Using a laser engraver, there are many things that must be set just right. One of them is your laser beam. If the laser beam is out of alignment, your engraving may have light and dark areas. The way to check is to laser a line of text in each corner and one in the center of the table. Make sure you are in focus and have the power and speed as you normally wood. Inspect all five engravings. If some of them are lighter then others, the laser beam must be clipping on something. This is telling you that you need a beam alignment. If all five engravings look the same, but it is not as dark as it once was, then it is possible tat the laser tube is loosing power. In ether event, look at the documents below to identify the problem.
Link to article on low power, and the beam alignment documents and the article on the power meter
