Category: Miscellaneous

Eyeballing the iPad 3 retina display

By Phil Plait | March 7, 2012 2:06 pm

Today, Apple announced the new iPad 3, which has a bunch of new features and improvements over the iPad2. One of the new features is a much higher resolution display: 2048 x 1536 pixels, which they advertise as a "retina" display: ad-speak for pixels so small your eye can’t see them. The display looks smooth and unpixellated.

But is that really the case? I did a little math and found this claim to be true, more or less. But there are some caveats, and they’re interesting.

[By the way: I’ve done the math here in imperial units, and not metric, because that’s the standard the industry uses for pixels and such. Silly, but it’s one of the last holdouts you’ll see used this way.]

iBalling the numbers

First, you should really read my post Resolving the iPhone resolution, where I first dissected the "retina display" claim for when the iPhone 4 came out. My conclusion then was that yes, the iPhone 4 display has pixels so small you can’t see them under normal circumstances. But in that post I did a bit of math to prove it.

What I found was that if you hold a device about a foot away from your face and have normal vision, the pixels need to be smaller than 0.0035 inches in size for them to be unresolved; in other words, pixels at this size or smaller give you a "retina display". The iPhone 4 has pixels about 0.0031 inches in size, so it wins.

But what about the new iPad?

Ah, iSee

The new iPad is reported to be the same size as the iPad 2, with a display of 7.75 x 5.8 inches. But it does have smaller pixels than the old version! Dividing the size of the display by the number of pixels (2048 x 1536) we get a pixel size of 0.0038 inches (or 264 dots per inch, if you prefer).

Uh oh. That’s actually a bit bigger than what your eye can see! So is this truly a "retina display"?

Well, let’s not be too hasty to poo-poo this new tech. For one thing, the iPad display is only resolved if you hold it a foot or closer to your eyes. After a little testing, I found that I tend to hold my own iPad 2 about 15 – 17 inches from my face. From that distance (let’s call it 16 inches), pixels need to be smaller than 0.0047 inches to be unresolved (again, see my old post about how that works and where that number comes from), and the iPad 3’s pixels are certainly smaller than that!

If you do happen to have perfect eyes, under ideal circumstances you’ll probably be able to see the pixellation in the screen, but it won’t be that big a deal, I’d wager — and if you hold the iPad 3 about 18 inches from your face, the pixels are too small to see in any case. So, for the majority of people, the claim of a "retina display" is probably accurate.

I’ll note, though, that the iPad 3 pixels are larger than those for the iPhone 4. But that’s OK; I tend to hold the iPhone a little closer to my eyes than I do the iPad. In either case, I’m unlikely to see the pixels.

I imagine there will be a lot of writing about the display for the iPad 3, with some people loving it and others hating it — that’s inevitable when new tech comes out, especially when Apple is behind it (I’ll note my original resolution post was in response to what I thought was an unfair denigration of the iPhone 4’s display). Incidentally, Boing Boing reports the new iPad will have 40% more color saturation. A display with more colors can trick the eye into thinking the resolution is better, so this will also help the "retina display" claim.

And yes, duh, of course I want one! But I tend not to jump into new tech, and besides, I got the iPad 2 just a few months ago. I like it, and it’s fine for me; the new features are not anywhere near enough for me to want to spend the money to upgrade. Hopefully, my iPad 2 will last long enough that when the iPad 4 comes out, by then I’ll be ready.

Image credits: Apple; wikipedia. Note: I had incorrectly called this a "retinal display", so I have corrected the text. Thx to huggyb for pointing this out.

Related Posts:

Resolving the iPhone resolution
Moon Hoax: Why not use telescopes to look at the landers?
My New Years Resolution

Science Getaways: Update

By Phil Plait | February 7, 2012 9:36 am

I love science. OK, duh, but I really do. And when I go on vacation, I can’t help but see science everywhere, and in every case it makes the trip more fun for me. Seeing local geology, biology, how the stars might look different at a different latitude… it adds to the vacations, makes it better.

That’s why my wife and I started a company called Science Getaways. We figured there are lots of other folks out there like us who would really enjoy taking a vacation that has bonus science added in. Our first planned trip is to a gorgeous Colorado dude ranch called C Lazy U. Besides the usual amenities of such a place — horseback riding, great food, spectacular views of the Rocky Mountains — we’re adding SCIENCE! And scientists: we have a geologist, a biologist, and an astronomer — hey, me! — who will be on hand to give talks about the local nature scene, and then we’ll take hikes to put that new-found knowledge to practical use. I’ll be running a stargazing session every evening with my new 8" Celestron telescope, and I’m hoping to do some solar observing during the day as well.

IMPORTANT NOTE: We’ve negotiated a special rate — the price we’re offering is actually less than the usual ranch rate. We’re hoping to have the entire ranch for our group, but if we don’t have enough reservations by March 1 we can’t guarantee it. Space is limited, so please book now if you plan to come.

By the way, we’re also on Facebook and Google+ if you’d like to add us.

I hope to see lots of BABloggees there!

Related posts:

Science Getaways

Get Scott Sigler's The MVP for $3 off

By Phil Plait | February 4, 2012 11:12 am

Wanna get Scott Sigler’s brand-spankin’ new novel The MVP for three bucks off? Read on…

Scott is a pal of mine, but he’s also a few other things… like a NYT best selling author, for example. His science-based horror books like Infected, Contagious, and Ancestor are really fun (and ookie) reads. He’s been writing a really good science fiction sports series of novels about the Galactic Football League, where humans play football side-by-side with aliens… who may be able to leap five meters in the air, run far faster than humans, and oh yeah: also might possibly want to eat the other team.

His new book in the series, The MVP, is available for pre-order starting right now! And because I am super special and wonderful and love my readers, if you pre-order the book with the coupon code badastro you get $3 off the price!

Just go to his site, order the book, and put badastro into the coupon code field to get the discount. This code also works on his other hardcovers in the GFL series, including The Starter and The All-Pro (the first novel in the series, The Rookie, is sold out of hardcover, but you can still get it as an ebook or an audiobook – when the hardcovers are gone, they’re gone.)

But why trust me? You can listen to Sigler himself barking at you about this:

Full disclosure: I get a kickback from this, but I’d tell you to buy his books anyway. Why? For one thing, they’re lots of fun. For another, Scott is an independent author, who sells these books on his own, without a publisher, and I’m all for that. It’s no exaggeration to say that he helped invent online publishing; he couldn’t find a publisher for his first book, Earthcore, so he audiocast the whole thing and gave it away for free. This was back when the word "podcast" was brand new, and Scott was way, way ahead of the curve. He turned that idea into a revolution of online publishing, loosening the stranglehold of publishing houses on books, and I honestly think we’re better off for it.

So if you buy his books you are supporting a talented writer, an indy publisher, a revolutionary, and I can afford to keep myself in Tootsie Rolls for the rest of the year.

Go buy his stuff now!

CATEGORIZED UNDER: Cool stuff, Miscellaneous
MORE ABOUT: GFL, Scott Sigler, The MVP

Holiday fundraisers

By Phil Plait | December 12, 2011 7:00 am

Winter is always a big season for charities. Christmastime is traditionally a time to give, but that means competition among charities increases, and it’s hard to separate out which ones you want to give to. And some "traditional" charities seem like they do good work, but have some pretty intolerant and bigoted beliefs they keep relatively quiet. So deciding to whom to give can be difficult.

So if you have a few bucks, here are a handful of charities I like.

Recipe4Hope is campaign to raise money for the Autism Science Foundation. I am very wary of groups claiming to research autism, since so many of them are fronts for anti-vaccination promoters. ASF, though, understands that vaccines do not cause autism, and is looking into actual scientific research. Here’s their video for this year:

100% of the donations will fund ASF’s pre- and post-doctoral autism research fellowships, helping young scientists start their career researching autism. They have a donation page set up, and the campaign runs through the end of 2011.

The James Randi Educational Foundation has an annual Season of Reason campaign which raises funds to keep JREF operating. Donate $100 (or sign up for $25/month or more) and they’ll send you a SurlyRamic ornament! The JREF has really ramped up their educational efforts over the past couple of years, and your donation will go toward teaching people the critical thinking that is so, well, critical to making important decisions.

I already wrote about Astronomers Without Borders recently, and while the Sky Safari campaign is over, they’re still accepting donations! AWB does great work, reaching out across the world to educate people about the night sky, trying to unite everyone through a love of astronomy.

Foundation Beyond Belief is a secular group that picks 10 needy causes every quarter and gathers funds for them. They don’t necessarily exclude religious charities, but they do choose them based on compatibility with humanist goals, and they have a specific program called Challenge the Gap, which promotes finding common ground between theists and atheists, something I obviously think is a noble and worthwhile goal.

Got some charities you like? List them in the comments!

CATEGORIZED UNDER: Miscellaneous, Religion, Skepticism

News quickies, part n

By Phil Plait | September 2, 2011 12:02 pm

Just some quick notes, to fill my quota give you some interesting reading:

1) Scientific American has a great article online about why it’s important to vaccinate, and how to talk to parents about it. [via George Valenzuela]

2) Speaking of which, the Autism Science Foundation — a non-profit that supports real research into autism, instead of trying to link it to vaccines despite all the evidence — was chosen as the number 1 startup charity in the "Disabilities" category by Philanthropedia/Guidestar. Congrats to them! [via Dawn Crawford]

3) The Discovery Institute isn’t completely honest? Unpossible!

4) Bill Nye helps create a sundial at Cornell University that glows when the Sun reaches its daily peak in the sky. [via Beth Quittman (my agent!)]

5) Frying pans that look like planets. Seriously. Very cool.

Help me get a panel at SXSW!

By Phil Plait | September 1, 2011 12:00 pm

SXSW (or South by Southwest if you want to make it easier to say out loud) is a major geekapalooza held every year in Austin, Texas. There’s music, film, and lots and lots of tech nerdery. I’ve wanted to go for a long time.

Now’s my chance, but I need your help! I was contacted by Stephanie Smith at JPL who is proposing a panel called "2012: You Bet Your Asteroid the World Won’t End", featuring JPL’s Veronica McGregor, near-Earth asteroid expert, Don Yeomans, and me. The panel would be about end-of-the-world scenarios, something about which I have plenty of fun things to say.

The thing is, the panels have to be voted on, and that’s where you come in. All you have to do is go to the SXSW panel picker, register (that only takes a sec), and then you can vote for what is undoubtedly the best panel out of the 3285 listed.

If you do, I will love you forever and send you a unicorn*. But please hurry — voting closes at noon Central (US) time on Friday, September 2. Thanks!

* Offer void where unicorns exist.

CATEGORIZED UNDER: DeathfromtheSkies!, Miscellaneous
MORE ABOUT: doomsday, SXSW

Putting the eye in Irene

By Phil Plait | August 25, 2011 9:26 am

Over the past few days, hurricane Irene has grown as it approaches the United States. The NASA/NOAA Earth-observing GOES 13 satellite has been keeping an eye on the storm, and images it has taken have been put together into this dramatic video showing Irene from August 23 at 10:40 UTC to 48 hours later… just a few hours ago as I write this:

Pay attention about 20 seconds into the video (August 23 at about 20:00 according to the clock at the top of the video). You can see the eye wall region burst into existence, and a few seconds later the eye itself suddenly appears. Also, a surge of white clouds appears to the right of the eye and wraps around the hurricane. That’s where warm air has risen strongly, overshooting the cloud tops, and producing intense rainfall (5 cm/hour according to TRMM!). Overshooting tops, as they’re called, happen frequently in tropical storms as they intensify. For what it’s worth, something like that happens in stars as well as hot plasma rises rapidly from under the surface, though astronomers tend to call it "convective overshoot".

Irene is currently a strong Category 3 hurricane (with sustained winds at 200 kph (120 mph)), and is expected to start affecting the east coast today. If you live along the coast, take precautions, and please, stay safe.

Video credit: NASA/NOAA GOES Project

CATEGORIZED UNDER: Miscellaneous, Pretty pictures

A tsunami's icy reach

By Phil Plait | August 14, 2011 7:09 am

The March 2011 earthquake and subsequent tsunami off the coast of Japan did unimaginable damage. The tsunami was several meters high, marching a long way inland, and wiped out entire towns.

It also swept out to sea, expanding across the planet. By the time it hit the Antarctic ice shelf — 13,000 km away, taking less than a day — it was well under a meter high. But water is dense (a cubic meter weighs a ton!) and that much of it hitting the ice can cause it to flex and break.

And that’s precisely what happened:

[Click to antarcticenate.]

That’s the Sulzberger ice shelf on the coast of Antarctica and the Ross Sea. A few days before this image was taken those gigantic blocks of ice were still part of the shelf (though cracks were already present), and in fact the big one had been part of the shelf for over four decades at least. The pounding wave of the tsunami broke up the shelf, sending those blocks into the sea.

Mind you, that big rectangular block of ice is about 11 km (6.6 miles) across — about the size of Manhattan! The total ice broken off probably doubles that amount. It was about 80 meters (260 feet) thick from top to bottom, too, so we’re talking a lot of ice — about 100 billion tons worth all told!

This image, but the way, is not an optical photo. It’s actually a radar map from Europe’s Envisat Earth-observing satellite. Radar bounces off of water differently than it does off ice, distinguishing the two in images. Maps like this are critical in understanding how the ice changes in the south polar regions, and that of course is critical in understanding the changing environment of our planet.

[Note: after I drafted this post, I found that NASA made a video explaining it:

Nice, and really shows how massive this event was.]

Related posts:

Ice island heading south off Labrador
Enormous glacier calves in largest arctic even seen in 48 years
As arctic ice shrinks, so does a denier claim
Sign of the apocalypse: blood waterfalls

CATEGORIZED UNDER: Miscellaneous, Pretty pictures

Boulder fire damage seen from space

By Phil Plait | August 3, 2011 7:00 am

As I write this, storm clouds are gathering in the west. That’s a pretty common situation here in Boulder, Colorado, in the summer. We get fine, clear mornings, and sometimes rain in the afternoon. In general big storms aren’t exactly rare, but this summer we’ve been getting pounded. On my bike rides it’s been routine to see the creeks in the area swollen to the point of overflowing.

But this summer, that situation has turned more dangerous. We’ve been getting some serious flood scares, and the reason may not be obvious to people who don’t live in the area: fires.

Last year, the Fourmile Canyon area north and west of Boulder burned pretty vigorously for many days. The smoke plume was visible from space, and it caused a lot of local grief. What wasn’t clear to me at the time was how this would affect flooding.

The image above, taken on June 7, 2011, is from NASA’s Earth Observing-1 satellite, and is a combination of far-infrared and visible light. Water (reservoirs and lakes) shows up as purple in this false-color image, vegetation is mostly green, and red/orange shows the fire damage. You can see Boulder to the lower right of the burned area.

When fire burns off all the plants, there’s nothing to hold the rain water in when we get storms. The water all washes downhill, in this case into the Fourmile Creek. That runs into the Boulder Creek, and that, well, here’s a natural color image which shows why that’s bad:

Read More

CATEGORIZED UNDER: Miscellaneous, Pretty pictures

Music of the spheres

By Phil Plait | July 24, 2011 7:00 am

Alex Parker is an astronomy PhD student at the University of Victoria, and had a neat idea: create music based on 241 supernovae found in a three-year-long survey of the sky. The data were from the Canada-France-Hawaii-Telescope, and he made a video of the effort:

Each note represents one of the supernovae. The volume is based on the star’s distance, and the pitch based on how long it took the supernova to rise to maximum brightness and fade away — that’s tied to the exploding star’s total energy released, and was the key factor used to discover dark energy — together, they are combined into this "Supernova Sonata". Clever, and cool.

Speaking of which, I also got an email from Mike Lemmon of Neue Music. For a website called Experience the Planets, he created music I’d characterize as "atmospheric" — more tonal and ethereal than most synth music. I happen to like this kind of stuff, and I find myself listening to his "Planets" as I’m working. It’s not for everybody, I know, but if you like that kind of thing as I do you should give it a shot.

It’s available on iTunes, or you can go to the link above and listen while thumbing through some incredibly beautiful artwork of the planets.

CATEGORIZED UNDER: Astronomy, Cool stuff, Miscellaneous

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