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Re: Comparison, Pan of Oil vs Mirror Artificial Horizon
From: David Fleming
Date: 2015 Jun 23, 21:11 -0700
From: David Fleming
Date: 2015 Jun 23, 21:11 -0700
What method did you use to determine "overlap" when superimposing the images?
With small side error overlap means the direct and reflected images are slightly displaced horizontally but vertically but top and bottom edges are at same height, if there is no side error then judge by sharpness of the total image.
Did you turn the micrometer drum in same direction for edge-to-edge observations? By that I mean NOT turning cw for one and ccw for the other.
I did not attempt to systematically approach the measurement from any one direction in other method. As I approached a reading the micrometer was adjusted to and fro till overlap looked as above or if edge to edge just touching.
What do you believe your IE to be from superimposing vs. edge-to-edge?
As indicated I adjusted side error out for the edge to edge measurement as that would be a systematic error so I can not say that one measurement was better than the other in terms of accuracy, we never know that in any event. What I can say is that the ovelap gave an IE of on the arc 3.6 +/- .4 moa while the edge to edge gave on the arc of 3.1 +/- .7 moa and I had to make twice as many measurements for the inferior measurement.
Dave
