Last week saw how to despill images, and this week’s class started by showing us how to protect areas where you needed to keep the green, for example, if the actor is holding a green bag or the acter eyes are green. To protect this we can use marge operations in this way.
Minus: by minus Original from the despill plate you get the luminosity lost by removing green.
Multiply: the background over those luminosity values.
Plus: it is over original to add a background in the transparencies.
We can also, use the saturate node to desaturate and this help to remove unwanted colours.
Add Mix was a new node we used in this class, Add Mix works like a marge but with Add Mix, we can control the alpha from both channels by utilising the graph.
Additive Key is not a node but it is an image-blending technique used to recover fine detail in difficult areas such as hair, soft transparencies and motion blur, edge treatment and despill can create very good results to better integrate your plate to the background Additive Key manipulates lightness values in the fine details and adds it to the background under the foreground plate. To create this you need to take an average of the plate by using a constant and then minus it with the plate. Use the Saturation to despill then use Grade to adjust the alpha, and then Merge to the background.
Sometimes when working with greenscreen we might get lucky by getting a clean plate, which means a plate only with the background. This helps a lot when you get this because we don’t have to do IBK and just use divide and multiply to remove the greenscreen.
In the next, we saw how it affects only the ages of the hair to get more of the dilates. By using the colour Lookup node we can control the RGBA to only affects the particular area. Then mask we can mask it with a roto. Mask to the grade and adjust the transparency.
we also saw how to make take alpha from an image without using any key, but this way take an average of the greenscreen and then the difference it with the plate.
Edge Smearing Gizmo, help to restore the edge of the image. This gizmo works better than Edge Extend and is softer. Next, we saw how to make our own Gizmo and I felt this was very helpful for making our work easier.