I have used a Chrony before, and found one day that it had gotten hung up on something on the tripod and was not fully opened, only by a very small amout.............

Given the velocities it would not take much shortening of the distance between sky screens to effect velocity readings...............

"...A man's rights rest in three boxes: the ballot box, the jury box and the cartridge box..." Frederick Douglass, 1867

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