As the target comes into focus and the operator aligns the crosshairs, elements of the world slowly cease to exist until the only things left are the target and the operator's breath. As the rhythm of her respiration cycles -- breathe in, breathe out, pause; breathe in, breathe out, pause -- even her breath disappears into the target. When all is calm, the sound of the discharge echoes as a small puff of smoke reveals that the target has changed forever. The operator smiles, triumphant. Her mission is complete with no collateral damage: The finding is in place -- and the very expensive emerald next to it is unharmed. As with many bench operations in a goldsmith's day, the ability to successfully complete the task came down to one thing -- holding steady.
While steadiness comes naturally to some people, others have to work hard at achieving it. Your overall state of health and wellbeing contributes heavily to this ability, as do temporary factors such as stress and fatigue. But even under the most ideal conditions, there are things you can do to make yourself steadier. To find out more about this, I consulted my friend and nephew, Rob McCorkle, a retired lieutenant and sniper. The tips he shared with me apply whether you are shooting a high-powered rifle or a high-powered laser.
Macro and Micro Bracing
For a person behind a rifle, macro bracing usually involves a prone position in which the body is aligned straight with legs spread and feet fully contacting the ground. For a goldsmith behind a bench or laser, it probably means keeping both feet on the floor and your butt firmly in the seat with the small of your back up against the chair's backrest. This anchors your body and sets you up to work on micro bracing.
For a rifleman, micro bracing involves tiny movements in three dimensions: up and down, side to side, and twist. The operator of the typical jewelry workshop laser welder has to contend with all three of these dimensions plus another -- depth. Because you often hold your target freehand in the welding chamber and the laser beam's focus is contingent on keeping the target in sharp focus, you actually have to control four parameters, which is difficult under the best circumstances.
A relatively new innovation in the craft of shooting is the control of micro bracing by means of resting the rifle butt on a small sandbag gripped by the off-side hand. By squeezing the sandbag, the sniper can control and maintain incremental shifts in elevation. What I've found to be the most effective solution to micro bracing in the laser or when soldering is to find some way of bracing my hands together. Rather than having both hands free-floating within the laser chamber or while soldering at my metal bench, I find that if I simply touch some part (any really) of my hands together, I can achieve a stability otherwise unattainable.
To maximize muscle control when bracing, McCorkle suggests minimal muscle tension. In the goldsmith's case, there should be at least some pressure at the point where you micro brace your hands together. Holding a small amount of muscle tension in the braced position keeps your entire body working together and results in steadier hands.
With bracing in place, you should focus on your breathing, which moves most of your body rhythmically. The natural rhythm of the breath cycle involves a pause between breaths. A rifleman exploits this momentary period of quiet and times his shot to be taken during the natural respiratory pause -- a momentary period of no body movement. I would suggest the same strategy to the jeweler working at the laser -- especially for delicate jobs.
There is a spot in the center of the retina of the human eye called the fovea. Having the highest concentration of receptors and nerve cells, the fovea is the area with sharpest vision. To produce what we perceive as a relatively sharp field of vision, the human brain combines many images collected in a series of very rapid eye movements called saccades. These movements occur as rapidly as every 1/100 of a second and accumulate enough data for the brain to produce a mental image of a very widely focused field of vision.
Apparently, it is possible to train the eye away from the tendency to bounce around the field of vision, which can help to produce more consistent results in some applications. One example that has been studied is the act of putting in golf. Golfers who were trained to focus on one specific dimple on the ball rather than the whole ball reduced visual saccades to less than one degree of angle, increasing putting accuracy from about 60 to 85 percent. McCorkle suggests laser operators can improve the accuracy of their welds by using this technique to focus on just the target area of the weld, defocusing on everything else in the weld chamber.