It can be most simple than we are wondering. There are two points to achieve which you want: Set up a View (to show the images which are custom fields) and use a Lightbox plugin just to achieve this effect (perhaps: wordpress.org/plugins/wp-jquery-lightbox).
You will need to customize the Meta HTML section of the View to display the Lightbox parameter properly. The full code seems with:
[wpv-layout-start]
[wpv-posts-found]
<!-- wpv-loop-start -->
<ul>
<wpv-loop>
<li><a href="[types field="my_image" raw="true"]" rel="lightbox[roadtrip]">[types field="my_image"]</a></li>
</wpv-loop>
</ul>
<!-- wpv-loop-end -->
[/wpv-posts-found]
[wpv-no-posts-found][wpml-string context="wpv-views"]<strong>No posts found</strong>[/wpml-string][/wpv-no-posts-found]
[wpv-layout-end]
Please let me know if you are satisfied with my answer and if I can help you with any other questions you might have.