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too thin and thinner parts of characters and thin lines may disappear altogether. The opposite effect
would occur on inverted images such as white text on a black background.
How to Tune Image Enhancement Settings
These three parameters (CONTRAST, DEFINITION and DENSITY) work together to compensate for
laser response when rastering at higher speeds. For a given material at a given speed, they must be
determined by testing. If you use the materials database, these values are already determined for
you. You can look up these settings for a particular material in the database by selecting that
material in the materials database tab and selecting edit. Keep in mind that these settings are tuned
for the particular raster speed and power level stored in the database and if you need to change the
speed or power significantly for your application, you may need to establish new values by testing.
Also, remember that these settings are for high-speed engraving on sensitive materials such as
anodized aluminum and acrylic and may not be necessary for your application.
Step 1: Establish the nominal power setting.
The enhancement settings work best when you are not overpowering the material. The first step is
to establish the minimum laser power necessary at the desired processing speed to mark the
material or to engrave the material to the required depth. You should not use more laser power
than necessary. The best way to determine this is to engrave a 4” (101.6 mm) wide by 0.5” (12.7
mm) tall solid black rectangle in the center of the processing field. Use a scrap piece of material to
adjust laser power in a series of 5% increments at the desired processing speed until you establish
the minimum power level required to produce the desired result. Make sure image enhancements
are DISABLED.
Step 2: Use text to set the CONTRAST parameter.
Type in a string of text, using the Times New Roman font, set at 8 or 10 points in size. Make sure
that the text string is at least 6 inches long and that the string includes punctuation marks, spaces,
lower- and upper-case letters as in the following example:
This is a test to set contrast definition and density for High-Speed Engraving
Engrave the sample text with the settings established in step 1 on a scrap piece of material, but this
time ENABLE Image Enhancement and set CONTRAST to 0, DEFINITION to 0, DENSITY to 100 and the
TUNING value to +4. The results may appear fuzzy, some thinner elements of characters may be
missing, and overall engraving quality may not be as good as expected. Keep adjusting the
CONTRAST upward in increments of 5, engraving another sample between each adjustment (you
may want to engrave each sample right beneath the previous one so you can compare them). Note
the results after each trial. The objective is to adjust the CONTRAST just enough to cause thin parts
of the text in the high-density areas of the text to be sharp and clear. Ignore the appearance of the
ascenders and descenders that stick out above and below the dense areas of text as they will be
adjusted using the DEFINITION setting. Setting CONTRAST too high can cause the characters to
appear “fat” or “bold” so find the minimum value that gives good results.
Step 3: Adjust DEFINITION to enhance the ascenders and descenders.
Now, increase the DEFINITION in increments of 5 at a time until the ascenders and descenders begin
to appear sharp and clear. The objective is to increase the setting just enough to cause these parts
of the graphic to match the appearance of the high-density areas. Setting the DEFINITION too high
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