The Film tab in Matcher is much like the Analysis tab for a Film document. Please refer to that sections for the analysis parameter details. Additional information or differences will be covered here.
When a Film curve is selected, the Subject Zones will be shown at the bottom of the graph. These zones represent the luminance range of the subject necessary to produce a negative that is matched to the current ES value. The Subject Zones are equally divided and labeled as Zones 2 through 8. In addition a gradient is shown to give some visual reference to the range of luminance. This gradient is not meant to accurately convey the subject luminance, it is simply to be taken as a visual reminder of how subject luminance is translated into exposure values.
Along the right side of the graph the Negative Density Zones are displayed. The division of the Density Zones, 2 through 8, depends entirely on the contour of the selected film curve. You'll will see (via the gray dashed lines) the Subject Zones extended up to the Film curve and then extended over to the Negative Density Zones. Here you can see how subject luminance is translated into negative density. Again the gradient shown is not meant to accurately convey the density of the negative but instead serves as a visual reminder of how subject luminance is translated into negative density.
While working with Matcher documents it is possible to approximate intermediate film curves for use in creating new matches. You can approximate a curve based on either a SBR or Average G value as long as the family's curves range contains the requested SBR or Average G value. Approximated curves show in the list of curves along with the other film curves. Depending on how they were created they will be show in one of two ways, either as "SBR ~X.xx" or as "Ave. G ~X.xx" where "X.xx" is the value that was used to create them. Any approximated curves are saved in the Matcher document.
To manage approximated curves, select the "Approximate Curves..." option from the Match menu. This will open the "Manage Approximated Curves" dialog.
Note: In order to manage approximated curves, the Film tab must be active.
The Manage Curves dialog will allow you to add or remove approximated curves. You can create new approximated curves by specifying either a SBR value or an Average G value. Any value can be specified but it must be within the range that the family contains. Adding a new curve will close the dialog and cause the newly added curve to be selected.
You can also remove an approximated curves that have been created by select the curve from the list and pressing the "Remove" button.
Approximated curves are different from normal family film curves in two ways. First they are just approximations and they may no exactly match the values entered to create them but they should be very close especially if they are in the middle of the range.
Secondly, approximated curves are dynamic. Any change to the Film's ES, Flare, Exposure Adjustment, or Analysis Method values will cause all approximated curves to be re-calculated so that their requested SBR or Average G value stays consistent. This is course will cause the approximated curve's contour to change as the curve is recalculated. If an analysis parameter changes such that the requested SBR or Average G value is no longer within the range of the curve family then the approximated curve will not be recalculated and it will be flagged as "(approx. is out of range)."