Adjust Gamma...

Argos uses a nondecreasing function, f(x) ∝ x10 to map x, the number of profiles passing through a pixel to, I, the brightness at the pixel. This operation allows you to adjust this mapping by specifying a γ value. An example of the dialog for this operation is the following left panel; the corresponding x-rayed PCP is the following right panel. Argos uses 0.22 as the default γ value. Loosely speaking, the horizontal axis is the number of profiles passing through a pixel; the vertical axis is pixel intensity.

Note

---> images/hkf-adjust-gamma-dialog-default.png <---
---> images/plot-pcp-x-rayed-example.png <---

Positive gamma values make images brighter and make it easier to see low-density pixels, as illustrated by the next 2 figures.

Note

---> images/hkf-adjust-gamma-dialog-positive.png <---
---> images/hkf-adjust-gamma-x-ray-positive-gamma.png <---

Negative gamma values make images darker and can help you visually filter out low-density pixels, as illustrated by the next 2 figures.

Note

---> images/hkf-adjust-gamma-dialog-negative.png <---
---> images/hkf-adjust-gamma-x-ray-negative-gamma.png <---