Comparative analysis of two diffraction schemes for widely divergent beam of $\mathrm{X}$-ray radiation

Comparative analysis of two diffraction schemes $d-c$ (diaphragm-crystal) and $c-d$ (crystal-diaphragm) for widely divergent beam of $\mathrm{X}$-ray radiation is conducted. It is justified that in $c-d$ scheme the diffraction image is a topographic map of the studied area of the crystal.