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I understand, but sometimes you encounter a dogleg. If you use the 10m spec in the situation I mentioned above, you will be way out of balance. I just think it makes more sense to use the percentage I mentioned above as a guide to place the foresight point. I don’t think specs of any kind should be abused, that’s all. Thanks for the reply.
MHI would like to mention that some people feel it’s necessary to balance turns within tenths of a foot. That’s a waste of time. The instrument should be peg tested before each run. It doesn’t take long, and any unbalanced turn errors will be negated. Thanks for the reply.
MHI didn’t know that.
MH- Posted by: @field-dog
I just think it makes more sense to use the percentage I mentioned above as a guide to place the foresight point.
I don’t see that percentages have much to do with the errors that can happen. The error grows with unbalanced distance, whatever percent it is. Misleveling in the instrument causes the error to grow proportionally to the difference (FS – BS). Error from refraction and curvature, if not calculated for each sight, grow proportionally to (FS^2 – BS^2) = (FS – BS)*(FS + BS). There are no percentages in there.
. - Posted by: @field-dog
I understand, but sometimes you encounter a dogleg.
In most situations where you turn a corner, you can pick an instrument setup that minimizes the unbalance. There is no reason the level needs to be on line between the points. And adding one more turn with a short BS and FS may be preferable to having unbalance.
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