Dorian FitzGerald paints dizzyingly intricate portraits of unsettling opulence and his commitment — in time, in precision, in physical pain — matches his subjects nicely, if only in its embodiment of an extreme. More accurately, perhaps, they serve as foils: FitzGerald’s deep, near-obsessive care versus the absurdly casual excess of the super rich. At Clint Roenisch Gallery, he may set new records for over-the-topness: a massive work depicting a gilded Parisian designers’ salon for whom extravagance was as quotidian a thing for most as tying one’s shoes. Opening Friday, Oct. 23, 6:30 p.m.