Universal Laser Systems ULS-25PS, Operation Manual

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underneath, the laser system will then engrave out the fill and cut the hidden outline on
top of the fill. This is a common occurrence when using pre-drawn ClipArt designed for
laser printers. To prevent this from happening, turn on the B/W Raster feature in the
driver. This feature disables the cutting mode and converts all visible outlines to
engraved objects and ignores all hidden outlines.
Optimizing Speed
It is advantageous to engrave an object in its longest direction because total engraving
time will be reduced when the motion system has to make fewer stops and starts. If the
engraving object is longer than it is tall, a greater engraving speed can be achieved by
rotating the graphic 90 degrees and placing the material in the laser system sideways.
Be aware that some graphics programs do not allow the rotation of bitmaps. In this
case, it may be necessary to use bitmap image processing software to first rotate the
bitmap before importing the bitmap into the graphics program. If the artwork contains
engraved objects of the same color with a great deal of space between them in the
engraving direction, processing time can be longer since the laser must make long
strokes to engrave both objects at the same time. To reduce engraving time in cases
like these, use different colors for each of the objects but assign the same power
setting to both colors. This will cause the laser to engrave one object at a time,
skipping over all blank space, which in many cases will reduce engraving time.
Bitmaps
There are three types of bitmaps available. They are monochrome, grayscale, and
color. Bitmaps are patterns of dots blended to form pictures. Most bitmaps are created
by scanning artwork into a computer through a scanner. Others are created by drawing
them in a bitmap image processing program. Only monochrome or grayscale bitmaps
are used by the laser system. The driver handles color bitmaps the same as grayscale
bitmaps. Since color bitmaps use more memory, they are unnecessary and are
therefore
NOT recommended. Monochrome bitmaps are used when scanning and
engraving line art or camera ready black and white images. Grayscale bitmaps are
used for scanning and engraving photographs even if they are color.
When scanning black and white images, scan at least 600 DPI. The higher the DPI,
the smoother the image will be. Scanning in at 300 DPI is the minimum resolution for
scanning line art (monochrome bitmaps), but 600 DPI provides a significant
improvement in the image quality. Grayscale bitmaps (photographs) usually should be
scanned at no more than 300 DPI. Scanning at a higher DPI for photographs does not
effectively improve image quality but consumes more memory. As a rule of thumb,
scan photographs at 300 DPI and line art images at 600 DPI.
There are several different bitmap formats available: TIF, BMP, PCX, and others.
The format makes no difference to the laser system. The difference in formats involves
how they are stored on the computer’s hard disk. Bitmaps cannot be edited in most
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