Teaser of the Day (#3): Why many state that the Shroud is a 3D image

What is right or wrong with this material from page 9 of The Shroud: A Critical Summary of Observations, Data and Hypotheses, by Robert W. Siefker and Daniel S. Spicer.

Table I, Item 3.0:

The luminance distribution of both front and back images can be correlated to the clearances between the three-dimensional surface of the body and a covering cloth. This is why many state that the Shroud is a 3D image.

Scored: Established


imageThe variation in the image density has been analyzed mathematically to render a high resolution 3-dimensional body image.

While a photograph can be either a positive or a negative, there is no correlation in a photograph between the density of the imprint and the distance to the object. Uniquely, the image on the shroud appears denser in the areas where the vertical distance to the body from the cloth surface would logically be shorter. This allows the use of a simple mathematical function to recover the 3-dimensional information about the body. The 3-D characteristics present on the Shroud cannot be recovered with any normal reflected light photograph or painting.

As with the previous items, we are being forced to think of this only in terms of a cloth covering a body. While this may be the case, this is an assumption and not an image characteristic. It should be avoided.

A better way to describe this is to use accepted terminology from the world of three-dimensional graphics. The image is a height-field or height-map.

Smoke ring height fieldSmoke ring plotted as craterWith a VP8 Image Analyzer or newer computer software (POV Ray, ImageJ, etc.), the gray scale values at many xy points in the height-field to the left are plotted as elevation or terrain.

The software uses several variables including an altitude scale, a viewing angle and a virtual light source to enable us to visualize the shape.

Face as height fieldFace plottedThe same software with the same viewing angles and artificial lighting produces the apparent elevation in the face. This is true for the entire body of the man imaged on the Shroud of Turin.

It is important to note, as
Siefker and Spicer state, a normal photograph or a painting is a representation of reflected light as detected by a camera or perceived from an artists viewing position. 

There is no useful relationship between the gray scale values in a normal painting or photograph and spatial distance as found in height-fields.

imageVirtual reality and gaming software regularly uses similar height-field images (above left) to produce realistic landscapes. NASA uses them to generate 3D surface representations of the moon and planets. Those height-fields are created by radar and lasers. Google Earth software makes 3D renderings of our planet the same way. NOAA produces 3D images of hurricanes from radar data represented in height-fields. Height-fields are regularly used in new-generation 3D ultrasound sonograms.

Note: Height-field is a convenient term. Gray scale values found in such a dataset are applicable for both vertical and horizontal plots.

Here is an image I prepared using ImageJ. See: Do Your Own VP8-Like 3D Images of the Shroud of Turin

9 thoughts on “Teaser of the Day (#3): Why many state that the Shroud is a 3D image”

  1. If it is more appropiate to consider it as a height map, has it ever been analyzed throroughly fr om this perspective? I mean, for example the analysis of the variogram could shed light on many aspects.

  2. Gabriel, Wikipedia has a short write up on heightmap. It is worth a quick read at http://en.wikipedia.org/wiki/Heightmap . Heightmap is better than heightfield.

    The work you suggest needs to be done. Unfortunately the best images belong to the Archdiocese of Turin (12.8 billion-pixel HAL 9000 image) and aren’t available to the public or to those with the skill to do the work like Ray Schneider.

    And lets stop living in the past. The VP8 is not up to the work that needs to be done. Don’t get me wrong, what Jackson and Jumper did was amazing with what was available in 1976.

  3. If this is the shroud, then I’d like to know either, what have you done with the nose to flatten it out so thoroughly, or what has everybody else (including the VP8) done with the nose to make it so prominent?

  4. (1) As I understand it (e.g. Wilson’s description in “Turin Shroud” 1978) Jumper & Jackson draped a cloth over an Air Force colleague with a similar physique to the TSM. They then measured his cloth-body distance (normal or vertical??) and obtained an exact match with micro-densitometer readings on a true Shroud negative. I am under the impression that that is the fundamental experimental basis for asserting that the luminance provides an accurate 3-D height-map for the image. I imagine that more rigorous experiments may have been carried out since then with better equipment. However to obtain a true contour map, I should think that it would be necessary to add the height of the draped cloth at its various points, to the z coordinate. Although J & J seemed to think that there “was only one true way” of draping the cloth, clearly there’s some scope for variation in the height of the cloth. The bronze statue cast by sculptor Luigi E Mattei at the Pontifical Institute of Notre Dame of Jerusalem centre and shown on this site recently seems fairly persuasive evidence, even allowing for some artisitic licence. .

    (2) As Gabriel hints at above, the fact that there is this correlation between cloth-body distance and luminance, must say something about the image-forming process. I am thinking that if it is a chemical process for instance, then the gas(?) molecules as they are emitted from the body are perhaps inherently unstable, and in the time they take to arrive at the cloth are partly converted to their stable form with various concentrations depending on the distance they’ve traveled, resulting in the different intensities of luminance, and the consequential correlation with cloth-body distance. Does this make sense?

  5. Jumper and Jackson found that the VP8 image of the whole body was very unsatisfactory, looking distinctly “flat and stiff.” They made a full size physical replica of the VP8 image out of cardboard sheets, however, and by comparing its profile to that of a volunteer (in 18 places along the midline) they were able to derive the distortions to the x-y plane necessary for the z distances (derived from their intensity/cloth-body graph) to look more real. Draping a real cloth over a real body showed how similar their derived cloth was to possible actuality, but that part of their experiments was totally subjective. No measurements were made from the body of a volunteer to the surface of a cloth. It would be possible, I think, using a cloth of fine netting, through selected holes in which a thin probe, marked in millimetres, could be inserted, but to my knowledge this has never been done. Jumper and Jackson’s paper is an absolute model of scientific reticence and, as I said before, they are at pains to point out how far their results are from any ‘exact match.’ Here is an example of their meticulous prose: “These results demonstrate that the Shroud image has a 3-D characteristic in that image shading correlates with the distance between two surfaces, one of which can be interpreted as a body shape and the other as a cloth draping over that body shape.” Perfect.

    1. No need to use a probe etc. What is needed: a large scale 3D scanner. You scan the body laying down then drape it with a cloth and redo the scanning. So you get two scanned surfaces. You then measure thousands of distance body-cloth by measuring, using a computer, the distance between the two surfaces. That operation should be done for several draping.The caveat: 3D scanning of full body is expensive.

  6. I have just downloaded the original full paper by Jackson and Jumper of 1984 from my institution’s library. To my surprise, the widely extended idea that there is a correlation between cloth-body distance and image intensity is based on a very reduced sample: 13 measurement points only! The authors recognize this and state that 1700 points should be needed to clearly establish a mathematical model describing the exact nature of the relationship between distance and intensity of the image. While the fact that the image shows 3D properties clearly indicates that some kind of relationship exists and intensity attenuation of the image takes place (no doubt at this point), the exact nature of this relationship may represent an important step forward because some mechanisms (energetic fields, radiation, diffusion, laminar flow) and their change with distance, exhibit very particular mathematical profiles. Really surprising that after so many years -to the best of my knowledge- no complementary research has been done in this line!

  7. the scorch theory might also account for the image intensity variation? if the cloth had been laid over a hot bas relief then the protruding elements like the nose could press more firmly into the cloth,compared to less protruding elements,therefore creating higher intensity image.

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