Sampling, artifacts radial

The best results in this study were obtained with the Norsodyne resin, which is currently used for artifact treatment. No cracks were observed on treated samples that presented a hard surface. However, radial cracking occurred with cylindrical forms. The mean shrinkages in the longitudinal (/), radial (r), and tangential (t) directions were, respectively for beech samples, 0.9% (/), 2.3 % (r), and 4.6% (t) for oak samples, 0% (Z), 0.9% (r), and 1.2% (t). As far as highly deteriorated wood is concerned, some warping can be expected. 

Notably, both radial and LCRS schemes can be considered as special cases of the spiral sampling scheme. PSF of this distribution is the combination of the two above PSFs. The artifacts form ring-shaped ridges, but the intensity is not constant along the rings, but varies with angle (see Fig. 6f) [60]. 

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