QA BULLETINS (click here to return to List)

1. OVERVIEW

Normal printing density of a perfect normal should be around 80 / 80 / 80 (b/g/r). The aim of the Paper Test (TEST C/M) and the Paper Matrix (TDPM C/M) should also be set to this value to optimize the Matrix Operating Point (center of Matrix). The aim of the Paper Test and Matrix can be shifted without affecting printing aims by changing the RET of the (dedicated) Film Channel used for paper tests.

2. PROCEDURE

As already mentioned, a separate Film channel should be used for Paper Test (TEST C/M), Paper Matrix (TDPM C/M) and Basic Slope Procedures (TDP0 C/M). This channel should have the same NOD / MAD data as the most popular Film Channel. The slopes (F1P / F1N) should be set to 1.000, UPD - OFF. The original PAP of the Paper Channel was probably established by "tweaking the aim" of the work, until satisfactory, (using whatever RET in the Film Channel).

After the work is printed satisfactorily (by adjusting the PAP), the Paper Test is probably not at 80 / 80 / 80 anymore, and should be re-adjusted.

First turn the online densitometer off with the command TDM OFF. Then call up the Master Paper Channel and enter the command PRD, which now allows setting the new aims manually to 0.80 / 0.80 / 0.80.

Run a TEST C and read the processed print, using the online Densitometer and the command TDRE (instead of TEST M) to read the Test Print. The RET of the Film Channel (used for Paper Tests) will be adjusted (automatically) to the new aim, without affecting the PAP of the paper. Repeat tests until satisfied.

What is achieved by above procedure, is to adjust the Paper Test to new aim (80 / 80 / 80) without affecting work (as only the RET of the Film Channel used for Paper Tests is adjusted).

After establishing the new aim, the Paper Matrix (TDPM C/M) should be re-run if the original aim was +/- 0.07 or more different from 80 / 80 / 80.

3. ADDITIONAL INFORMATION

• FNS-QA-006 using TROD to EVALUATE PAPER MATRIX
• FNS-QA-007 PAPER MATRIX PROCEDURE

This page last modified: May 08, 1997
copyright FINISys Inc. 1997, author: R. Ganahl