Viewing Density Trends with Expresso Mini
ExPresso Mini is a SpectroDENS feature that shows print density trends as a bar graph. Press operators can use this capability to track trends across multiple sheets or across the press width. It is a simple tool to help maintain print uniformity.
STEP 1: Use the up/down arrow buttons on SpectroDENS to select the Measurements Function menu on (bottom left menu). Scroll through the menu and select the Expresso Mini function. Expresso Mini displays results for last 10 measurements per color. Subsequent measurements will wrap around and overwrite the earliest measurements.
STEP 2: Measure solid ink densities across the sheet. You can measure all solid colors in same ink zone and then move on to another ink zone OR you can measure the same color in all ink zone and then repeat for other ink colors. Density values are shown underneath each location on a bar graph. Density differences are from the average density of all measurement locations. It is that simple.
STEP 3: Density can also be compared against reference values and defined tolerances (instead of the average density value). Switch on the delta mode by selecting the Delta (triangle) icon. Measure as above in Step 2. The bar graph now shows the reference value and density deviations. Color code indicates pass/fail status of measurement.
Navigate to Configuration (bottom right menu) and select “Density Reference Setup” from the menu.
Enter in your reference solid ink densities into one of the 5 Reference Sets. Enter tolerances for each solid color. Finally, return to main screen and select the Δ icon to switch on DELTA mode.