Using LAD for printing control.

Routine procedures for sensitometric and chemical control of processes must be well established. A daily check of printer light output is also important, usually with a printer photometer.
Run Printer tests to establish the printer set-ups necessary to obtain the proper LAD densities on the intermediate and print films used in the laboratory as follows:

Prepare a printer test loop, including a processed control strip, and the Lad Control Film.
Print the printer test loop on to the intermediate, internegative and print films currently being used by the laboratory.
The LAD Patch should always be printed at the "Normal" printer settings (such as 25-25-25) for the laboratory. Exposure adjustments for the different emulsion batches should be made using the trims or filter pack.
Read the LAD densities of the processed film. Make an exposure correction using adjustments to trims but retaining normal control settings, and reprint until the densities match the aim densities as listed in Addendum 1. The density change you should expect for each printer point change is outlined in Addendum 2. Apply any densitometric crossover readings that may exist between Kodak and the laboratory. Also, correct for any known process drift.
The suggested practical tolerances for LAD densities for intermediate prints are as follows:
Answer prints - + 0.08
Intermediates - + 0.12
Release prints - + 0.12*
* Differences between the three colours should not exceed 0.10 on prints. For example, Print No. 1 as described below would be considered acceptable, while Print No. 2 should be rejected.

Set the analyser control for the proper format, film tape, colour temperature, etc.
Place the LAD Control Film in the analyser's gate so that the frameline will generate a "reference white" on the display.
A 0.70 silver neutral density filter is placed in the lower left corner of the display tube over the "white reference" to produce a "reference grey".
Set the control dials for the "normal" printer set-up, (25-25-25).
The calibration controls are adjusted to obtain a visual match of the LAD patch to the "reference grey". An experienced colour grader can easily obtain this match to within + 1 print point.
Some adjustments in the density or colour of the reference filter over the display tube may be required. The 0.70 silver neutral density is merely a starting point. Increase or decrease the neutral density value or add Colour Compensating filters if needed until grading decisions made on the analyser agree with the prints. For example, if prints are consistently 10 CC red (when the LAD patch is on aim), the reference filter should be made slightly redder with a 10 CC red filter.
Other neutral density filters may be chosen to match the six-step grey scale along the bottom of the frame to provide verification of the contrast of the electronic colour analyser.

Silver neutral density filters can be specially ordered from Kodak. They are called "KODAK Flashed Density on Film", available in two sizes: 4 x 5 inch (Cat. 164 7718) and 8 x 10 inch (Cat. 173 4607). The specific density must be specified.
KODAK 'WRATTEN' Neutral Density Filter 96 can be substituted for the silver density filter. The WRATTEN 96 tend to be slightly yellow. Therefore, to make a grey filter, a 10 CC blue must be added to the WRATTEN 96.