Identify each image before building pages
HEIF is a container family that can organize image items and related information. A PDF is a sequence of pages. Determine whether the source is one photo, a group, or a sequence and make sure the intended images are represented in the document.
If several images belong in one record, define their order and page labels. A PDF can provide a straightforward reading sequence, but it does not preserve the original container's browsing or capture relationships. Keep the source file when those relationships matter.