The Daily Parker

Politics, Weather, Photography, and the Dog

Are more megapixels inherently good?

I debated this question with someone at a dinner a couple weeks ago. She suggested higher megapixel numbers told you more about the ego of the camera buyer than about the quality of the images.

I said it depends on how you're using the photos, but generally, more data yields more useful photos.

Here's an illustration, using a vaguely-recognizable landmark that I happened to pass earlier this weekend, and just happened to have photographed with three different cameras. All three photos are from approximately the same location at approximately the same time of day. Obviously there are some differences, but the illustration should work regardless.

Let's take a look at three images stored as 600x900 JPEGs and displayed at 500x750, the standard size for this blog. First, let's see one from a Kodak DC4800 in February 2001, 13 years ago. The original size was 1440x2160 at 3MP:

Now skip forward to August 2009, using a Canon 20D shooting a 2336x3648 JPEG at 8 MP:

Finally, two days ago, using a Canon 7D shooting raw at 3456x5184 (18 MP):

The photos look pretty comparable at this resolution, don't they? So let's zoom in on a 150x150 pixel view of each:

So each one has successively more data than the previous, which becomes obvious when you zoom in.

Another difference: I shot the one from this weekend using the raw format, which preserves all of the information the camera had available at the time of the photo. JPEG images are lossy; they always leave some information out. And because raw images are easier to manipulate using software, I was able to make the third photo a little bit better than I could make the other two.

So are more megapixels more useful? Not if you're just putting up blog posts, but for serious photography, absolutely.

Weakest link in the chain

I had planned to post some photos tonight showing the evolution of digital cameras, using a local landmark, but there's a snag. The CF card reader I brought along isn't showing up on my computer, even though the computer acknowledges that something is attached through a USB port.

As I'm visiting one of the most sophisticated and technological cities in the world, I have no doubt I can fix this tomorrow. Still, it's always irritating when technology that worked a few days ago simply stops working.

For those doubting my troubleshooting skills, I have confirmed that the CF card has all the photos I shot today; that the computer can see the CF card reader; and that the computer can connect effectively to other USB attachments. The problem is therefore either in the OS or in the card reader, and I'm inclined to suspect the card reader.

Ten weeks later

When we got a few centimeters of snow on December 29th, no one expected it would still be on the ground after we changed the clocks in March. Yet there it is, officially 50 mm for the last 24 hours.

The 11am temperature at O'Hare was -0.6°C, and the forecast calls for the temperature to pop up to 7°C this afternoon and then stay above freezing until Tuesday night—possibly even getting up to 14°C tomorrow afternoon. If the little snow we've still got can survive that onslaught, then I will be impressed.

And the best part about this forecast? I won't write anything more about how many consecutive days of snow we've had. You're welcome.

Snow-cover reports come out every six hours. (The next report is due at 1pm.) I'll post as soon as the ground is officially snow-free.

Just one more moan: It's 18°C and sunny in London. But I won't be there for almost two more weeks.

Update: At 1pm the official snow depth was still 50 mm, but the temperature was up to 2°C. I'll check back in six hours.

Down to a Sunless Sea

Someone forwarded me a year-old short story by Neil Gaiman the Guardian published last spring. It begins:

The Thames is a filthy beast: it winds through London like a snake, or a sea serpent. All the rivers flow into it, the Fleet and the Tyburn and the Neckinger, carrying all the filth and scum and waste, the bodies of cats and dogs and the bones of sheep and pigs down into the brown water of the Thames, which carries them east into the estuary and from there into the North Sea and oblivion.

It is raining in London. The rain washes the dirt into the gutters, and it swells streams into rivers, rivers into powerful things. The rain is a noisy thing, splashing and pattering and rattling the rooftops. If it is clean water as it falls from the skies it only needs to touch London to become dirt, to stir dust and make it mud.

Read the rest here.

About this blog (v 4.2)

Parker, 14 weeksI'm David Braverman, this is my blog, and Parker is my 7½-year-old mutt. I last updated this About... page in September 2011, more than 1,300 posts back, so it's time for a refresh.

The Daily Parker is about:

  • Parker, my dog, whom I adopted on 1 September 2006.
  • Politics. I'm a moderate-lefty by international standards, which makes me a radical left-winger in today's United States.
  • The weather. I've operated a weather website for more than 13 years. That site deals with raw data and objective observations. Many weather posts also touch politics, given the political implications of addressing climate change, though happily we no longer have to do so under a president beholden to the oil industry.
  • Chicago (the greatest city in North America), and sometimes London, San Francisco, and the rest of the world.
  • Photography. I took tens of thousands of photos as a kid, then drifted away from making art until early 2011 when I finally got the first digital camera I've ever had whose photos were as good as film. That got me reading more, practicing more, and throwing more photos on the blog. In my initial burst of enthusiasm I posted a photo every day. I've pulled back from that a bit—it takes about 30 minutes to prep and post one of those puppies—but I'm still shooting and still learning.

I also write a lot of software, and will occasionally post about technology as well. I work for 10th Magnitude, a startup software consultancy in Chicago, I've got more than 20 years experience writing the stuff, and I continue to own a micro-sized software company. (I have an online resume, if you're curious.) I see a lot of code, and since I often get called in to projects in crisis, I see a lot of bad code, some of which may appear here.

I strive to write about these and other things with fluency and concision. "Fast, good, cheap: pick two" applies to writing as much as to any other creative process (cf: software). I hope to find an appropriate balance between the three, as streams of consciousness and literacy have always struggled against each other since the first blog twenty years ago.

If you like what you see here, you'll probably also like Andrew Sullivan, James Fallows, Josh Marshall, and Bruce Schneier. Even if you don't like my politics, you probably agree that everyone ought to read Strunk and White, and you probably have an opinion about the Oxford comma—punctuation de rigeur in my opinion.

Thanks for reading, and I hope you continue to enjoy The Daily Parker.

More evidence that David Cameron is a stooge

Shortly after my last trip to London I blogged that UK Prime Minister David Cameron's crowing about Britain's economic recovery entirely missed the point of how awfully and slowly that recovery was going. This morning Krugman freshens the evidence:

A couple of weeks ago I tried to get at what’s wrong with the latest tactic of the austerians in terms of a classic Three Stooges scene. Curly is seen banging his head against the wall; when Moe asks why, he replies, “Because it feels so good when I stop.”

As Simon Wren-Lewis tries to explain, this is exactly the basis of the Cameron government’s triumphalism now that UK GDP is growing again.

The basic fact of UK economic performance since the financial crisis is that it has been terrible — in fact, as the NIESR documents, GDP performance has been substantially worse than during the Great Depression.

It's tragic, really. The only question going into the May 2015 elections will be: do Britons understand how much better off they could have been?

The Weird Economics Behind London's Disappearing Pubs

From The Atlantic Cities blog:

Over the past decade, 1,300 London pubs have emptied their cellars and wiped down their tables for the last time. It's not just obscure, unloved bars that are dying. This winter, two well-known historic pubs, both open for over a century apiece, will likely be turned into private housing. One is the Old White Bear, a red-brick building hidden away in village-like Hampstead, a former spa town swallowed up by Victorian London. The other, just down the hill, is The Star, an inn dating back to the 1820s with a wood-lined interior (featured in this 1980s pop video) that makes drinking there feel rather like sitting inside a whiskey-soaked violin.

Under the British system, the pub "landlord" (in British pub terminology, this actually means a manager that rents a premises, rather than an owner) must buy their booze from the company they rent the pub from. With no competition, the prices they pay are generally inflated, meaning that even if landlords trim their profit margins, beer still comes out pricier than it otherwise needs to be. While pub companies turn a profit, individual landlords are pushed to the wall. The pub companies then sell off under-performing premises, even though pubs wouldn't actually be unsustainable if landlords got a better deal.

There's a silver lining, and not just from pubs like Southampton Arms: The City of London has taken steps to preserve some landmark pubs.

Problems with Boris Bikes?

The Atlantic Cities blog sounds the alarm about London's bike share program:

While the system recorded 726,893 journeys in November 2012, last month there were only 514,146. To cap these poor user figures, today Transport for London announced that the scheme's major sponsor, Barclays Bank, will pull out of its sponsorship deal in 2015. Given the bad publicity the system has received recently, it may be hard to find a replacement sponsor without some major changes.

None of this would matter much if London’s scheme was entirely self-sustaining. But while Paris's bike-share scheme actually makes money for the city, London's 4,000 bikes cost local taxpayers an average of £1,400 per bike per year. As the Daily Mail points out, this would be enough to buy each of the scheme's 38,000 registered users a £290 bike. Barclays has thus found its sponsorship deal a mixed publicity blessing – though the bank itself may be part of the problem. The £50 million it promised was never going to be enough, and the amount it has actually handed over so far suggests their ultimate contribution could be at little as half that.

So, Toronto and London are having problems; Chicago and Paris are booming. This is turning into a fascinating natural experiment.