First, all the test really tells you is the proportion of Carbon-14 to Carbon-12 in the sample.
That's all.
To assign a date to that ratio, several other assumptions must be made. Foremost, on must assume the sample is a valid representation of the object to be dated, and has not been contaminated with material from different time periods.
Second, too many other puzzles remained to glibly assign a medieval date. If that were the case, how was the image formed? All research indicates the image is due to a reductive chemical reaction with odd characteristics, such as being a surface effect, and with the shading due not to the intensity of the reaction, but to the density of affected fibers. Furthermore the image contains 3-D depth information, and strangely is a "negative". No good explanation of a process to recreate all those characteristics has been discovered, except to note it is similar to a photographic technique -- hundreds of years before photography.
Now the NY Times is reporting that guess what, the sample used for the carbon date was indeed from the wrong part of the shroud -- it is from the part that is known to have been patched with medieval cloth to repair fire damage, and to add a backing:
The Shroud of Turin is much older than the medieval date that modern science has affixed to it and could be old enough to have been the burial wrapping of Jesus, a new analysis concludes.I've been following these studies for a long time, and the STURP science team that studied the shroud in the 1970s was composed of real scientists -- not cranks -- and they were not religiously motivated. See for example this site. As I write, this former STURP member was just on Fox News!
Since 1988, most scientists have confidently concluded that it was the work of a medieval artist, because carbon dating had placed the production of the fabric between 1260 and 1390.
In an article this month in the journal Thermochimica Acta, Dr. Raymond N. Rogers, a chemist retired from Los Alamos National Laboratory, said the carbon dating test was valid but that the piece tested was about the size of a postage stamp and came from a portion that had been patched.
"We're darned sure that part of the cloth was not original Shroud of Turin cloth," he said, adding that threads from the main part of the shroud were pure linen, which is spun from flax.
The threads in the patched portion contained cotton as well and had been dyed to match.
From other tests, he estimated that the shroud was between 1,300 and 3,000 years old.
One thing is certain: it is NOT painted!
Not to mention that artistically, it doesn't fit at all with the style of iconography of the period.
As a medieval creation, it is even more of a mystery than assuming it is somehow an authentically transferred image (by means unknown) of an actual person buried in the 1st century AD!
In addition, there is an interesting historical theory that "fills in" the gap between the time of Christ and the time it surfaces in the historical record for certain in the 14th century, if it is associated with the "Mandylion" cloth of Constantinople (since vanished), assuming it was folded up to show only the face -- and is thus possibly the source of the "Veronica's Veil" legend, with the name "Veronica" being a corruption of the term "Vera Icon", or "True Image". It might also then be the source of the ideas behind the Holy Grail stories. And this theory explains why early Christian imagery portrayed Christ in many different guises for a few hundred years, until suddenly "converging" on the popular conception (being very similar to the image on the shroud), if the shroud, as the Mandylion, was eventually put on display in Constantinople, and became the common "touchstone" of artists to imitate...until it was taken in the Crusades by the Templars. It also could have served as the source of some of the politically-motivated charges of heresy against the Order, claiming (among other things) they worshipped a bloody head.
Of course, just proving the cloth itself is old enough doesn't prove anything other than it's not obviously a fake. But it surely cannot simply be dismissed, and remains a source of intrigue, inspiration, and wonder.
