I am still learning about what my Glowforge can do. I’ve done some engraving and had some weird results. I want to use the variable power method, but when doing test strips on wood, the color didn’t seem to fade linearly as expected. That may have been partially due to the masking, but there even seemed to be an S-curve in the color instead of a linear fade. I decided to put that on the back burner, but then this weekend I was testing engraves in acrylic and realized that there really is something off here. Here is the image that I gave the Glowforge;
it’s a straight fade from black to white. The result was not a smooth fade in depth. Investigating further, I found that the most obvious errors occur between 55% and 70% power. Here are the results of engraving the previous image repeated 5 times in the same place (taking breaks in-between to cool the plastic). With each engrave, the errors became more apparent.
Those images confuse me a bit because I can’t tell exactly what I’m looking at… is that being shown with the engrave on the top side or bottom side?
It looks like the errors you are talking about are the dark areas on your second image (on the right hand side)… but it looks like the engrave went from light to dark (light on the left, dark on the right)?
“straight fade”… someone posted a while back about the way that graphics programs create gradients being non-linear in themselves. So I am not sure if the variance you’re seeing is a result of the hardware or the image. Sorry, I cant find that post right now, but you might want to verify that your gradient is linear if you haven’t already?
Furher reading, but not the post I was thinking about. Dang, where’d that go?
Hmmm. My eye dropper tool seems to verify that my gradient is linear. also I have reproduced this several times, and after measuring with calipers, the “hills” are always in the same place, so I don’t think it is a defect in the material. Did Dan have a solution or an alternate curve we should be using?