Level 2 Help for NS001

INP

The name of the input dataset


OUT

The name(s) of the output dataset(s).


CHAN

Channels to be logged. The default is to log all channels, in order. You
may select any subset to be logged; they will be output IN THE ORDER LISTED.


DATE

Date of data acquisition. This is the date that the mission was flown. The
date is usually written on the tape label, or it can be retrieved from the
flight log. The preferred format is ddmmmyy, e.g. 01FEB85.


SITE

This is the user specified site name.


FLIGHT

NASA/AMES flight number. This is usually written on the tape label; otherwise
it can be obtained from the flight log.


LINE

Line number. This is usually written on the external tape label.


RUN

Run number for this flight line. This is usually written on the external
label of the tape.


TEXT

Channel descriptions to be entered into the VICAR label. If you wish to add
annotation to individual channels, you may do so by entering the default string
followed by the desired additional information. You are urged to always include
the default string, unless the text is incorrect for this data.


START

This parameter is passed to the program GRADREM. It designates the first line 
of the gradient estimaion region. GRADREM will not be run on the images if this
parameter is defaulted.


LENGTH

This parameter is passed to the program GRADREM. It designates the number of 
lines in the region selected for gradient estimation. 


LINC

This parameter is passed to the program GRADREM. Every LINC-th line is used in
the region specified by the START and LENGTH parameters to obtain the gradient
function estimate. The default is 1; that is, every line is used.


FILT

This parameter is passed to the program GRADREM. After the gradient estimation
function is computed, a FILT element (lowpass) box filter is used to smooth the
function. This value must be an odd integer. The default value is 101. (The
default when running the GRADREM program itself is that no filtering is 
performed. The NS001 procedure requests FILT=101 unless the user overrides this
value. To get no filtering, specify FILT=1.)


GAIN

This parameter is passed to the program GRADREM. The DN for a pixel output from
GRADREM is computed by the formula

		DNout = GAIN * (DNin/gradient function)

GAIN specifies the factor to be used in the computation. Usually, GAIN should
be about the same as a typical gradient function value (which is the average DN
for pixels in the estimation region of the image). If GAIN is too large, pixels
may be saturated to DN=255. If GAIN is too small, some of the dynamic range of
the data will be lost. The default value of 100.0 is usually appropiate.


HIST

If the value of this parameter is WIDE or NORMAL, it is passed to the program
HIST. If the value is NONE, HIST is not executed. The NORMAL value leads to an
output format limited to 80 characters in width and is convenient for terminal
output. The WIDE value leads to an output format that is up to 132 characters
and is often used for hardcopy output.


SCALE

This parameter is passed to the program C130RECT. It specifies the aspect ratio
(expansion factor) used during panorama correction. The default value of 1.0 is
the correct value if, at nadir (along the column of pixels in the center of the
input image), the inter-pixel distances are the same for vertical and horizonal
lines. The larger the value of SCALE, the wider the output image becomes. The 
panorama correction for NS001 data yields an image 954*SCALE pixels wide.