I've gotten some really great feedback about my Two-Inch Stop Exercise post from last week. The coolest comment came from the president of the American Viola Society, Kathryn Steely, who asked me to edit the post into a format to share on the AVS Teacher's Toolbox! That is exciting and edits are in the works! I had one of my students take a few photos, but am not too thrilled with how one of them came out, so will have to redo them. In the meantime, here are two photos to help you or your students visualize the shapes created when drawing a straight bow.
As you can see in the photo above, I have ridiculously long arms. For most people, when they are at the tip, their right arm is straight, without the curve I still have at my elbow, which will create a more accurate triangle than what you see above. Perhaps I should commission a bow maker to make an extra long bow, just for me? ;) Notice the shape created when the bow is parallel to the bridge-- a large triangle!
In this photo, I am at the frog. Notice the small triangle created by the two parts of my arm and my viola.
In the next picture, I've placed the two preceding photos side by side. You can see that the "top" line of the triangle (from shoulder to sounding point) stays pretty much the same. What changes is the arm. When at the frog, your upper arm is in front of your body. As you initiate the down bow from the frog, the upper arm opens towards your right side. At approximately the half-way point in the bow, the upper arm will be parallel to the bow (which will create the square, as can be seen in the original post). From there, the upper arm stops moving, and the lower arm continues to open, until the arm is straight and the large triangle is formed.
So if you look at the side-by-side photos, you can se that the angle of my upper arm changes from tip to frog. That can be a very helpful visual when learning to play with a straight bow!
Let me know if you have any questions or comments. I'll post better photos soon.