The effective exposure times for the 1983-1985 Epoch ITFs were derived by Imhoff (1984b and 1986), by De La Peña and Coulter (1996) for the 1992 Epoch LWP ITF, and by De La Peña for the LWR ITFs. During the creation of the 1983-1985 ITFs in their own geometric space for the NEWSIPS system, if additional images were deemed usable in contrast to those originally chosen by Imhoff, the effective exposure times were modified to reflect the use of additional images.
Table 6.1 lists the effective exposure times (FN exposure values) for each level of the ITFs used in the Final Archive. These exposure values have been normalized to an arbitrary scale such that the FN associated with the lowest level of an ITF is 0.0.
|ITF||SWP||LWP||LWR ITFA||LWR ITFB|
|Level||Epoch 1985||Epoch 1992||Epoch 1983||Epoch 1983|