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Sampling Tools

Primatte’s spill, matte, and detail sampling tools allow you to make fine adjustments to balance between these aspects of your composite. You can find these tools in the operation dropdown menu in the Primatte properties panel.

The Spill Sampling Tools

Using the Spill(+) and Spill(-) modes, you can gradually remove or recover the spill intensity on the foreground object by sampling the referenced color region repeatedly. The difference to the Spill Sponge tool is that Spill Sponge removes the spill component in a single action at one level and does not allow sampling the same pixel a second time. Even though just a small amount of spill needs to be removed, the Spill Sponge removes a preset amount without allowing any finer adjustment. To use the Spill(+) and
Spill(-) tools:

1.   Select the Spill(-) sampling tool from the operation dropdown menu.
2.   In the Viewer, zoom into an area that has some blue edges.
3.   Click on a pixel with some spill on it.
4.   Repeated clicking incrementally removes the spill. Continue this operation until you reach a desired result.
5.   To add spill, select the Spill(+) tool and repeat steps from 2 to 4.

The Matte Sampling Tools

The Matte(+) and Matte(-) modes are used to thicken or attenuate the matte information. If you want a thinner shadow on a foreground object, you can use the Matte(-) mode as many times as you like to make it more transparent. On the other hand, you can use the Matte(+) mode to make the matte thicker in that color region.

The Detail Sampling Tools

The Detail(+) and Detail(-) modes are a refined version of Clean BG Noise and Restore Detail. For example, when you see some dilute noise in the backing area but don't want to remove it completely because it affects some fine detail in a different area, try using Detail(-). It attenuates the noise gradually as multiple samples are made on the pixel. You should stop the sampling when important fine details start to disappear.