Sometimes the image quality for thumbnails is not as crisp, clear or vibrant as you might expect it to be. There are several things you can do to improve the quality of your thumbnails:
- Upload images with higher resolution. We sometimes see cases where images in the gallery are smaller than the thumb size set for the gallery. This will cause the images to upscale in the browser which will make them look blurry. Always make sure the image width is bigger than the width set in your gallery.
- Under FooGallery Settings -> Images tab, you can set the Thumbnail JPEG Quality to 90 or even 100. It is default to 80.
- For retina devices, make sure you have set your galleries to use 2x retina images. Under FooGallery Settings -> Images tab, set the Default Retina Support to 2x. Then click “Apply Defaults to all Galleries”, then click “Save Changes”. This will tell FooGallery to generate Retina thumbnails, which look a lot crisper on retina-ready devices.
If the above still does not give you the desired result, please check your server setup to see if the imagick PHP extension is installed on your server. Imagick is used under the hood by WordPress (if it is installed) with a fallback to the GD PHP extension. Imagick produces better quality resized images as compared to GD. You can read more about this here : Stack Overflow