If you want to aim to the center of the target than obtain the center x of the target and rotate to it using the formulas postEd.
In the photo posted, the left edge of the target is roughly at x=0 (assuming a graph is overlayed) and the right boundary is at x=x for the "far" target and x=2x for the "near" target, meaning the centers would be at x=1/2x and x=x respectively. The "near" target will request twice as much turning.
Also please stop using the word
turntable
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