Front Page looks really dark

Hi,

My front page is currently in Masonry format. It looks really, really dark at the moment (as if some form of opaque filter has been applied over the top). When I hover over the second item in the page (i.e. with a two column format the second post in) the image goes brighter (as if the filter has been removed) but it does not do this for any other post on the front page.

I re-looked at the Tayp preview page and the same happens on this example website.

Is there anyway that this can be changed? I don’t know if perhaps it’s a colour setting?

Thanks!