Node Gallery also supports displaying small preview pictures, a so-called microthumb or thumbnail navigator, of your photos instead of the default numeric pager. To do this, you have to install and enable the Node Gallery jCarousel module.

Node Gallery jCarousel is a module that combines Node Gallery with the jCarousel module to provide an out-of-the-box solution for paging through a gallery of nodes.
It uses Views to retrieve the images of a gallery and displays them using the jCarousel module. The module contains a predefined view along with some CSS and theming to provide a site administrator an easy way to give his/her users more flexibility when paging through image nodes. The pager uses AJAX, so no matter how big your gallery is, the carousel will only need to render at most an unordered list of 7 imagecache presets.