KB85664187: Focus Search on CDI

Description

The focus search is used to determine the exact position at which the laser spot on the plate is the most focused. For this, several lines which are set in the field “tracks”, are engraved using different focus unit positions.

Procedure

1. Mount a plate on the drum and move the laser head to the correct starting position.
2. Launch Expose.
3. Go to Options > Focus Search.
4. Select the Plate Material Type and Thickness.
5. Click the Advanced button to preview/ change the settings given below:
   
   1. 0.2 mm Axial advance                                                                                             
   2. 0.2 mm Focus advance
   3. 30mm = Start (around drum)
   4. 40mm = Height (around drum)
   5. Tracks = 20
6. If the plate is a partial, check the Partial Plate box, otherwise, click the OK button.
7. In Expose, click the Start (green) button to image.
8. After the CDI has engraved these tracks, you will be prompted to determine which of these tracks are the most focused. Identify the Best Track either by looking through a microscope with a flash light or by looking at the engraving directly and judging whether the darkest (thinnest) part of the engraving in the center or is right or left