There's No Use Crying over a Podcast

This week, I pinch-hit to write an issue of a favorite email newsletter, Hot Pod by Nick Quah. I discovered it a few months ago, and it is like ambrosia to those like me who want more insight into the broad podcast "industry," especially the parts I don't know in public radio. Nick just got a new job and was going to take this week off, so I offered to write an issue, which you can read here.

Read More

Recent Glenn: Podcasts, Writing, and a Book!

In the spirit of collecting my work across many sites, here's the latest in Glenn!



  • Hey, I have a book! A Practical Guide to Networking and Security in iOS 8 is a guide through all issues with setting up and using networks and encryption/security options for your iPhone and iPad with step-by-step illustration instructions. I managed this revision myself, and since you read this far, you can get 25% off the $15 price for the ebook (no DRM, all major formats included) with coupon code E18CFOG.


Live! Moltz! Minecraft!

On March 3, I did a live event with John Moltz about Minecraft, a subject about which he's co-written a book: A Visual Guide to Minecraft. We talked with an audience about the basics of Minecraft, and the kids present—all experts, including mine!—chimed in with suggestions and feedback. It was a hoot, and you can listen to the fun (and get up to speed on Minecraft) below or download the audio.

Calculating Newtons: The Physics of Force with the New MacBook Connector

The MacBook that Apple unveiled on Monday has a single port. Many connections are gone, but the MagSafe power hookup is the one people are already mourning the most. But I wondered: what if this USB-C connection was designed for a quick pop-out if someone trips over the cord?

I talked to a consulting engineering, an aerospace engineer, a sci-fi author/computer-scientist with a deep scientific background, an industrial designer/manufacturer, and an astrophysicist. The answer? Well, the cable is probably not going to pop out (or shear off) before the laptop is dragged off a surface. But the physics of it are quite fascinating. You can read my whole account at Macworld.

New Ebook! A Practical Guide to Networking and Security in iOS 8

Hey, you can buy this book!

I wrote a book! (Well, a new edition!) If you find yourself in need of step-by-step instructions, troubleshooting, or explanations about using networking options or security features and add-ons in iOS 8 on an iPhone or iPad — do I have a book for you! It's called A Practical Guide to Networking and Security in iOS 8.

It's $15, but you, dear blog reader and friend, receive a whopping 25% off with this coupon: E18CFOG. For that price, you get the PDF, EPUB, and MOBI (Kindle compatible) formats, plus free updates to this edition covering iOS 8. And you can read on any device: I don't believe in encrypted books, because the rights-management locks just hinder legitimate readers. You can also purchase it as a print-on-demand book or via Apple's iBookstore.

It covers AirDrop, AirPlay, Bluetooth, Wi-Fi, WPA2, VPNs, Personal (and Instant) Hotspot, and a lot more, all with friendly instructions and illustrated steps. You can read all about it, including seeing the table of contents and downloading an excerpt at my book site.

(If you bought an earlier version in the Take Control series (covering iOS 4 or 6), look for an email from Take Control Books, as they have a sweet upgrade for previous buyers.)

This is the first book I think I've ever released solo, and it stands on the shoulders of friends and colleagues. The first two editions that I wrote were developed with Tonya Engst and Michael E. Cohen at Take Control Books. This revision, I turned to Jeff Carlson for technical and copy editing and Scout Festa for proofreading. Christa Mrgan designed the cover graphic.

And Tonya and her husband Adam and I are testing releasing books like mine through their Take Control library. Because this book wasn't in high demand, but sold fine, I decided to update it on my own, and they can make it available to their customers, while I can sell it directly too! A win all around.

Recent Writing and Podcasts (mid-January to late February)

On the heels of the news that I'll be writing (and talking) more about Macworld, here's a summary of recent articles and podcasts there and all over.



  • Macworld podcast #445: My first appearance as co-host! We talked about Google's updated Wallet offering with cell carriers, malware in hard drive firmware, solar farms and data centers, and new emoji.
  • Clockwise #75: Apple Car, government spying, Samsung spying, and Apple's greatest threats.

Big Hair to Fill

You may have heard that veteran Macworld staffer Chris Breen joined a fruit company in the Bay Area. (Raisins? Apricots?) Chris spent 30 years as writer, and nearly 20 at Macworld. With him gone, who would fill his big hair…I mean, shoes?

Who has two thumbs and eight other fingers and loves writing about Mac stuff? No, not Two Thumbs Eight Fingers McGee. (I hate that guy.) Me! Because I'm not in California, it didn't work out to take over his job. Instead, in addition to the security and privacy column I've written weekly for Macworld since late September, I'll be co-hosting the weekly Macworld podcast with executive editor Susie Ochs and other Macworld staff, and writing the Mac 911 column, where reader questions are researched and answered. You should subscribe to the podcast right now, shouldn't you?

It's a good shift for me, as a long-time senior contributor for Macworld. I've written…I don't know how many articles for Macworld. Hundreds? It'll be a pleasure to have more recurring gigs there, especially the podcast, as I've been trying to get back into regular audio work. (The podcast I launched with Christina Bonnington, Not Enough Time in the Week, has to go on hiatus, as there's too much of a topic overlap with what we'll be talking about in the Macworld podcast, sadly!)

What does this mean for my other writing? Oh, don't you worry. You'll still find me at Fast Company, the Economist, Boing Boing, and other publications. I have books in progress and a new one coming out this week on networking and security in iOS 8. With the funding nearly complete for The Magazine: The Complete Archives, a combination of my time and outside help will get that out the door by April.

And Old & New, my fresh periodical idea, will still launch as planned: as a blog with commissioned articles and a podcast. I'd always intended to launch it slowly but steadily, instead of all at once with the money and time commitment required for that.

It will be nice to have a solid anchor at Macworld, reducing the amount of time I spend pitching stories, many of which don't turn into assignments, and instead spend more time being productive in a way that benefits other people.

Phase Fresnel Lenses and the Long History of Optics

I file a lot of stories, and very occasionally one doesn't work out. The below explanation of phase Fresnel lenses is one of them. I couldn't hit the right tone for its original destination, and shopped it around, but it wasn't quite a fit anywhere. Enjoy this look into lighthouses, lenses, and the history of optics.

Cape Mears lighthouse in Oregon, now decommissioned and run by volunteers. Photo by yours truly.

Nikon Puts a Lighthouse in Your Pocket

Nikon is at the forefront of techniques to produce complex camera lenses that enable shorter, lighter barrels.

Augustin-Jean Fresnel's crowning achievement was a proof of diffraction that earned him the French Grand Prix in 1819. But it was his later work with refraction in lighthouses that secured him a lasting place on the lips of mariners and theatre stagehands alike. Nikon has taken both aspects of Fresnel's work to produce a new 300mm telephoto lens that is 30% shorter and 40% lighter than its preceding model, while improving all its capabilities.

Fresnel perfected the theory that a lens focuses light passing through it without the need of a continuous curve on the far side: the angle is all that matters. Thus, a lens can be divided into an infinite number of portions of the curve, each of which provides the appropriate focusing path for beams of light. In practice, a Fresnel lens is a set of discontiguous segments, often arrayed in concentric circular ridges, with stepped intervals at each boundary parallel to the direction of the light source.

Fresnel put this theory into wide-scale practice in his role as France's commissioner of lighthouses. Before the use of these lenses, lighthouses both made inefficient use of light, directing roughly 40% from an electric lamp of the day out to the ocean, which would carry weakly from 12 to 20 miles. Larger lenses were more difficult to cast and grind, and hard to transport and mount safely at the treacherous locations at which lighthouses typically sit.

The new lenses under Fresnel's design were not only lighter through the removal of extraneous thickness, but also were constructed in segments, which allowed the use of different kinds of lenses and replacement of individual pieces without losing the entire light. Sigils were designed by rotating a lens around a light with different colored panels, which allowed sailors to identify the origin of each light while far at sea.

Fresnel raised the efficiency to about 80%, while also collimating it long before lasers. A light could be now be seen brightly at over 20 miles (32 km) away. While Fresnel isn't celebrated by sailors the way that Samuel Plimsoll is — for his championing of a line on ships indicating their safe-loading level — he deserves it, too.

Nikon's use of a Fresnel lens also has to do with color, but in a quite different fashion. Normal refractive lenses focus light of different wavelengths at different points, with red (longer wavelength) focusing farthest and blue closest. This causes chromatic aberration, typically corrected with intermediate lenses.

Encyclopædia Britannica, 1911

Encyclopædia Britannica, 1911

However, a phase Fresnel (PF) lens introduces diffraction, as each of the concentric rings of the lens is an obstacles around which light waves bend. This diffraction inverts the chromatic aberration, putting blue closest and red farthest. The concentric rings are spaced at extremely small intervals — tinier than the wavelength of light — to produce the desired diffraction effect.

By pairing a PF element and a refractive element, the combined PF lens corrects the aberration, while reduces the number and weight of lenses and the overall focal distance needed for magnification compared to more conventional lens arrays. In cases of extremely bright spot light sources, a PF lens can cause ring-shaped color flares, and Nikon offers an in-camera software option to mitigate the effect.

The theory of phase Fresnel dates back to at least an academic paper in 1961, and has been applied to X-ray and gamma-ray observation among other purposes. Nikon first experimented with PF over a decade ago, says Steve Heiner, a senior technical manager at Nikon. In that case, the lens was a compact and lightweight small diameter telephoto add-on to a lower-end digital camera.

Nikon also uses a PF lens in some of its microscope products, and competitor Canon introduced a more straightforward Fresnel lens in 2001 that didn't carry with it all the advantages of weight and length.

This new 300mm lens, however, is aimed at the high-end consumer and professional market, where it replaces a fixed (or "prime") telephoto lens that's been a mainstay of Nikon's line for decades, and marks the introduction of phase Fresnel to a bigger, albeit rarified audience. Mr Heiner says the goal was to create a lens with all of the enhancements Nikon had developed over the last two decades as well as reduce the weight and length.

The new model, which started shipping recently as the "AF-S NIKKOR 300MM f/4E PF ED VR" and retails for $2,000, includes a three-axis anti-vibration motor that effectively increases the lens' speed by 4.5 stops, allowing for blur-free photos at slower shutter speeds, among other combinations. For outdoor photographers, the light weight and stabilisation mitigate the need for a monopod or tripod, aiding in portability.

While not a lighthouse in appearance or design, Nikon's news lens is a direct descendent of Fresnel's science — a 21st century realization of a 19th century's genius. And it should take great shots to boot.

iWatch, iHub

I had a vision this morning of where the Apple Watch fits into the bigger universe of things. As I said at the launch, this first version is not what Apple intends to make at all. It will have a highly interested but likely limited audience, and it will make huge margins on the top end of the basic watches plus the premium ones, like gold.

The ultimate form of the Watch comes when it can contain all the sensors and radios of a current iPhone. That's probably within two years — Watch 3. Most of the improvements in battery performance in an iPhone go to power bigger and denser and brighter screens. In a Watch, the power needs for a cellular radio (multiple standards), Wi-Fi, GPS, and MEMS (accelerometer, gyroscope, etc.) will likely be low enough by then and the chips advanced enough to work.

In that view, the Watch stops being an adjunct to a phone, but the pivot point around which the Apple universe turns, which you can see in its use as enabling Apple Pay for some phone models. The Watch becomes:

  • The key to your house, that turns off your alarm.
  • The tracker of your health, which is already planned in the first release.
  • The way you pay, but no longer with a phone.
  • The thing you have and thing you are (biometric) for two-step or two-factor authentication.
  • The entertainment hub for your car, which no longer needs a radio/receiver unit at all, but just a surface-mounted magnetic charging dock against which you place your Watch while driving.
  • What you use to stream and remotely control audio and video to your AirPlay devices.
  • How you unlock your Mac or phone.

HomeKit, HealthKit, Apple Pay, AirPlay, CarPlay, Touch ID, iCloud. The Watch is the digital hub around which everything rotates in the new Apple universe.

A phone, a tablet, a car screen, an HDTV, a monitor, a Mac display — these all become the extensions of the same digital identity that the Watch facilitates managing. You may no longer need a phone, but the focus shift from a phone to the Watch as your pivot point. That's the transition Apple expects to make.