Board Thread:General Discussion/@comment-27121579-20151030110310/@comment-4010415-20151114015509

It falls down, almost like it was tucked away under the mask.

And yeah, I think so too. It can probably be explained away in-universe as that being how she looked when she was Yang's age and the photo from the Volume 3 Opening is from when she was 21 (in her last year of Beacon, or right after graduating). We know that Yang has a photo of a woman (most likely her mother), considering she showed Junior a photo that she described as being a woman, and we could see the silhouette of a woman with long hair in her scroll. Maybe what she has is a really old photo from when Raven was younger, from before the Volume 3 Opening photo was taken.