The observing parameters are similar to the ones to be given for the photometric modes. Here, however, a wavelength range is selected rather than a filter. Observers select the range they are most interested in, and the detector dynamic range will be set appropriately.
STARING OR CHOPPING MODE: definition of the observing mode
if CHOPPING MODE is selected (see Sect. 3.1 and
6.2 for details):
CHOPPER MODE: rectangular, triangular or sawtooth chopping
CHOPPER THROW: angular separation (in arcsec) between target and
reference position
CHOPPER AVOIDANCE DIRECTION: direction to be avoided by the
chopper
FULL AVOIDANCE ANGLE: angular region to be avoided by the chopper
POINT OR EXTENDED SOURCE: specification of source type; this
parameter defines whether the MAXIMUM UNSATURATED SOURCE FLUX is given
in Jy or MJy
LINE OR CONTINUUM FLUX: specify whether the
parameters MAXIMUM UNSATURATED SOURCE FLUX and DETECTION LIMIT (to be
specified below) are given as line or continuum flux (see
Equ. 23).
MAXIMUM UNSATURATED SOURCE FLUX 2.5 TO 5
: upper
limit of source flux to be measured in the wavelength band 2.5 to
5 (PHT-SS detector) without saturating the
detector.
DETECTION LIMIT 2.5 TO 5 
m: lower limit of source flux
in wavelength band 2.5 to 
(PHT-SS) that shall
be measured with the specified S/N ratio within the INTEGRATION
TIME
MAXIMUM BACKGROUND FLUX 2.5 TO 5 m: expected maximum
background flux at source position including all components
(see Sect. 6.2)
MAXIMUM UNSATURATED SOURCE FLUX 6 TO 12 m: see above
DETECTION LIMIT 6 TO 12 m: see above
MAXIMUM BACKGROUND FLUX 6 TO 12 m: see above
RANGE SELECT: wavelength range for which the observation
shall be optimized; either 2.5 to 
or 6 to
or both
PEAKING UP REQUEST: for high photometric accuracies or high
sensitivities peaking-up may be required (see below and ISO Observer's
Manual).
INTEGRATION TIME or S/N: the integration
time requested or, alternatively, the required signal-to-noise ratio
The parameter LINE OR CONTINUUM FLUX specifies whether the MAXIMUM
UNSATURATED SOURCE FLUX and the DETECTION LIMIT are given as line
fluxes in units of 
or as continuum fluxes in units of Jy or
MJy/sr (see Equ. 23).
The flux limits to be specified with the parameters MAXIMUM UNSATURATED
SOURCE FLUX and DETECTION LIMIT apply to the whole wavelength range
considered (i. e. 2.5 to or 6 to ,
respectively) independent of the actual source spectrum. They have
to be specified for setting up the dynamic range of the PHT-S detectors.
If the observer selects both wavelength ranges for the setup of PHT-S, it
may be difficult to optimize the detector settings for sources having a very
steep spectrum in this wavelength range.
If the spectral flux differs
from the average flux by more than a factor of 100, it is recommended to
make two separate observations, one optimized for PHT-SL and the other
one for PHT-SS. Note that PHT-SS and PHT-SL are operated simultaneously.