First of all I'll explain the basic principle of painting clouds.

首先我会解释基本的法则。

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In spite of this I had been painting clouds in a particular method, which had not been generating satisfying results for many years.

虽然我用一种独特的方法来绘制云彩，但是多年来并没有得到满意的结果。

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Once we get the general area of our clouds, we want to drop the brush opacity to 20% and start slowly painting away our detailed areas.

一旦我们得到了云彩的大概区域，要将画笔不透明度调为20%，然后开始慢慢地擦除区域中不需要的细节。

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