Close ups of a grayscale engrave


#1

Here’s some close ups of the landscape of a grayscale engrave:



Pre-release | Celtic Knot 3d engrave
#2

Just realized you can see in this photo that my desk is absolutely not real wood. Hahaha. At least I dont have to worry about growing allergic to it =P


#3

What material is that?


#4

paperboard


#5

reminds me of halftone newsprint. could do some interesting things with tiles and a tool like the rasterbator i suspect:

https://rasterbator.net/

one of my favorite tools to decorate an old apartment i shared with roommates (because it’s so cheap!)


#6

uh, great name - bookmarked!


#7

:stuck_out_tongue_winking_eye: searching for “Drooling” emoji !

The more I see of GF’s capabilities, the more I realize I’m going to need to become a better artist to take advantage of them all. As an artist, I’ve just learned how to make an early hominid hand axe, and I’m about to be handed a full workshop of power tools, and delicate sculpting tools… wow.


#8

Looks very stochastic (that’s good, prevents moire) although seems weird at the lower densities on the left, as there we white veins running through them…


#9

I’m pretty sure what’s going on on the left is moire. This is supposed to be a gradient of black to white, left to right. It gets so dense that it seems to be interfering with itself, and canceling out where it thinks it needs to engrave.

Its something that seems to have been lessened recently, and hopefully more. It’s great for photo engraves, but not so great for 3d engraves, or graphic designs etc. I’m hoping in the future it will be something we can turn off and on.


#10

I agree. Even a bit mezzotint-y.


#11

Nice test, thanks for doing that!


#12

Error diffusion dither, looks like Judd kernel (as close as I can get from a limited sample), not using serpentine scans (so showing snakes), and having problems initializing the first few rows. Also looks like it may not account for dot gain (shape + overlap) and only use a simple LUT calibration.

P.S. Yes, I have written way too much dithering code in my career.


#13

Ha nice! What do you do for a living?

I’m pretty sure at this point they are using Floyd-Steinberg for dithering.

I’m hoping they’ll make dithering optional, so we can use the algorithm of our choice based on what we’re working on. It’s great for photos, but can be a pain when working with smaller details, flat areas, or 3d engraves in general


#14

Simple Floyd-Steinberg weights would have more snakes, and even more problems with the first few rows. Using a serpentine scan would reduce the snakes, but can show other visible artifacts. The over-sharpening at value boundaries is typical of larger error diffusion kernels (and the bigger the kernel, the bigger the artifact).

Yeah, I kind of hope they’ll have a halftone pattern (clustered dot makes it easier to calibrate) in addition to error diffusion. If not, I may just reuse some halftone code I have and export it as a bitmap.

I think I’ll keep the specifics of my background off the public site for now.
But I wrote my first error diffusion based color printer driver back in 1988, and wrote a 3D error diffusion driver for a high end color 3D printer about 3 years ago.


#15

Maybe this is a naive question… Why wouldn’t you dither in your app of choice rather than letting the GF app do it? This way you have complete control over the output?


#16

Yes you would only expect the output device to do it if it was just on / off and you wanted to simulate grey scale. I thought GF was supposed to be able to modulate the beam for true grey scale.


#17

On some materials, certainly. With many materials that method simply won’t be applicable so you’d need to dither. My comment was solely regarding the dithering process.


#18

Perhaps if you send it an image that is already dithered, i.e. black and white, then it will just engrave it as is. If you send it a grey scale and it is doing a black and white type engrave then it has no choice but to dither it itself.


#19

Right. That’s what I was getting at. So I’m suggesting dithering prior to sending it to the 'forge. But I might be way off base with that thinking. No clue. Just makes sense to me.


#20

Nice, you’d know better than I. I’m just going by what it says in the files sent to the front end. That might just be for display. They might be using something more high end for engrave renderings on the server side