I know that many sceptics have become believers as well. A quick search found a Mr. Barrie Schwortz, and expert with X-Ray imaging. And it sounds like one of the first to determine the 3-D aspect of the image.
Excerpt:
When it comes to testifying to this meeting point between faith and science, Schwortz is in a unique position: he has never converted to Christianity, but remains a practicing Jew. And this, he says, makes his witness as a scientist all the more credible.
“I think I serve God better this way, in my involvement in the Shroud, by being the last person in the world people would expect to be lecturing on what is, effectively, the ultimate Christian relic.”
“I think God in his infinite wisdom knew better than I did, and he put me there for a reason.”
My note: Schwortz also makes it clear that this is an image of a dead man. Believing it is the image of Jesus must be taken on faith.
I actually talked to him on the air. He strikes me as a good and decent man, smart too...