Email Standards Project Acid Test | Email Standards Project

http://www.email-standards.org/acid-test/

Photo.net - Jpeg Compression by Gordon Richardson - photo.net

This site has great visuals that will help you explain the visual difference
between a high quality jpeg and a low quality jpeg. HINT: Click on the "Jpeg
Quality Settings" link at the top of the article.

http://photo.net/learn/jpeg/index.html#qual

Let me know if this helps.
Thanks,
Sarah