Hi, could someone help me answer this question.
When I create a field of type "image" in the bottom can see several options for creating the "Thumbmail" but is not that's the difference between "Resize" and "Resize (Dynamic)" ... In that lies the difference?
I believe that if you use Resize (Dynamic), it ensures that the image ratio remains the same. So, instead of distorting your image to meet the width and height you enter, I think it does the max fit within the parameters you provide keeping the ratio constant.