Logo can also contain just initials "DN" instead of the full name.
Logo with a graphic could incorporate the initials "DN" or just the
"D", or possibly just an image that is film/movie/entertainment
related.
Logo should also work as a watermark on photos. Simple but stands
out.
I like the leica, and zeiss logo, potentially the
logos from film festivals or wards, frame lines from a rangefinder or
camera, exploded view of lenses, light meter or cameras, but am not
married to any of those design ideas.
If you use fonts that require a license, confirm with the client they're ok with it. For licensing reasons, it is better to provide your client with information on how to acquire the font rather than providing the actual files.