From Aperture's Help:
Does that mean Aperture uses separate (per-channel) luminance values to derive the average luminance as opposed to Combined Auto-adjustment which the same Help page explains as the one that's based on the sum of the luminance of each channel which is then added to the colours? What is adjusted exactly?
Next. Considering the meaning of nodes positioned against the histogram mountain in the Curves adjustment tool :
The horizontal line of the graph corresponding to the Ox axis represents the tonal range from the darkest to the brightest spot of the image. In such applications as Aperture, it's In field (for input). If by dragging nodes vertically we re-map dark and light tones then:
When you want to automatically adjust the tonal curve of an image based on individual evaluations of the red, green, and blue channels, you use the Auto Curves Separate button. Red, green, and blue channels are adjusted based on an evaluation of each channel. The Auto Curves Separate button corrects the colour cast in the image in addition to the contrast.
Does that mean Aperture uses separate (per-channel) luminance values to derive the average luminance as opposed to Combined Auto-adjustment which the same Help page explains as the one that's based on the sum of the luminance of each channel which is then added to the colours? What is adjusted exactly?
Next. Considering the meaning of nodes positioned against the histogram mountain in the Curves adjustment tool :
The horizontal line of the graph corresponding to the Ox axis represents the tonal range from the darkest to the brightest spot of the image. In such applications as Aperture, it's In field (for input). If by dragging nodes vertically we re-map dark and light tones then:
- Does that mean that the vertical axis (Oy) (values in the Out field) represents the amount of the tonal value corresponding to the node's position on the Ox axis?
- What is changed when we drag a node horizontally, along the Ox axis?
Last edited: