Session #2 with the laser engraver used simple gray scale "weave" patterns and two new wood samples, maple and what could be honey locust. Here are the results and the gray scale designs used to create them. Unlike the earlier redwood samples, neither of these woods have significant differences in grain hardness - so there are no harder growth rings that don't "cut" as easily next to softer wood which does burn easier.
Here's a close up detail shot . As you can see, the laser creates a fabric like texture where ever it burns. A light "last pass" at low laser power and at 600 dpi ,rather than 300 dpi used in the first pass, might soften the created texture. Will add that to the list of experiments to try,
In this second session with the laser I also tried some gray scale 3Dimages I found on the internet to see how well THEY worked for low relieve gray scale "carving". The results are much more subtle, Here are the gray scale images that were usedto create the "carving" in the sample to their right. The results indicate that the laser, in 3D mode, can do very subtle and nuanced "carving" that would be difficult to impossible to do manually.