Archery videos
These movies were shot as training aids in 1997 and 1998 by Francis Parchaso
in his back yard in San Francisco. Video is a very revealing medium; it is
worth planning a video session to make sure you have shots that are useful.
Close-ups of loose, bow-hand, and alignment are especially useful, but make
sure you have some all-over shots too. Make sure you take the video using a
tripod, otherwise you may not be able to see body position changes or weight
shifting. I've added criticisms of my form based on the video sessions.
These videos were captured at 15 frames per second, and have been converted
to MPEG format. The clips are about 2-4 seconds long. You'll need an MPEG
viewer to watch them, however I can't recommend any good ones. The commercial
viewer that I use has a dreadful user interface and very few features, and
I've not come across any good free viewers.
The first video is an older shot from the front (915K MPEG). This shows off
my central string alignment. In the frame before the arrow is loosed, body
relaxation is seen, which causes a fractional collapse before the arrow is
loosed. The good points evident are the simplicity of the shot and the
initial straight bow reaction.
If you can single step through videos, have a look for the frame
shown in the thumbnail, which is the only one on all the video we shot that
caught the arrow in flight.
A later video from the
same viewpoint (albeit with the video camera not zoomed as much) did not
show the same collapsing tendency.
The next shot is from the side (456K MPEG). This shows a great improvement
over an older video. My spine is straight after the shot,
indicating that the shot is far better balanced. My
rear elbow does not change position as much while moving into the anchor
point, although this is still a flaw to work on.
The apparent horrendous forward loose is an artifact of the frame grabber,
which had a pixel-shift glitch at that frame.
This old video from above (402K MPEG) shows that the rear elbow is not quite in
line, and the slight sideways reaction of the bow may show some torque in the
bow-hand (the frame after the loose shows the reaction straight, though). I
did not repeat this shot in any later video session, so I do not have
material for comparison.
I believe that the slight stall and forward motion of the clicker in this
old shot of my bow hand (501K MPEG) is before I reach my alignment point. The
motion after that is continuous. The bow reaction is forward and the hand
doesn't drop too much.
The amount of time between the clicker going and the loose is surprising;
there are three clear frames between the clicker and the arrow motion,
equivalent to one fifth of a second.
A more recent video shows the bow hand dropping alarmingly; this may be
a frame grabber artifact, but some of the other videos from the same
session also show a lot of front hand motion after the shot. This is a
problem I will be working on.
This shot from behind (444K MPEG) is not very instructive; the rear shoulder
motion at the loose is shown aligned on the rear half of the rigid-frame
plane (the shoulder-elbow-anchor and anchor-bowhand-front shoulder plane, as
described in Richard Carella's ``Front Shoulder Blade/Rear Shoulder Blade
Techniques and the Rigid Formaster'' paper).
My loose is much cleaner in this video (524K MPEG) than a previous video of my
loose.
There is still perhaps a slight tendency to reach my head towards the string,
but the rear shoulder motion shows that the same upper back muscles are being
used all the way through the draw and shot.
The last video was taken to show the back muscles working (588K MPEG). This
video shows the difference that archery-specific weight-training can make.
Compared to a previous shot my muscle definition is much better.
Comparison also shows that my spine now stays straighter, balancing the
shot, and the use of the upper back muscles is improved. There is still a
slight alteration in muscle direction evident as the shot settles into the
alignment position. The front shoulder position is good, staying low
throughout the shot.
Last modified on 12th February 2004 by angus@harlequin.com