Across:
8 Where one may paint a picture (STUDIO) of where someone is living (STUDIO),
9 Well-built (ATHLETIC) fashion centre (‘fashion’ centre= -H-) for the French (the = -LE-) in lofty structure (attic = AT-TIC) (ATHLETIC),
10 Characters amidst gallant supporters (characters amidst ‘gallant supporters’ = ants = ANTS) from The Hill (ANTS),
11 Its scent is (its scent is = SCIENTISTS) awful (= anagram indicator) to those working in experimental field (SCIENTISTS),
12 Most of (e) the investigation (“case” without “e” = CAS-) on island (-I-) is not (not) restricted (t) (‘not’ without ‘t’ = -NO) (CASINO) to betting establishment (CASINO),
14 Hut (SHE-D) includes parking (-P-) for his companion (‘his’ companion = -HER-) (SHEPHERD), the one associated with crook (hooked staff/crook used by SHEPHERD),
15 To tell you the truth (AS A MATTER OF FACT), the world is not flat, for example (the world is not flat, for example, is AS A MATTER OF FACT)
18 Old (O-) European capital (Riga, capital of Latvia = -RIG-A) overlooking popular (-IN-) lake (-L) (ORIGINAL) that’s untouched (ORIGINAL),
20 Occupied the whole of (FILLED) playing field without paying (‘playing field’ without ‘paying’ = lfield = FILLED),
22 Aidan (AID AN-) Duke (-D) gets Abraham (ABE-) Troy (-T) (AID AND ABET) to support criminal (AID AND ABET),
24 Playing (= anagram indicator) Ludo (ludo = LOUD) is ostentatious, in a manner of speaking (LOUD),
25 Phone message (TEXT-) records (files)? Tip off (f) (‘files’ without ‘f’ = -ILES) (TEXTILES) a number of the Silks! (TEXTILES),
26 Technologically gets rid of alcoholic (‘technologically’ gets rid of ‘alcoholic’ = tengly = GENTLY) gradually (GENTLY).
Down:
1 Curtailed part of (d) the stadium (“stand” without “d” = STAN-) with mid-sized (mid/centre of “sized” = -Z-) area (-A) (STANZA) for the linesman to workout (the linesman/poet / STANZA),
2 No need for dead ends (no ‘need’ for ‘dead ends’ = adds = ADDS) or annexes (ADDS),
3 Youths (youths = BOY S-) opening cans (opening ‘cans’ = -C-) on holiday (-OUT) (BOY SCOUT) prepared to go to the jamboree (BOY SCOUT),
4 Get ready to take flight (TAXI) with what’s bound to concern revenue (TAX-) from island (-I) (TAXI),
5 Charlemagne loses realm (‘Charlemagne’ loses ‘realm’ = chagne = CHANGE) to convert (CHANGE),
6 It’s pretty (DELIGHTFUL) beautiful (DELIGHTFUL),
7 Famous (HISTORIC) wild (= anagram indicator) ostrich (ostrich = HISTOR-C) roaming island (-I-) (HISTORIC),
13 Unfinished (a) museum (Irish Museum of Modern Art = ‘IMMA’ without ‘a’ = IMM-) is the first (-I-) to get donations (-GRANTS) (IMMIGRANTS) from new arrivals (IMMIGRANTS),
14 Time (SPELL) to get all the characters in the right order (get all the characters/letters in the right order = SPELL),
16 A (-A-) writer from foundation (‘writer’ from foundation = -R-) has feast (-DINE-) in ship (S-S) (SARDINES) with swimmers (SARDINES),
17 Behind the scenes (OFF STAGE) it’s not fresh enough (OFF) for Gate’s (gates = STAGE) production (= anagram indicator) (OFF STAGE),
19 Criminal (Don = NOD-) sets up (= reversal indicator) university (University of Limerick = -UL-) college foundation (‘college’ foundation = -E) (NODULE) with small lump (NODULE),
21 Peer’s (peers = EQUALS) question (-Q-) for Unionist leader (‘Unionist’ leader = -U-) in sale (sale = E-ALS) scheme (= anagram indicator) (EQUALS),
23 Foundation (BASE) embraced by suburb as expected (embraced by ‘suburb as expected’ = BASE),
24 Left (L-) for the journalist (-INK) (LINK) to make the connection (LINK).