The Library of Congress Online Catalog is the primary tool to access the bibliographic records for the Ottoman Turkish collections. A good way to start is with a Keyword search using a subject such as "Turkey--History--Ottoman Empire, 1288-1918" and limit to language "Turkish, Ottoman." Titles and authors may be searched using their Romanized form. The Ottoman Turkish Romanization table (PDF, 166 KB) provides consistent spellings for these titles and names.
You may search for Ottoman Photographs using the Prints & Photographs Online Catalog (PPOC) and entering subjects such as "Ottoman empire". Select the Abdul-Hamid II collection of photographs of the Ottoman Empire link to view the entire collection.
Alternatively, on the Prints & Photographs Online Catalog (PPOC) landing page, below the search box and featured collections, you may select the Abdul-Hamid II collection at the top of the list of All Collections to search within the Abdul-Hamid II collection. For example, you can search for keywords women education.