And, as Assemat-Tessandier points out, the newly published infrared
reflectogram of Maternal Affection reveals a number of artist changes, including a reduction in the size of the head of the central seated woman.
The typical output of a TDR measurement is a
reflectogram, which displays the reflection coefficient ([rho]) of the system under test as a function of the apparent distance ([d.sup.app]).
Another way to increase the energy is to use pulse compression [15], this is done by injecting a binary pseudo random signal [16] and calculating the correlation of the measured signal with the injected one to obtain the
reflectogram. The idea of linking TDR and spread spectrum techniques led to novel methods using pseudo random binary sequences [17] as test signals, later refined as Sequence Time Domain Reflectometry (STDR [18]) and Spread Spectrum TDR (SSTDR [19, 20]).
In presence of a water leak, there will be a local change of the dielectric characteristics of the soil (in fact, water has a high relative dielectric permittivity with respect to soil); therefore, in correspondence of a leak, there will be a change of the
reflectogram (generally, a relative minimum is observed).
reflectogram, run from the bottom right of Two Venetian Women to
The infrared
reflectogram (Figure 2) revealed that the current landscape was painted over a previous portrait.
There are also two modern forensic studies of the painting, an X-ray and an infra-red
reflectogram, which reveal various changes Degas made while working on the canvas, mostly to do with that troublesome architecture rather than the figure.
If only a single impairment is affecting a loop and close to the GO, a good case can be made for automated analysis of the
reflectogram. However, "...conventional metallic TDRs are not capable of detecting all echoes.
The infra-red
reflectogram, which was displayed next to the picture in the first half of the year, is nowhere to be seen.
These works are also 'backed' (literally installed behind the screens on which the pictures are hung) by highly informative X-ray and
reflectogram evidence.
The realistic mode of these representations is described in detail (including the use of infrared
reflectograms of some underdrawings).
The volume make a stylistic comparison of the underdrawing revealed in infrared
reflectograms of early Netherlandish paintings with the paintings themselves when that is possible.