An advanced method of imaging is to use the model display mode. Most users focus on capturing all the data and forming a 3D model. This mode, lets you know what data is good and what data is bad or incomplete / unreliable. You image until all the red disappears from critical areas like margins and contact areas and is filled in with green. With a trained eye, all you look at is the live video feed in the bottom right corner and focus on the purple silhouette that forms on the object.
The purple silhouette is data or areas that is not being captured. Altering your angulation or your focal distance will mitigate the situation, and as long as your model is green in critical areas in the 3D model, and you can visualize clear and sharp margins, on the live feed, you know you will have impeccable results.