Page Comparison

Image courtesy of Quentin Chaillet (www.qchaillet.com)

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• Bitmap, feed with an existing black and white mask in any image format, manually painted or, more frequently, generated from an external channel export.
• Alpha, use the scene Alpha channel obtained during the full frame process.
• Custom Alpha, use any Custom Alpha channel –from object, material or even groups of objects and materials– defined on the scene and obtained during the full frame process.

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Center
Setting an extra sampling on render to refine only the skin areas. The armour and body looks clean at SL 10 (above) while the skin areas still need more rendering, mainly in the back-lit ears. Instead of continuing to refine the whole frame, you can use a mask of the skin areas (center) and get those areas rendered up to SL 18 (below). Image courtesy of Quentin Chaillet (www.qchaillet.com)

During the render 

During the first step of the render process, the engine is rendering the full frame as usual. The SL parameter indicates the global sampling level of the whole image as with any regular render. The Extra Sampling parameter aside displays n/a (not activated), indicating that the extra sampling has not started. (and indicates that the render is still operating in full frame mode).  

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