£D printed parts with glossy toner transfer images on

Add Full-Color Images To Your 3D Prints With Toner Transfer

Toner transfer is a commonly-used technique for applying text and images to flat surfaces such as PCBs, but anybody who has considered using the same method on 3D prints will have realized that the heat from the iron would be a problem. [Coverton] has a solution that literally turns the concept on its head, by 3D printing directly onto the transparency sheet.

instrument panel design with toner transfer markings
The fine detail is great for intuitive front-panel designs

The method is remarkably straightforward, and could represent a game-changer for hobbyists trying to achieve professional-looking full-color images on their prints.

First, the mirrored image is printed onto a piece of transparency film with a laser printer. Then, once the 3D printer has laid down the first layer of the object, you align the transparency over it and tape it down so it doesn’t move around. The plastic that’s been deposited already is then removed, and a little water is placed on the center of the bed. Using a paper towel, the transparency gets smoothed out until the bubbles are pushed off to the edges.

Another few pieces of tape hold the transparency down on all corners, and the hotend height is adjusted to take into account the transparency thickness. From there, the print can continue on as normal. When finished, the image should be fused with the plastic. If it’s hard to visualize, check out the video after the break for a step-by-step guide.

There are, of course, some caveats. Aligning the transfer and the print looks a little fiddly at the moment, the transparency material used (obviously) has to be rated for use in laser printers, and it only works on flat surfaces. But on the other hand, there will be some readers who already have everything they need to try this out at home right now — and we’d love to see the results!

We’ve covered some other ways to get color and images onto 3D prints in the past, such as this hydrographic technique or by using an inkjet printhead, but [Coverton]’s idea looks much simpler than either of those.  If you’re interested in toner transfer for less heat-sensitive materials, then check out this guide from a few years back, or see what other Hackaday readers have been doing on wood or brass.

Continue reading “Add Full-Color Images To Your 3D Prints With Toner Transfer”

How To Hide A Photo In A Photo

If you’ve ever read up on the basics of cryptography, you’ll be aware of steganography, the practice of hiding something inside something else. It’s a process that works with digital photographs and is the subject of an article by [Aryan Ebrahimpour]. It describes the process at a high level that’s easy to understand for non-maths-wizards. We’re sure Hackaday readers have plenty of their own ideas after reading it.

The process relies on the eye’s inability to see small changes at the LSB level to each pixel. In short, small changes in colour or brightness across an image are imperceptible to the naked eye but readable from the raw file with no problems. Thus the bits of a smaller bitmap can be placed in the LSB of each byte in a larger one, and the viewer is none the wiser.

We’re guessing that the increased noise in the image data would be detectable through mathematical analysis, but this should be enough to provide some fun. If you’d like a closer look, there’s even some code to play with. Meanwhile as we’re on the topic, this isn’t the first time Hackaday have touched on steganography.

What Exactly Is A Gaussian Blur?

Blurring is a commonly used visual effect when digitally editing photos and videos. One of the most common blurs used in these fields is the Gaussian blur. You may have used this tool thousands of times without ever giving it greater thought. After all, it does a nice job and does indeed make things blurrier.

Of course, we often like to dig deeper here at Hackaday, so here’s our crash course on what’s going on when you run a Gaussian blur operation. Continue reading “What Exactly Is A Gaussian Blur?”

Argos Book Of Horrors

If you live outside the UK you may not be familiar with Argos, but it’s basically what Americans would have if Sears hadn’t become a complete disaster after the Internet became popular. While they operate many brick-and-mortar stores and are a formidable online retailer, they still have a large physical catalog that is surprisingly popular. It’s so large, in fact, that interesting (and creepy) things can be done with it using machine learning.

This project from [Chris Johnson] is called the Book of Horrors and was made by feeding all 16,000 pages of the Argos catalog into a machine learning algorithm. The computer takes all of the pages and generates a model which ties the pages together into a series of animations that blends the whole catalog into one flowing, ever-changing catalog. It borders on creepy, both in visuals and in the fact that we can’t know exactly what computers are “thinking” when they generate these kinds of images.

The more steps the model was trained on the creepier the images became, too. To see more of the project you can follow it on Twitter where new images are released from time to time. It also reminds us a little of some other machine learning projects that have been used recently to create short films with equally mesmerizing imagery. Continue reading “Argos Book Of Horrors”

Nerdalert: German TV Producers’ Amazing Vectorscope Animations

German weekend late-night comedy show “Neo Magazin Royale” has a bunch of super-nerds behind the screens in the production studio. This is apparently what they do when they’re (not) working: making test screens that render as multiple animations on their test equipment.

While others out there are limited to displaying cool graphics on oscilloscopes, these guys have vectorscopes and waveformer monitors. A vectorscope is like an oscilloscope in X-Y mode, but with one screen that decodes the color space and one screen for the audio (in stereo). A waveform monitor that plots out the brightness levels of a test image. Normal studio techs use these to calibrate their colors, brightness, and audio levels.

Apparently, these guys programmed a custom test screen that would: a) encode a small animation of a 20-sided die spinning around the show’s logo in the color channel b) encode the show’s logo in the left and right sound channels, and c) their production company’s logo in the screen’s brightness.

At the end of the video, the director Patrick (in the glasses) admits that they’ve spent about three months working on this project and everyone starts laughing. “And who gets anything from this? Nobody!” says the show’s host.

One way to rectify that, though. Post the source code!