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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1. Set the global Sampling Level or Time Limit as usual for the full frame step (a)
2. Enable the Extra Sampling feature and set the new Sampling Level for the selected area (b) and the mask (c). Of course, the extra Sampling Level must be higher than the global SL set for the full frame
3. In case of using the Alpha channel or a Custom Alpha channel of the same render as the sampling mask, that channel has to be obviously enabled (d). 

Center

Image RemovedImage Added 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)

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