What are you useing to make your thumbs with ?? I use ACDSee and it makes pretty good 5 to 10 kb thumbs. I tried useing Adobe Photoshop but i had the same problums you did so i switched. Another thing to try is, start with a smaller image . If you try to thumb say a 2000 X 2000 image your thumbs going to be pretty bad. Reduce it to say 800X600 then thumb that one.