yep! Harry? Nope! (4)
  15. Guy from America into 16 across but heterosexual at heart (4)
  16. Cut off from 18, so late developing? (8)
  17. Camille, a father figure of 16 across, or 14's movement	 (8)
  18. These can arouse and I lust... I'm not perfect! (7)
  19. Paul, into 16 across, painting card enthusiasts' zeal and nuances not expected initially (7)
  22. Fancy liquor, one millilitre containing zero grams sodium (6)
  23. Farm, one trusts, protects haystack artist Claude, star of 16 across (5)