Product

• Lotem^® 400
• Lotem 400 Xpose
• Lotem 200K

Background

The objective performing a delay test is to calibrate the delay parameter for the Data Distribution Board (DDB), so that the exposed horizontal lines are perfectly straight. The plate is exposed at a resolution of 100 dpi, in different delay values. The optimal delay value is the delay value of the best exposure. Lotem Controller automatically calculates the optimal delay values for other resolutions.

Note: Test results do not depend on the plate type, size, or thickness, so this test can be performed on any plate type that the customer uses.

Requirements

• Focus value obtained in the Focus Calibration Test
• Elevation angle obtained in the Elevation Adjustment procedure
• Intensity value obtained in the Intensity Calibration Test
• Resolution value obtained in the Resolution Calibration Test

Procedure

1. Load a plate.
2. Open the Lotem Calibration dialog box:
• For Lotem 400 Xpose—on the Xpose Utilities panel, double-click LotemCalib.
• For Lotem 400—proceed as follows:
1. In Brisque, from the Launch Pad, open the setup panel, and then double-click Devices.
2. In the Output Device Handling dialog box, in the Device section, select Plate Setter > Lotem > Lotem400.
3. In the Operations section, select Lotem Calibration.
3. In the Lotem Calibration dialog box (example shown for Lotem Xpose), in the Calibration Type list, select Delay.
   
4. Select the plate type:
• For Lotem Xpose—in the Current Plate type dropdown list
• For Lotem 400—in Media
5. Define the Plate Policy:
• Load plate—Automatically loads a new plate before the test begins. If you clear this option, you can reuse a plate for additional calibration tests.
• Unload plate—Automatically unloads the plate after the test. If you clear this option, you can reuse the plate for additional calibration tests.
6. Define the Image Offset values:
   • Horizontal offset—the value around the drum in mm
   • Vertical offset—the value along the drum in mm
   If you use the same plate for several tests, use different offset values for each test.
   Note: The (0,0) offset coordinate is located at the upper-left corner of the plate.
   
7. In the Test Resolution list, select 100.
8. In the Test Delay Value (µm) area, type the values for the delay range. For example, if the listed delay value is 124.09 µm, it is recommended that you enter a range of 123 to 125.
9. In the Number of steps list, type the required number of exposures for the delay range. The recommended number of steps is 11.
10. Click Test to initiate the delay test according to the settings. The application performs several exposures.
11. Develop the plate and examine the results.
12. Determine the optimal delay value for a resolution of 100 dpm. The optimal delay value is the delay value of the best exposure. Type this value in the Delay Value box.
13. Click Save. The optimal delay value is transfered to the Lotem controller. Lotem Controller automatically calculates the optimal delay values for other resolutions.

Note: If required, click Get to load a previous delay test result from the Lotem Controller application.

Technical contact(s)

Content owner: Mario Amir
See the Escalation page for escalation contacts.

Date submitted

07 Dec 2003