Change Image Size on Post?

Is there (or can there be added) an easy way to scale down the image size on the actual post? See the page on my web site at http://www.logicaloperators.com/Community/Blogs/Post/3440/Logical-Operators-Turns-25 for an example.

I specified a downloaded image of size 800x632 for the post. This image seems to scale down appropriately for the post summary on the main Blogs page at http://www.logicaloperators.com/Community/Blogs, but on the actual post page, the image is increased in size (and it appears, ratio also, since the new image is 1140x400) to fill the entire screen width, causing it to spill over into other content.

The images for other posts on the same blog also have the same issue, although I don't think we had those issues before upgrading to Blog v6.4.0 and moving from the v6 skin to the new Default skin.

Ideally, I'd like to see the image scale down (keeping aspect ratio) to fit within the same width that the text of the post uses.

Currently using a Bootstrap3 compatible skin, DNN 8.0.4, Blog Module v6.4.1, Blog Default skin.

Thanks in advance for any help!