Remove image overlay from post grid items

My featured images on The post grid plugin look good, except that they have an overlay. It lists on the plugin features that there is ‘Image overlay control’. Could you please let me know how it can be done. I am using the hover grid option. Tried many ways to do it, but featured images appear dull due to the overlay and I would like to remove it.

• This topic was modified 2 years, 10 months ago by bl v.