Tuning the Degamma Feature

This section describes how to tune the Degamma feature to control the de-gamma lookup table of LTM within a DC9400.

Before you begin

Make sure:

The details view shows the settings of the Degamma feature for LTM.
To tune this feature, you need to choose DC9400 > LTM > Degamma in the Features view. For more details, see Tuning a DC9400 Feature.

Figure 1. Details View When Degamma under LTM is Selected
A VTunerServer is accessible.
For information about how to set up a connection to a VTunerServer, see Setting Up a Connection to a VTunerServer.

The de-gamma module converts U10 to U12 by using a 65-point fixed interval LUT, which has the following constraints:

Select the Degamma Enable check box to enable the de-gamma module.
In the Degamma Value spin box, enter the de-gamma value.
In the Segment Points table, use one of the following methods to specify the segment points for the segments along the X-axis.
- Double-click and edit a cell in the table to update a single segment point.
- Click Edit and update the segment points in the prompted Edit Table dialog.
  The segment points must be specified in the same order as the table columns and separated by a comma (,).
- Click Export to export the segment points to a .csv file, edit the file, and then import the updated segment points from the .csv file.
  The order of the segment points in the exported .csv file is the same as that in the table.
The table excludes the first point and the last point, which are fixed to 0 and the maximum value, respectively.

The difference between two consecutive segment points must be a power of two.
In the Segment Steps table, specify the sampling point step in each segment.
The methods of updating the Segment Steps table are similar to those of updating the Segment Points table described in Step 3.

Each sampling point step must be a power of two.