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Apollo 8 Hasselblad image from film magazine 12/D - Lunar Orbit. This photo was used in Figure 2-6 (b) of the Analysis of Apollo 8 Photography and Visual Observations (SP-201), which has the following caption:

Comparison of photography of same area (13° S, 157° E) on the lunar far side. (a) Portion of Lunar Orbiter II frame H-75 (Sun angle 19°); (b) Apollo 8 frame 2100-D (Sun angle 51.5°).

The text of the Analysis refers to the figure as follows:

One of the most important aspects of the Apollo 8 photography is the acquisition of high-resolution photographs under high-illumination conditions. For the first time, it is possible to compare topographic features photographed by Lunar Orbiter under relatively low lighting conditions (phase angle of approximately 20°) with the same features photographed by Apollo 8 under high lighting conditions (phase angles greater than or equal to 50°) and with approximately the same resolution.

Figures 2-5 to 2-8 are pairs of Lunar Orbiter and Apollo 8 photographs of the same areas taken under different lighting conditions. The Lunar Orbiter photographs were all taken at a relatively constant Sun angle of approximately 20° from the horizontal, while the Apollo 8 frames record Sun angles varying from 34° to 77°. As the Sun angle becomes greater, differences in albedo become more apparent. On the Apollo 8 photograph in figure 2-5(b), albedo differences are just beginning to appear at a phase angle of 34°, and it is still easy to recognize topographic features by their shadows. At the higher phase angles (51°, 62°, and 77°), shown respectively in figures 2-6(b), 2-7(b), and 2-8(b), the albedo differences are readily apparent; but it becomes considerably more difficult to recognize elevation differences because of the lack of shadows.