The Berlin-Brandenburg Academy's own Abklatscharchiv catalog states that Karl Richard Lepsius's 1842–1845 Egypt expedition produced 517 'Abklatsch-Serien' (paper-impression series), citing Lepsius's own expedition inventory by name

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The Berlin-Brandenburg Academy of Sciences (BBAW), custodian of Karl Richard Lepsius's own expedition papers, states directly: "Nach dem 'Verzeichnis der während der Reise des Professors Lepsius gesammelten Monumente, Papierabdrücke, Zeichnungen etc. 1842-1845' wurden während der Ägypten-Expedition insgesamt 517 Abklatsch-Serien angefertigt, die später in Berlin in über 100 großformatige (72 x 56 x 7 cm), bücherförmige Kästen lose eingelegt wurden." (According to the "Register of the monuments, paper impressions, drawings etc. collected during Professor Lepsius's journey, 1842–1845," a total of 517 Abklatsch series were made during the Egypt expedition, later placed loosely in more than 100 large-format, book-shaped boxes in Berlin.) The BBAW traces the numbering precisely: series 1 was taken 14 September 1842 (a small statue of Nefer-abu, in Malta); series 517, the last taken in Egypt, was made 7–14 June 1845 at the Amarna rock tombs on the return journey.

A "series" bundles all sheets documenting one monument — from a single sheet to roughly 100 for a whole tomb wall — so 517 is a count of documented objects, not individual sheets. It is not directly comparable to the widely-repeated "~6,000 squeezes" figure (attributed to Christian E. Loeben's Oxford Handbook chapter, still unconfirmed against a direct read as of this session) without an average sheets-per-series ratio, so the two figures may not actually conflict.