Earlier this year, I became aware of a feature in GitHub-flavored Markdown that displays a colored square inline when HTML color codes are surrounded by backticks, e.g., #1f77b4. Although I only recently became aware of this feature, it dates back...

Earlier this month, the Turbo rainbow colormap was released and publicized on the Google AI Blog. This colormap attempts to mitigate the banding issues in the existing Jet rainbow colormap, while retaining the advantages of its high contrast; note that...

Pannellum 2.5 has now been released. As with Pannellum 2.4, this was a rather incremental release. The most noteworthy change is that equirectangular panoramas will now be automatically split into two textures if too big for a given device, which...

Last month, I presented a preliminary analysis of ranking color sets using responses collected in the Color Cycle Survey. Now, I extend this analysis to look at color ordering within a given color set. For this analysis, the same artificial...

Since I launched my color cycle survey in December, it has collected ~9.7k responses across ~800 user sessions. Although the responses are not as numerous as I’d like, there’s currently enough data for preliminary analysis. The data are split between...

Three years ago, I entered an Ashley Book of Knots Cake into the Johns Hopkins University Sheridan Libraries’ third annual Edible Book Festival. For this year’s contest, I figured I could apply my 3D-printed Hilbert curve microwave absorber research to...

When readily available containers do not come in the desired form factor, 3D-printing can be quite useful. In this case, I wanted a tea bag holder that fit on a small ledge, allowed the tea bag labels to be read,...

A previous post about randomly generating color sets with a minimum perceptual distance addresses the technical aspects of generating sets of colors that are visually distinct for those with normal color vision as well as for those with color vision...

Earlier this year, I released a color cycle picker that enforces a minimum perceptual distance between colors, including color vision deficiency simulations, with the goal of creating a better color cycle to replace the “category 10” color palette used by...

Fused filament fabrication (FFF) 3D printers are good for many things,1 but production of sharp points is not among those strengths. Thus, the traditional structure of millimeter wave absorbers—a periodic array of square pyramids—is poorly suited for production via FFF...

I recently returned from a couple months working in Chile. While there, I finally made it out to see the El Tatio geyser field, which is the third largest geyser field in the world. The geysers are around an 80 km,...

The Scanreference photogrammetry system includes 149 magnetic coded targets and PDFs for printing 192 more targets. However, while measuring something that isn’t ferromagnetic, the magnetic targets aren’t particularly helpful, and the 192 printable coded targets aren’t always enough. Unfortunately, AICON...

The “category10” color palette, originally developed by Tableau, was adopted as the default color cycle for Matplotlib 2.0 and is also used by default by D3.js and Vega, along with other software packages. While more aesthetically pleasing than the old...

Yesterday, I released Pannellum 2.4.0. It doesn’t contain any major new features, although it does finally include translation support, which was an often requested feature. Also included are numerous minor improvements, a few new API functions, and quite a few...

Amazon recently released the Echo Button, a Bluetooth Low Energy device designed for use with Echo devices (which I don’t own). Although it uses Bluetooth instead of Wi-Fi, I thought it might be a better device to repurpose than the...

As part of a Halloween costume (I was a “bright idea”), I designed a light bulb PCB, which was mostly just an excuse to try out PCBmodE. It consists of seven addressable RGB LEDs, an ATtiny85 microcontroller, an ambient light...

While recently in San Pedro de Atacama, Chile, I drove out towards Argentina to look at the national flamingo reserve, which consists of a number of salt lakes (with flamingos). There are also other interesting geologic formations including rocks sticking...

After viewing the total solar eclipse last month, I visited Great Smoky Mountains National Park on the way back from Tennessee, as well as the Cherohala Skyway, parts of the Blue Ridge Parkway, and Mount Mitchell. Here are some photos...

Last week, I watched the total solar eclipse from eastern Tennessee, across the Tennessee River from the Watts Bar Nuclear Plant. I was originally planning on watching it from the mountains on the border between Tennessee and North Carolina, but...

With a total solar eclipse in the continental United States coming up next month, I purchased a solar filter for my telephoto lens. Unfortunately, this OD 5.0 solar filter, which is required for safe optical viewing is much too dark...

Due to extensive trail work over the past two years, new maps of Camp Workcoeman were needed. Furthermore, the Connecticut statewide spring 2016 orthoimagery was recently released, provide a new data source for updating buildings and land cover. As with...

Recently, I’ve been looking at various fiducial markers for computer vision applications. While some of these markers, such as AprilTags, have readily available reference implementations, others have no published code. While one of the markers I was looking at, Pi-Tags,...

Although the OSD3358 system-in-package, the so-called BeagleBone on a Chip, is a BGA package, it turns out that it’s surprisingly easy to solder. Using a stencil, solder paste, and a hot plate, it ended up being easier to solder than...

A few years ago, I wrote about a method of using a modified scanner to scan large documents in segments. While this led to high quality results, it is a very slow and tedious process. More recently, I’ve had a...

Back in September, I took apart the original Amazon Dash, but now there’s a new version, so I took it apart as well. The new product number is PL46MN; the old product number is ORS3YV.1 The original wand was very...