Rasterbated Images

projectinspo

#11

halftone should work well for engraved images. I hadn’t thought about the issues with using it for through-cuts, but you are quite correct. Nice.


#12

As an alternative, it seems like it would work to etch/engrave the white areas into clear acrylic, paint the back side black, and edge light it. I may just have to try that when our Glowforge arrives!


#13

That’s a great idea!


#14

Another variation on this idea is to use an acrylic with a thin black layer on the top, and either white or glow-in-the-dark acrylic underneath, like this: https://www.inventables.com/technologies/black-on-glow-in-the-dark-laserable-acrylic-sheet Then just engrave away the black layer. (update: just noticed the price: $52 for 12" x 24". Yikes!)


#15

I personally love the precise, mathematical feel of dithering–it would be fun to play with various algorithms using your engrave technique.

There’s a lot of different materials one could experiment with here. In the office we’ve tried stacking thin pieces of wood as a sort of “composite” material. Engraved correctly, you might be able to remove the top layer to show the bottom one. Definitely something to give a whirl one of these days!


#16

Of course, this edge-lit acrylic idea has been discussed elsewhere on this forum in the past, but generally with normal raster images in relation to the 256 grey scale thing. However, some of those discussions also included multiple layers of acrylic or glass, generating a 3D look (like this thread). Combining that kind of layering with this dithering technique, one could literally add a whole new dimension to a family portrait or even a landscape or wildlife photo with natural boundaries between identifiable layers (think receding hills in the background, a striking tree or an animal in the foreground, etc). This is quickly morphing into a really exciting way to augment my photography hobby now too!!


#17

I have a half unfinished project where I take a photograph and highlight the object of interest by putting a piece of laser cut wood over that masks out everything else. I’ll post it when I finish.


#18

The internal reflections caused by the multiple layers will attenuate visibility through the assembly. In some cases, that might be a good thing (sort of a fog effect). But I’m wondering, would it be possible to coat the layers with a glue having a similar index of refraction to make the whole assembly crystal clear? Then the engraved parts would really look like they are floating inside. The tricky part might be keeping the glue out of the engraved areas. Maybe we could apply the glue with a brayer?


#19

What about etching on the back of clear acrylic then mounting the etched side against a black (or clear) background and edge light from the bottom. That would make it look like the etching was inside the acrylic.


#20

I am guessing that internal reflections would only become really problematic with a fairly large number of layers unless it is placed in an especially bright environment, but yes, it would be prudent to do something to mitigate the effects of ambient light bouncing around in there to maximize the contrast.

I was also thinking about gluing the layers together using a solvent based Acrylic ‘glue’ along the lines of @jacobturner’s Acrylic scraps and Acetone recipe. That would be difficult at best to do correctly though; not only would you have to be really careful with the etched areas, it would also be all too easy to trap air bubbles between the layers when putting them together, especially with larger/thicker sheets.

What I plan to try is placing the whole assembly into a frame that closes in all four edges, rather than just having the individual layers perched on top of a lighted base with the other three edges open to the air. That alone should go a long way towards keeping stray reflections between the layers at bay. I also like the idea of etching on the back sides, as that would also keep the front surface completely smooth. Question to the masses: can you apply anti-reflective coatings to acrylic or just get clear acrylic that already has anti-reflective surfaces?


#21

I don’t know how clear-matte spray finish would adhere to acrylic, but that might be an option. There are a variety of translucent vinyl films that could be applied after cutting, for a tinted or frosted-glass look, but I don’t think that would allow the clarity you would want for the whole “floating image” look.
I know that when framing art, the step up to anti-glare glass is a considerable price hike, I have not personally come across anti-glare clear acrylic, but it could exist…?


#22

You can adjust the raster size so that the circles do not overlap. (0-70%) works well.


#23

The easiest way to create depth and contrast in an acrilyc project it to leave the front face alone. You could use an anti glare film or spray that you would apply to a TV or computer screen to stop a mirror like effect unless that’s what you want. There have been a ton of hologram like work pieces made using an infinite light box design. An outer transparent but reflective surface is used then some lights behind it and then a mirror as the back drop. What you get is seemingly infinite depth out of something no thicker than 2 inches. But back to the original message. If you etched the back side of the acrilyc with your design then painted the back after with an automotive grade paint. Something with reflective properties . Lit it up after that with an oled strip ftom the bottom side. You would get an amazing effect where it would look like the logo were floating in thin air.


#24

Something like Stipplegen or Makelangelo can produce more organic results than a halftone screen will give you, albeit at the cost of time.


#25

But you still have the problem of overlapping circles, at least in the example of the original post.


#26

Overlapping circles aren’t inherently bad. They blob together to form larger shapes, which may well suit your design aesthetic. It’s floating circles in a sea of holes that we need to watch out for, because that kind of detail is physically impossible to maintain without some kind of supporting material.

Regardless, most of the workarounds listed above apply here just as effectively. Tweak the settings, and your initial design, until the results are acceptable.

I didn’t mean to imply that that this software would offer fewer challenges than a halftone approach. But it may give you a more visually pleasing and easier to read result.


#27

Agreed. Thanks for the link. It will depend on what you are looking for and the source artwork as well.

Here is a comparison, each has it’s own merits. Litchenstein vs. Seurat


Converting to halftone with stipplegen
Light Box Gobo Holder Frame
#28

StippleGen looks allot more 3D and defined then Rasterbator. Maybe it is just the settings but I do like the effect.


#29

I don’t entirely understand what’s changing between each iteration, but letting it run for eight or nine generations seems to hit the sweet spot in my tests.

Here’s a video demo of the other program I mentioned. It won’t load images on my system, but it looks otherwise promising.


#31

Coming back to update post. I finally got to print out one.

It will go into a light box gobo thingy that I am working on. It has a wemos in it so I can change it and update wirelessly.


Trying to Find Dot Pattern Software