Visually, the presentation and cycling of the images is pretty impressive. (But see below.)
I’d have to agree that the navigation needs to be much more obvious.
My initial reaction to the home page was “What is available here?” It wasn’t at all clear what content was available or how to get to it, so I quickly lost interest in the site.
To return to the cycling of images: I use the wheel on my mouse to scroll a page vertically, but on your site this doesn’t work as expected. Instead of scrolling the page up/down, it cycles through the images. I find this departure from normal behavior irritating so I’m unlikely to revisit the site.