I don’t think there’s any room for doubt that the Shroud is authentic.
Ever since 1898, when it was discovered that the image is a negative, there has been no room for theories that the image was “painted” by any human hand.
Now we know that the image is really made up of distance information—i.e., the shade of the image at any given spot corresponds to a distance between the body and the cloth.
It does not require faith to believe that the Shroud is the burial cloth of Christ, and that it is evidence of the Resurrection. It requires only intellectual honesty.
Dr. John Jackson, one of the members of the 1978 Shroud of Turin Research Project (STURP) study is a friend of mine. STURP was the very first scientific study of the Shroud.
http://www.youtube.com/watch?v=zdKGV4SMpKY
https://www.youtube.com/watch?v=5ZgTstKXb7Y&feature=player_embedded