"Here is an image of that gallery
in the Vatican
from my collection.
This photo is possibly by
The date is somewhere between
1860 and 1878.
The original photo was taken
from a greater distance from the central seated figure than
the Macpherson, therefore the detail is not as good as the
Macpherson after you enlarge it.
The photograph, possibly by
Alnari, however, does
take advantage of the
natural lighting to produce an almost chiaroscuro effect
when looking at the total assemblage of sculptures."
Douglas Olcott, Berkeley, California, USA.