A well-made composite is based of a multitude of experiences.
One must be able to make a distinction between the important and less important, the easy and the more time consuming solutions. A highly detailed, accurately finished reflection for example could avert the attention from other, harder to handle parts of the image.
Observing nature helps a lot in creating realistic surfaces with their inherent flaws and random patterns.
The experience coming form shooting films and stills proves to be very useful in modeling lighting structures, developing masks, and determining the correct defocus and motion blur values.

 

 
 
 
 

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