Okay - now that I read the article....
I think that the absence of gravity when the image was laid down would explain the article quite a bit. “No consistent pattern...”
Interesting comment though about if the body was cleaned - why was there any blood at all on the image? Although I’m guessing those wounds weren’t going to heal up after the person was dead - and I don’t think the spear wound caused him to bleed out.
From Luke 23
52 This man went unto Pilate, and begged the body of Jesus.
53 And he took it down, and wrapped it in linen, and laid it in a sepulchre that was hewn in stone, wherein never man before was laid.
54 And that day was the preparation, and the sabbath drew on.
55 And the women also, which came with him from Galilee, followed after, and beheld the sepulchre, and how his body was laid.
56 And they returned, and prepared spices and ointments; and rested the sabbath day according to the commandment.
I don't think much bleeding happens after death. Once the heart stops, the blood pools in the lowest part of the body, normally the back, buttocks, and whatever part of the arms and legs are lowest. I think the blood coagulates after pooling.
It's gruesome, I know.
As skr pointed out, the body wasn’t washed. It was placed in a grave quickly to be done before sundown (which marked the start of the Sabbath.) The women were on their way to prepare the body for burial when they discovered the empty tomb.