Control Points are a way to selectively apply filter effects in Color Efex Pro 4. Control points are particularly useful because they are essentially content-aware masks. This article describes how to use them.
Aperture’s control sliders have remained mostly unchanged since the release of Aperture 3 (although the upcoming Photos app is likely to offer a significant modernization). One way to make more sophisticated adjustments to an image’s color and contrast is through the use of plugins. In this article, I will provide an introduction to Color Efex Pro 4, one of my favorites.