Source: https://www.lpi.usra.edu/resources/apollo/frame/?AS15-99-13488

Here is the part of the Apollo 15 flight journal that relates to the UV image sequence:

247:43:20 Worden: Roger. Omni Delta.

[Very long comm break.]

[Having moved to the UV photo attitude, omni antenna D is best placed for communication with Earth.]

[Ultraviolet photographs are taken out of window 5 because it is constructed from quartz which transmits UV. A Hasselblad camera is fitted with a specialised 105-mm lens whose elements are likewise transparent to UV. Magazine N is used for this photography. The spacecraft is allowed to stabilise for 5 minutes with the FDAI set to its maximum sensitivity. Once stable, and in a change to the original procedure, the CMC mode switch is set to "Free" to inhibit further firing of the RCS thrusters, giving the crew a steady platform from which they can conduct the photography.]

[Eight frames are taken in all, two through each of four filters, though only seven appear in the Apollo 15 Index of 70-mm Photography, AS-15-99-13476 to AS15-99-13482. The proximity of the Sun to the camera's field of view is apparent in frame AS15-99-13478, taken through filter 2 with the Earth only dimly visible as a faint crescent in the central iris reflection. The linear marks to the lower right are cause by reflections from wipe marks on the window after someone has tried to clean the pane. A clearer image of Earth is in frame 13482, taken through filter 4.]

[Though an additional photo is to be taken through the same combination using colour magazine P, this magazine was exhausted in lunar orbit. Some colour photos of Earth were taken during the trans-Earth coast on magazine Q but they do not relate to this sequence of UV photos.]

[Afterwards, a protective cover is placed over window 5 and spacecraft attitude control is returned to the computer by placing the CMC switch to "Auto".]