If I arrange for a photograph to be taken but get a friend to actually snap the picture, is she the copyright holder?
Depends on the circumstances under which you’re “arranging” for the photo. If it’s “here, take my picture in front of this pretty tree” then technically yes, she would own the copyright because she created the work. She can, however, immediately release the work into the public domain or she can give the copyright to you. If it’s “here take this photo so that I can publish it in my magazine” then the copyright status will be according to whatever the terms of her contract with you specifies.
That’s what I thought. I’d probably need to get her to assign the copyright to me.