Hero images for posts

Hi all,

Is there a way to add a ‘hero image’ for posts? By that I mean an image that is attached to the post itself so when I loop through them, I can display the full image alongside the post excerpts.

I understand that you can upload any images into the post itself, by I want to be able to display only the post excerpts on the homepage with the ability to show that main image for the post in its full size and separate from the post contents, so that I can create a two column layout for the post lists – one for the image and the other for the excerpt.

Hope that makes sense.