Low the harnessed implement to a flat surface until the embedding legs touch it and the depth control wheels are in the air.

降低安装设备放置平面直到接触到掩埋臂，并且深度控制轮悬空。

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Since viewpoint correction only works on flat surfaces, any image which is viewpoint corrected must only have control points placed on a single flat surface.

由于观点修正只能在平坦的表面，任何形象，是纠正必须只能有控制点放在一个平坦的表面。

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