The inventory of the collection gives us the artists' index whose photographs are accessible in the online catalog.
It reflects the original arrangement given by Federico Zeri to his photo archive divided by centuries, geographic areas and artists.
The inventory indicates number and title of the box-files and of the related folders and the number of photographs in each of them.
At  present online:
138,596 painting pictures up to 18th century 
3,112 sculpture pictures from 11th to 20th centuries
868 battles pictures
216 trompe-l'oeil and anamosphosis pictures 
The online database is constantly increased with new cataloged photographs.