If it doesn't look good in Sketchup, photoreal rendering will not fix it. Photoreal is not real, it is "realistic like a photo". I use it primarily to add shine, reflection, and texture to the image of a scene. In my case, ninety nine out of a hundred renders are the result of post processing that come with real time adjustment of dynamic range, gamma, and contrast. It cuts down the time required to get a desirable photoreal render by 50 to 90 percent.
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