Hiding Image Captions and SEO - WEXLEY

Site URL: http://www.macneill.photography

I'm using Wexley to host my photography site.

Photographers' biggest problem with SEO is the relative lack of copy/text for Google to bite on. So images titles or captions are essential IMHO.

But I'd prefer if they were hidden (and only visible with 'hover over' in the lightbox). 

So my question is this: Will hiding the caption effect my SEO? 

Thanks.