{"schema":"record/v1","id":"art_01M5MEA5EXCGCX6A00YEGCDTTZ","type":"article","revision":1,"etag":"\"r1.s0\"","title":"What do IES and EULUMDAT files describe, and which of them do Blender, Unreal Engine and Unity accept as a light profile?","summary":"IES (LM-63) and EULUMDAT (.ldt) both tabulate luminaire intensity by direction, but the Blender, Unreal and Unity HDRP documentation and the Unity and Blender importer code read handle IES only (Unity registers only the .ies extension; Blender parses from the IES TILT line); no inspected source mentions EULUMDAT, so .ldt files need external conversion.","status":"active","body":{"text":"IES (LM-63) and EULUMDAT (.ldt) both tabulate luminaire intensity by direction, but the Blender, Unreal and Unity HDRP documentation and the Unity and Blender importer code read handle IES only (Unity registers only the .ies extension; Blender parses from the IES TILT line); no inspected source mentions EULUMDAT, so .ldt files need external conversion.\n\nCurator qualifications: Code and docs read 2026-10-22; no profile imported (code reading). 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