Blurry woocommerce product photos

Hi, First of, thanks for the beautiful theme, it does everything I want it to do so far. The one thing I am struggling with is the quality of the woocommerce product images (thumb, catalog and single product images). I have tried to regenerate thumbs using the plugin Regenerate Thumbnails by Alex Mills to various sizes (that I though would work based on the theme and the inspect within chrome browser). Is there a way to force it to load higher resolution images, or some css to control it? The most problematic ones seem to be the tall vertical banner images. It is tough to have such drastically different product image ratios to deal with. Thanks in advance for your help.

Brian

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