This page is meant to provide a list of references that are directly relevant (marked with a *) or in some cases marginally relevant to the topic of resolution loss in roof prisms and th… Read More

The famous Zeiss “paper” by Weruach and Dörband (attached below) on the development of phase coatings for roof prisms describes a simple… Read More

Many binoculars utilize roof prisms to keep the light along a single optical axis, making for a more compact shape. But the novel geometry of the prism’s reflecting surfaces creates a… Read More

My wife is a wildlife biologist by training and a much better birder than I am. She started as a child, while I didn’t notice birds until I was 26. She has the eyesight of a hawk, whil… Read More

If you are not a fan of painting with a broad brush… If you don’t think babies need to be tossed out with the bathwater… If you don’t like seeing heroic and i… Read More

This is one of the most beautiful results in all of physics, and I find it astonishing that at no point in my decade as a student was it presented or even mentioned. Typically, a formal i… Read More

“Tradition is not the worship of ashes, but the preservation of fire.”― Gustav Mahler Imagine that it is an autumn day in Manhattan, the year is 1869, and a huge party… Read More

The image above pictures Sir Chandrasekhara Venkata Raman. He was a brilliant physicist whose work helps us understand how blue feathers get their color, among many other things. His name is… Read More

The image above pictures Sir Chandrasekhara Venkata Raman. He was a brilliant physicist whose work helps us understand how blue feathers get their color, among many other things. His name is… Read More

I post this with trepidation. I am disinclined to touch on such topics here. A few years ago, I became involved with a birding organization whose core mission of making birding more acces… Read More

I post this with trepidation. I am disinclined to touch such topics here. A few years ago, I became involved with a birding organization whose core mission of making birding more accessib… Read More

Introduction Parabolic microphones are known for their extreme sensitivity, and the origin of their acuity isn’t difficult to guess. It is the most obvious thing about them, which c… Read More

Introduction Parabolic microphones are known for their extreme sensitivity, and the origin of their acuity isn’t difficult to discern. It is the most obvious thing about them, which… Read More

Diffraction patterns and resolution In the previous post we traced the passage of light through a roof prism, which required decomposing vectors into components, accounting for phase shif… Read More

Diffraction patterns and resolution In the previous post we traced the passage of light through a roof prism, which required decomposing vectors into components, accounting for phase shif… Read More

Phase shifts and interference The previous post introduced the topic of roof prism performance loss resulting from phase shifts that accompany total internal reflection (TIR). These shift… Read More

Phase shifts and interference The previous post introduced the topic of roof prism performance loss resulting from phase shifts that accompany total internal reflection (TIR). These shift… Read More

Introduction Some time ago, I began a fruitless search for a detailed treatment of the performance losses endemic to roof prisms, and the so-called “phase coatings” that recti… Read More

Introduction Some time ago, I began a fruitless search for a detailed treatment of the performance losses endemic to roof prisms, and the so-called “phase coatings” that recti… Read More

Honored to be mentioned alongside a number of great birders that are featured in the New York Times this weekend: LINKThe post The New York Times: “Birds Are My Eyesight” first a… Read More

Honored to be mentioned alongside a number of great birders that are featured in the New York Times this weekend: LINK Read More

I’ve written a technical article on the topic of why the roof prisms used in binoculars require specialized coatings in order to improve their performance. I was prompted to pull this… Read More

I’ve written a technical article on the topic of why the roof prisms used in binoculars require specialized coatings in order to improve their performance. I was prompted to pull this… Read More

When I was twelve I discovered astronomy and made my first optics purchase, a cheap, awful refracting telescope made by the K-mart subsidiary Focal. I knew I needed a more serious instrument… Read More

During the winter I made the jump to 32-bit audio recording with the Zoom F3 field recorder. I couple this with a Sennheiser MKH 416 shotgun microphone. I’d originally purchased the Ro… Read More

(Update: I changed microphones.) During the winter I made the jump to 32-bit audio recording with the Zoom F3 field recorder. I couple this with a Sennheiser MKH 416 shotgun microphone. I… Read More

I used to think that travel to the tropics during rainy season would be a waste of time and money, and so for many years we timed our trips so as to miss the wettest months. But while we wer… Read More

The first time I put a bird on a list, it was the spring of 1993, and the entry was Northern Flicker. A common bird in a city park, an unlikely spark of obsession. Thirty years later, to the… Read More

I invested in a better USB microphone to replace the $18 Cmteck desktop unit that I used for my first swag at the BirdNET Pi. I wanted an omnidirectional microphone with a 24-bit, 48 kHz ADC… Read More

I have a Raspberry Pi that I’ve been tinkering with for years, learning its personality while looking for a useful, novel application for it. I can now report that it is employed full… Read More

After finishing up in Argentina, we wanted to break up the trip back north to the US. Colombia is perfectly positioned for this: with Bogatá being only about six hours from Buenos Air… Read More

After our trip to Tierra del Fuego and cruise to Antarctica, we flew from Ushuaia to Córdoba, Argentina to start a nine-day trek from the north-central region all the way north to the… Read More

We had first visited Argentina in 2016, with a week or so based out of Buneos Aires. There is plenty of great birding within a few hours of the capital, but after finishing that trip we want… Read More

We recently took a nine-day cruise on the Ocean Victory, from Ushuaia, Argentina, to the South Shetland Islands and Antarctica. In terms of birding it was a trip for quality, not quantity. I… Read More

Preconceived ideas about people, their tastes, and their expected behaviors, come readily. Few would expect a disabled old physics nerd like me, who typically prefers Mahler symphonies and W… Read More

Lately I’ve been thinking about doing a bird outing where every species that I tick – whether I see it or hear it, or both – must have accompanying media capturing it. Phot… Read More

Our backyard is typically very active with birds, especially juncos this time of year. There are plenty of feeders and spilled seed to keep everyone happy. Mid-morning today, Claire exci… Read More

Well, this is well outside of my normal comfort zone, but I will be heading to New Jersey in May to participate in the World Series of Birding. For almost 40 years, the WSB has raised mon… Read More

Scanning the snowy ground around our house today, as I am wont to do every hour or so, in hopes of finding a redpoll or some new visitor, I glanced at a medium-sized, dark bird on the ground… Read More

Suppose you’ve just set up a last-minute trip for birding in Manuas, Brazil. It will be your first time in that diverse region, which sits on the border of Amazonia and the Guianan Shi… Read More

This was our Return To Peru Trip: to finish an adventure that the March 2020 COVID-19 lockdown had wiped out. In March of 2020, we flew to Peru with the intention of doing a long, two-par… Read More

My eyes are terrible, and I rely on ear-birding to make up for it. I’ve always thought of my hearing as being good, other than having some obnoxious tinnitus resulting from decades… Read More

When I was much younger and had normal eyesight, I worked as a line cook. I enjoyed the mental and physical challenge of handling dozens of orders at once. You had to constantly think a… Read More

It is now Birdability Week! Monday 18th – Sunday 24th October, 2021. It is meant to celebrate birders with disabilities or health concerns and to help the birding community improve acc… Read More

This weekend we drove from the Twin Cities up to the eastern end of the U.P. of Michigan. To go look for a life bird that is rather hit-or-miss in northern Minnesota, but per eBird, very con… Read More