W&H: Καὶ ἦν ἤδη ὡσεὶ ὥρα ἕκτη καὶ σκότος ἐγένετο ἐφ’ ὅλην τὴν γῆν ἕως ὥρας ἐνάτης τοῦ ἡλίου ἐκλείποντος, ἐσχίσθη δὲ τὸ καταπέτασμα τοῦ ναοῦ μέσον.
RP Byz. Maj.: Ἦν δὲ ὡσεὶ ὥρα ἕκτη, καὶ σκότος ἐγένετο ἐφ’ ὅλην τὴν γῆν ἕως ὥρας ἐνάτης. Καὶ ἐσκοτίσθη ὁ ἥλιος, καὶ ἐσχίσθη τὸ καταπέτασμα τοῦ ναοῦ μέσον.
I think that all commentators are agreed that an eclipse is an impossible explanation here. But don’t Luke’s words τοῦ ἡλίου ἐκλείποντος mean “while/because the sun was eclipsed?” (I’m not sure if it’s genitive of cause, or an absolute, or of time.) Origen thinks that ἐκλείπει must mean eclipse and claims that it cannot be the original text for this reason.