Taking photos of blind people

Hey there dpreview community!

As it turns out, this weekend i'll be covering a wedding in which the couple is partially bling/have serious problems with their sight. They have also told me, that some of the guests they invited cannot see at all... Delicate situation.

Have any you encountered such or similar shooting situation?

I would like to ask you for some tips and tricks regarding setting up group portaits, giving them directions on how to stand and look, taking photos of the couple seperately, taking off or leaving on the sunglasses, the white cane..., lighting options eventually. Any help whatsoever is appreciated!

Thanks!