Shading on Polaroid caption?

The plug in installed perfectly and is working well. I was hoping you could tell me how to avoid the shading that’s appearing on the bottom “caption” portion of the photo when it’s enlarged into the lightbox? Thanks!

You can see it in the screen capture here:
https://www.teamcorcoran.com/prom/wp-content/uploads/2013/01/Screen-Shot-2013-01-21-at-11.45.55-PM.png

thank you –

https://www.ads-software.com/extend/plugins/polaroid-gallery/