I call my one of LQS's. I arrange to use their hanging method, whatever it is, to hold my quilt. They don't mind as long as there isn't a class going on at the time.
I don't have to bother about sun and shadow ... and the LQS is very well lit. The display area is meant to show off the entire quilt to best advantage. After all, they want people to sign up for classes so they display many finished quilts and projects.
I just use my digital camera.
Otherwise, if I didn't have this available I would use a wall in one of my church's room, like the fellowship hall.
I do have a design wall that is 8' x 8' but prefer to hang my quilts to get pics.
ali