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I wanted to see how my arrows were flying from my bow, specifically flight arrows.
A flight arrow presents a conundrum, you'd think you would want a nice stiff arrow to get maximum energy into the arrow, but you want a light point and small flights for minimum wind resistance.
This would mean the arrow kicks hard left as the string drives down the centre line of the bow and the arrow has to pass around the grip.
Of course this isn't an issue with a modern bow with a big cut out for the arrow to fly down as it is centre shot.
With a traditional wooden bow the arrow has to flex round the bow so you need a flexible arrow. The shot below is one of my regular arrows from "Twister" a Yew Primitive/neolithic style bow 45 pounds draw weight at 28" which shoots those arrows at about 165 feet per second.
I had been testing by seeing if the arrow struck the target square on at 10 yards. I found that I needed a much more flexible arrow than anticipated. For a 100pound draw weight I needed an arrow rated at 35-40 pound spine (spine is what the flexibility is called and for a traditional style bow the rule of thumb is to go ten less than the draw weight of the bow) For a 70 pound bow I had to go down to 30-35 spine.
To see better what was happening I bought a camera from a well know auction site for a mere £69. A Canon Powershot SX230HS It's not one of the very fast camera but it will take 240 frames per second at low resolution (320x240) or 120fps at (640x480).
I mounted the camera on an old hard hat to give an approximation to my eye view of an actual shot.
Unfortunately I can't post video on here, but if you want to see if I hit that small white spot, you can see a V short video on my blog. It is compressed so the quality isn't that great.
You will also see that from the archer's perspective, at short range the point of the arrow is lined up well below the target. To allow for this target archers would place a white aiming disc (or "point blanc" in French) on the floor. (The effect is somewhat exaggerated as the camera is above my eye line)
'Point blank' range is the distance at which that aiming spot coincides with the actual target, which for the bow shown is about 40yards. People always incorrectly assume that point black range means zero. It does for a weapon which you aim by looking down the barrel, but there are fewer than you might think, as even with a rifle, your eye and the sights are slightly elevated especially if a scope is fitted.
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Re: Slo' Mo' Hat Cam
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