I was supposed to obtain two images of the aorta, one using the harmonics feature and one without.  This first picture is the image that was obtained without using harmonics.  The aorta in this image has a lighter more grainy appearance.  In a way it blends with the surrounding structures more, making it harder to get a clear picture of the aorta by itself.  In the picture below where harmonics were used the aorta becomes darker and is more hypoechoic.  It makes the aorta stand out from its surrounding a bit better.  The harmonics also make everything posterior to the aorta much more hypoechoic as well.                 

       I am having a hard time choosing which picture I prefer.  The one with the harmonics does appear to make the aorta clearer and easier to focus on, but the one without seems to make the overall picture more pleasing to me. I suppose for diagnostic purposes the harmonics image would be better because you do get a clearer view of the aorta.