Masonry Galerie – lightbox link & picture text

Hello,

I’d like to add a Masonry Galerie with text on the picture:

So far so good. But when I deactivate the lightbox link, the text on the picture is not centered anymore:

What can I do in order to have the text centered anytime?

AND is there an option to have the text centered on the picture when you activate the lightbox link and click on the pic? Now the text is on the bottom of the lightbox.

Thanks, Enrico