I’ve been seeing a lot of complaints about image quality for the various sites. I take all screenshots with the game settings set on the highest settings using an AMD Radeon R9 390, but only the full size image can be viewed at 100% quality.
The 150 x 150 px Featured Images (thumbnails) are set at 80% quality. This is to decrease loading time for pages where there are hundreds of thumbnails. Those images are just a visual link to give you access to the post with the pictures. I do it this way so you have an idea of what you will see on the post (think of it as a preview) and whether it is worth your time to click on it. It was never intended for people to try to examine item details.
The post images (thumb) are also of a lower quality because I save them in jpg format (smaller file size) and they lose a bit as they are shrunk down to fit the page. Also, they are compressed when upon upload to save space.
Only the full size images (click on a post image to open it in a lightbox) are 100% quality.