Dear Colleagues,
I know not where The esteemed Bob got his figures from.
However I took a decidedly unscientific approach to this (as you might expect).
I simply used the evil photoshop to tell me the approximate location of the centre of each pinhead and the location of the start of each trail.
Each of these arcs subtend the same angle.
Using the power of excel and a few moments of my time, I entered these points and wrote a function to determine the angle between a point and the end points of the arc.
I then made the bold assumption that the pins were in a relatively straight line and found the line of best fit through the starting and ending points.
This point, fed into the equation to find the angles yeilded almost identical angles for each arc.
My guess is therefore (to the nearest pixel) 75 pixels from the left and 174 pixels from the top. Thats about a third of the way across the centre of the white circle.
This interestingly, gives an approximate shuter speed of almost exactly 3/20 of a sec
I have no idea how close this is to reality, but it was fun. Eslecially for a technophobe like myself.
Best, Bob
p.s. Digital is *bad* (mkay)
my raw figures:
head
140 159 193 158 225 142 322 130 388 116 448 104 509 97 566 84 621 75 672 62
Tail
139 194 185 218 248 233 312 258 375 280 434 298 492 324 549 340 600 363 650 376
Bob Talbot wrote:
Estimated origin, pixels: 602 1341 RMS error 2.17 pixels from residuals of Least Squares fit.
HeadX HeadY TailX TailY 897 1405 897 1262 1107 1532 1140 1260 1392 1591 1419 1179 1681 1696 1723 1128 1969 1794 2017 1061 2237 1877 2293 1006 2497 1981 2565 977 2746 2075 2829 917 2986 2164 3071 875 3209 2225 3298 816
