 The major disadvantage of the panoramic is that it may be impractical to reach the center of the item (enclosed pipe) or the source may be too weak to perform in this arrangement (large vessels or tanks).The second SWE/SWV arrangement is an interior placement of the source in an enclosed inspection item without having the source centered up.The source does not come in direct contact with the item, but is placed a distance away, depending on client requirements.