Long-eared Owl attacking Osprey

On 6th April, the Dyfi Osprey Project nest camera picked up several attacks by an owl on Telyn, the resident female Osprey, on the perch by the nest. Most comments following views of the footage assumed this was a Barn Owl - a regular visitor to the reserve. But close attention to the underwing (see https://www.facebook.com/watch/?v=874095486503045 - especially the attack in slow-mo, shown after the full speed one) shows a short black line on the underwing, but no black tip to the wing. This combination rules out both Tawny and Short-eared Owls, while Barn Owls have a pure white underwing. Further attacks came on 10th April. So, a brilliant record - though Telyn might not agree. Thanks to Emyr Evans for posting the video, and to Iolo Williams for identification input.