What a conversation!
My 2cents say that it is real.
Well, that was before I learned about the shadowshroud experiment today, now I see a tiny sliver of hope tht it might not be real. However you may feel about the sturp group, there is one thing that they confirmed for sure and it is that it was definitely the image part of the shroud that was darkened (dehydrated!), and not the other way around, as it is the case with the shadowshroud experiments. The image is actually pixelated, it is made up of tiny dots, and their density defines the local darkness of the image.
What convinced me that the carbon dating had to be wrong is the fact that the linen of the cloth was bleached BEFORE weaving, which leaves an uneven criss-crossy pattern on the final product which is clearly visible and an undeniable fact about the shroud. This way of bleaching went EXTINCT in the 4th century, after which linen was always bleached AFTER weaving, which produced a more even colouring of the final product. No medieval forger could’ve known or would’ve cared about this detail, mouch less take the time to reproduce the old process of bleaching, which means that the supposed forger either used a 1000+ year old huge piece of unused linen cloth (in which case the carbon dating is wrong), or the image itself is is fourth century or earlier (because it is fused into the peculiarly bleached linen), in which case the carbon dating hasn’t got a whole lot to say about the date the image was made.
Counting carbon atoms however could go wrong, and in archeology it does happen from time to time, which is why it is a well-known practice in the field of archeology to disregard the carbon dating when other strong facts about the object in question disagree with the results of C-14 dating.