Blog Image/icon Being Resized To 304 X 890 ?

So I am creating some new blog articles and want just a small icon added so it shows in the widget on other pages. But it makes it huge putting loads of whitespace around it?


I have just read on here where some of this code is and removed the sizing specification for the image and then manually re-edited the image - but how do you stop it from resizing it if at all possible when using the admin?

Would be good if there was a check box to have it only appear as an icon in the widget.