[Plugin: Photo Gallery] Poor Thumbnail Quality

Hi, I need some assistance with this. I downloaded the Photo Gallery Plugin to make a portfolio page but the thumbnail quality sucks.I downloaded the Regenerate Thumbnails plugin but I can only apply it to my Media gallery not the gallery I set up with a Photo Gallery plugin. So how do I fix the quality of those thumbnails? re-sizing thumbnails didn`t help, Compression is at 85%. Can it be fixed or should I just try another plugin for this? Thanks!!

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