User`s guide

16 | SPECTRAVIEW II - USER’S GUIDE
Custom Gamma Curve dialog
The Custom Gamma Curve dialog is accessed by clicking the Edit.. button in the Gamma Curve section of
the Edit Calibration Target dialog.
Advanced response curves can be selected from presets or custom curves can be created by importing a table
of values.
The following preset curves are available:
sRGB - A curve based on the sRGB specication that includes the offset, transition and slope
components.
L* - A curve based on L* in the Lab specication. The L* curve is intended to be more perceptually
uniform than a simple gamma value curve.
NTSC Video - A curve based on the SMPTE-170M specication for NTSC that includes the offset,
transition and slope components.
SMPTE-240M - A curve based on the SMPTE-240M specication for 1125 line HD video that includes
the offset, transition and slope components.
Custom curves can be created and imported into SpectraView by creating a text le with a list of numerical
values. The text le must conform to the following specications:
Must contain between 3 and 256 values.
Each value must be on a separate line.
The rst value must be 0.
Values must be monotonically increasing.
When imported, the values will be automatically scaled and interpolated to create a Target curve.
•
•
•
•
•
•
•
•