In the example used to illustrate the method (), the sample was placed at 60 cm from the detector. The corresponding scattering length was 200 nm. The sample consisted of three vials held in a light styrofoam frame. The styrofoam was found to be an effective X-ray scattering medium. The foam frame is conspicuous in the scattering image and not so in the absorption image.
In another test, the scan of an okra and a peanut at the scattering length of 200 nm show that the two objects have similar levels of absorption, but the peanut and particularly the shell have higher levels of scattering (). Pixels in these three parts form distinct clusters in the scattering versus absorption graph .
Scattering and absorption images of an okra and a peanut at the scattering length of 200 nm. (a) Absorption image. (b) Scattering image. (c) Pixel-wise scattering versus absorption plot of three different areas of the image.
In objects containing oriented structures, the level of scattering depends on the orientation of the structure relative to that of the linear grid. This is seen in a scan of two wood blocks placed perpendicular to each other (). The wood fiber of the horizontal block is aligned with the linear grid. The scattering length is 200 nm. In the absorption image , a diffraction pattern is visible in the horizontal block and it has slightly lower absorption than the vertical one (mean ± stdev of 0.087±0.006 versus 0.095±0.004, t-test for the significance of the difference between them gives P < 10−7). The horizontal block causes substantial scattering while the perpendicular one has minimal scattering  (0.168±0.062 versus 0.009±0.005, t-test for the significance of the difference between them gives P < 10−7).
Scattering and absorption images of two wood blocks arranged perpendicular to each other at the scattering length of 200 nm. Grid used in this experiment is aligned horizontally. (a) Absorption image. (b) Scattering image.
The scattering image may show structures that are not visible in the absorption image. In the images of a western cedar branch taken at 200 nm scattering length (), a bright central core running the length of the stem is visible in the scattering image but absent in the absorption image. This bright band corresponds to the pith of the stem [9
]. The pith is consisted of parenchyma cells with intercellular air spaces. The air spaces likely account for the higher level of X-ray scattering in the pith.
Absorption and scattering images of a western red cedar branch at the scattering length of 200 nm. Profiles across the stem are plotted in the insets. (a) Absorption image. (b) Scattering image.
The combination of absorption and scattering data can help distinguish different materials that appear similar in absorption images. In a scan of water and vegetable oil samples at 60 nm scattering length (), both have similar absorption and low levels of scattering. The two samples are separated in the scattering vs. absorption graph . In linear regression between the two measurements, the slope for water and oil are (fit ± standard error) 0.029 ± 0.001 and 0.018 ± 0.0005, respectively. These slopes are used to determine the fractional content of water and oil in each pixel. The absorption image can then be sectioned into a water image and an oil image .
Fig. 6 Absorption and scattering measurements of a vial of water (left) and vegetable oil (right) at the scattering length of 60 nm. (a) Absorption image. (b) Scattering image. (c) Pixel-wise scattering versus absorption plot of water and oil. (d) Water content (more ...)