ISOCAM Interactive Analysis User's Manual Version 5.0 - ISO - ESA

9.3. RELATING DATA PRODUCT TYPES TO FILENAMES 63
9.3.4 Auxiliary data products
Additional information, such as pointing and spacecraft position and velocity, are also provided
on the CD. ISO CD-ROM users can find IRPH and IIPH in the directory /products/-
pmmmmmmm/nnnxxxyy and ORBIT in /products/pmmmmmmm/others.
IIPH Instrument Instantaneous Pointing History. Contains instantaneous pointing information
for CAM during your AOT. Note that this is an essential file for calibrating your data.
Users have experienced difficulty with very old IIPH files, i.e. generated by OLP prior to
version 4.0, see Section E.2 for details.
The IIPH equivalent for CAM parallel mode is CIPH.
IRPH Instrument Reference Pointing History. Contains reference pointing information for
CAM during an AOT. It contains similar, though less comprehensive information as the
IIPH. CIA uses the IRPH when analysing CAM parallel mode data.
The IRPH equivalent for CAM parallel mode is CRPH.
ORBIT Contains information on orbital parameters for all ISO revolutions up to and at the
very least including the revolution during which your AOT is performed.
Strictly speaking this is a CAL-G file, but to follow the organisation of the ISO Data
Product Document it is placed in this section.
9.3.5 Calibration Data Products
Calibration data are available in two formats, CIA’s Calibration Data Structures (CDS) and
CAL-G FITS files.
9.3.5.1 CIA’s Calibration Data Structures
All the necessary calibration data are delivered with CIA in the form of CDSs (see Section 9.4.3
and Section 15.3), with notifications of updates available by email. Access to the CDSs is usually
handled by CIA routines and so is mainly transparent to the user. For CIA users this is the
best way to deal with calibration data. It is certainly the most convenient and has the added
advantage that CDSs will contain the most up-to-date calibration data.
9.3.5.2 CAL-G FITS files
Alternatively, calibration data in the form of CAL-G FITS files can be sourced from an ISO
CD-ROM or the IDA at
http://www.iso.vilspa.esa.es/
Of course the ISO CD-ROM files are current when the CD is pressed while the archives will
always be up-to-date. Note however that CAL-G files from both these sources are official ESA
releases of calibration data. There will usually be some time lag between the release of ESA
official CAL-G files and the ISOCAM consortium official CDSs that are part of CIA. Again,
another reason why CIA users generally only use CIA’s CDSs.
On the ISO CD-ROM the CAL-G files are found in the directory /products/pmmmmmmm-
/others and in subdirectories below this. This should be clear from datalist.txt. Generally, the
names of the CAL-G files begin with CCG*, where* refers to the either the SW or LW detector.