Tools
The Gradation Curve pane also reads Input and Output values. These numbers show the “before” and “after” values of the pixels at the point you placed on the curve. The Input value shows the brightness of the pixel before the curve is applied, and the Output value shows the brightness of the pixel after the curve is applied.
The key to both Tonal Range and Gradation Curves is to be conservative with their use. Using these tools to attempt to correct an image that was poorly exposed will not result in a high quality image.
The Film Curve tab shows the default film curve and ISO value of the Phase One H 5.
Tools
Unsharp Mask
The name “unsharp mask” (USM) can be misleading. Using this tool actually gives an apparent increase in image sharpness by enhancing the edge differences between pixels of different colors.
When applied to an image, the software evaluates the contrast differences between pixels and either enhances the difference or not, based on your settings.
There are two controls over the USM:
Amount
The amount of change is entered here as a percentage. The higher the setting, the more sharpening will be applied.
Threshold
The threshold level controls at what level the sharpening will begin. At the default “0” setting the sharpening amount is applied to every pixel.
A third option found in many imaging programs, Radius, is fixed in the software application at about 1 pixel.
Using this tool to attempt to sharpen an image that is clearly out of focus will not give a pleasing result.
However, an image that appears to be soft, with low color contrast, can be significantly enhanced by careful application of USM.
5.6 | 5.7 |