My Society is using Zenphoto to archive and display historical photographs: https://rchsimagearchive.org.uk/
I have been advised that, for copyright reasons, it would be very desirable to hide some of the photos, but display their Titles and Descriptions. That way, site visitors would know that we have preserved all of the photos, but that some are not published because of copyright concerns. They should then be able to contact us to ask for a private copy of the photo.
I realise this has been requested previously, but the copyright issue is making it more important.
By the way, is it possible to have a page on this website listing the enhancements that have been requested, and those which are likely to be implemented?

Password protect the images in question to achieve this. Also use an external albums folder as otherwise people may be able to guess the path to the actual image from the image page url. Perhaps use htaccess to block direct access additionally.

Other option is to use a specific tag and add a switch to the theme pages where needed to "block" the image but display the title and description. This is not anything we will implement as this is a specific use case to be solved with custom theme coding.

The page about features are the tickets on the GitHub repository. However that is not complete as we are working on other stuff ("next major release").