Sunday, April 20, 2014

Who says that scorch from a hot metal template onto linen cannot be superficial at the thread level?

Answer to question in title: the same individual who claimed that faint scorches cannot be enhanced, as per Turin Shroud image, with 3D image enhancement software (e.g. ImageJ, see previous posting). The claim is quite simply false?  How do I know?

I'm in Switzerland right now, away from home, away from my scorch kit, microscope etc. But I did bring some scorched linen with me, intending to tease it apart at leisure with needles to explore closely the depth of penetration of scorches into the bundles of fibres. Having just done that, using a pair of needles to extract single threads from the (quite heavily) scorched  areas of weave, and then using the same needles to tease apart those threads, I  can tell you this with absolute confidence, dear reader. That highly visible scorching is confined to just a few surface fibres (of which there are scores) in each linen thread. Put another way, it's a minority of fibres in scorched threads that are scorched. What's more, the naked eye alone is sufficient to arrive at that conclusion. One does not need a microscope to distinguish between scorched and unscorched fibres.

In fact, I suspect that it is uncritical examination of photomicrographs that has led to the wrong conclusion. It is all too easy to be fooled by in situ photographs . One has to tease the threads apart, separating individual fibres,  to be certain that patches of yellow colour really are there in cross-section, as distinct from being reflected or refracted light from surface scorched fibres.

Take away message: Scorches that are superficial at the fibre level can be superficial at the thread level too, and indeed are in my  linen specimens, even quite heavily scorched ones. Beware of claims to the contrary. Ask to see teased out fibres.

This is a holding reply needless to say. I'll try to give more details once I'm reunited with my experimental gear.

Colin Berry

Shores of Lake Geneva with splendid views across to French Alps

20th April 2014

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