Scale
Menu
The Scale Menu is used to set
the upper and lower limits and the distribution of colors, based on pixel
values.
Linear
Set the colors distribution to Linear.
Log
Set the colors distribution to Log.
Squared
Set the colors distribution to Squared.
Square Root
Set the colors distribution to Square Root.
Histogram Equalization
Set the colors distribution based on a Histogram
Equalization algorithm.
MinMax
Set the upper and lower limits to the min
and max values, or 100%. The image may be scanned to determined these values,
based on the Min Max Options.
99.5% to 90%
Set the upper and lower limits to based on
the specified percentage. A histogram of the data is created and the limits
are set to display the percentage, about the mean value.
ZScale
Set the upper and lower limits base on the
IRAF ZScale algorithm. ZScale parameters may be configured via the preference
menu.
ZMax
This is mix of MinMax, or 100% and ZScale.
Set the lower limits base on the IRAF ZScale algorithm and the upper limit
to the max data value.
DATASEC
If the keyword DATASEC
is present, and this option is enabled, data not in the bounding box specified
by DATASEC will not be imaged,
printed, or used in calculations of MinMax and ZScale. The excluded regions
are usually bias strips on CCDs and contain no real data.
Scale Parameters
Invoke a non-modal dialog box to specify Scale
Type, Scale Limits, and Scale parameters.
Scale
Select color distribution scale
Limits
Set the upper and lower limits via algorithm
Scope
For FITS Mosaics, scope specifies if the limits
are applied global across each FITS Mosaic segment, or on a per segment
basis.
Parameters
ZSCALE PARAMETERS -- Select the parameters
for the IRAF ZScale algorithm.
Graph
Display the Pixel Histogram Distribution graph
with either a linear or log scale.