You may improve the image with a high speed shutter. Many video cameras
have variable speed shutters. One is typically not aware of the
blurring of images when watching video at 30 fps but for digital
purposes you look at each individual frame. Since you are looking at a
snapshot of a rapidly moving object you need to limit the amount of
movement while the shutter is open. You may need enhance lighting
conditions also.
I write:
Thanks, Jerry. Trust me to overlook the first thing one should check. You need
a camera with an (electronic) shutter speed that is at least as fast as 1 ms.
Ours can do 0.1 ms, but that doesn't seem to be necessary for any of the
experiments we do and requires brighter lighting to get good images.