It is really helpful to be familiar with and practice both approaches.' I always go for the High Pass setup when I need to do a quick retouch, especially when evening out skin. 'The Apply Image and High Pass approaches of separating frequency spatial data of an image are the two main ways of how I use the FS technique,' says Aleksey, 'Apply Image setup is more accurate, but the High Pass setup is quick and helps me to not only customize the separation of skin texture from underlying colors, but also tone down 'hot' highlights on the skin. High Pass Filter: more precise control, tones down highlights, high pass filter radius and blur radius must be the same.