Even though I try to feature images with high quality, when these images are shown all together in the homepage they appear blurry. The effect goes away when you visit a particular post, then the image shows with high definition. I guess the theme automatically compresses the images so that the homepage does not take ages to load.
However, as you can see at cranfield.org, the result is a miserable homepage. Is there any way to control the compression that the theme applies when showing several posts all together?
No need to apologize :) Most themes actually create a custom image sizes, so usually you don’t need to tweak the WordPress media size options. But I tend to keep my themes lean and easy on server resources, so I simply use what WordPress offer out of the box wherever possible. Just to explain ;)