I have images in an album that were generated at the same second (for example: 13:31:42) as I was doing continuous (rapid/speed) shooting. The images that were shot in the same second aren't being sorted correctly because of this.

This isn't zenphoto's fault, you'd think that a camera that can shoot multiple images per second would record the milliseconds in the EXIF data, but there's no work around for that.

Is it possible to have a second sort option in zenphoto, like sort by date,title or another value?

I have a temporary workaround. In the table 'znp_albums' I set 'sort_type' to 'Date,Filename' for the album in question. The images are now sorted properly.

This will be blown away as soon as I edit the options for the album though, it will change the sort order to "" ('parent album image sort order', the default).

I'm still trying to make sense of the php files for zenphoto, to fix it 'permanently'.

I updated the following in 'zp-core/admin-functions.php':

$sortby = array(gettext('Filename') => 'Filename', gettext('Date') => 'Date', gettext('Title') => 'Title', gettext('ID') => 'ID', gettext('Filemtime') => 'mtime', gettext('Date,Filename') => 'Date,Filename' );