Follow Slashdot blog updates by subscribing to our blog RSS feed


Forgot your password?

Comment In other news, 4 is greater than 1 (Score 2, Insightful) 875

Just for gigles, go look at gapminder. See$majorMode=chart$is;shi=t;ly=2003;lb=f;il=t;fs=11;al=21;stl=t;st=t;nsl=t;se=t$wst;tts=C$ts;sp=6;ti=2006$zpv;v=0$inc_x;mmid=XCOORDS;iid=phAwcNAVuyj1jiMAkmq1iMg;by=ind$inc_y;mmid=YCOORDS;iid=phAwcNAVuyj1gkNuUEXOGag;by=ind$inc_s;uniValue=8.21;iid=phAwcNAVuyj1NHPC9MyZ9SQ;by=ind$inc_c;uniValue=255;gid=CATID0;iid=pyj6tScZqmEfbZyl0qjbiRQ;by=grp$map_x;scale=log;dataMin=294;dataMax=76977$map_y;scale=log;dataMin=-1.2196;dataMax=26$map_s;sma=58;smi=1$cd;bd=0$inds=;modified=6 Your argument is a bit silly. It it like a glutton complaining that his neighbors their 3 children eat more than he does, so they should be the ones to go on a diet. Yes, 1.32 billion Chinese use more energy than 0.31 billion Americans. Are we so special that we deserve 4x the CO2 per capita as the rest of the world?

Comment Re:I have an alergy to dreadful 3D (Score 1) 495

I had roughly the same experience. But during Avatar, there where a couple of moments where I seemed to have a '3D overload' where I took off the glasses for about 30 seconds. I wonder if I could get accustomed to 3D movies and have this effect go away. Many other fatiguing activities become easy with practice.

Comment IE9 on SVG Test Suite (Score 2, Informative) 152

If you look at Haavard's blog on the Opera site, you will find a reference to run of the SVG 1.1 Test Suite on IE9. In contrast to Microsoft's SVG test suite (of about 104 individual tests in 7 areas), the W3C's test suite has 275 tests, each of which typically has a dozen or so subtests. On the standard test, IE9 passed 28.36 % of the tests. All other browsers are above 60%. Once SVG becomes viable, I expect that all of the other browsers will quickly advance into the 90%+ range. Opera is already well above 90%. So I welcome IE9 into the SVG crowd, but they are far behind the competition.

A skeptic, that is to say, anyone who can recall Microsoft's behavior over the past 20 years, might wonder if Microsoft ran the official SVG test suite on all competing browsers to find areas where they failed. They then built a second test where they know the others will fail. The developers then focused on implementing them correctly in IE9. This would give them bragging rights when they ran their specially crafted SVG test that focussed on these areas. But it would not help improve interoperability if they grade themselves on a new test, rather than the W2C test suite. I hope I a wrong, but like the little boy who cried wolf, Microsoft has a history of misleading the community.

Comment You don't seem to understand 'gap' (Score 1) 192

The gap in a semiconductor is a gap in quantum energy levels. iIf you have a gap of 0.9 eV, a photon with 0.8 eV strikes the sensor, it basically undetectable. If a photon has enough energy, it is detectable. It isn't quite that simple, photons have spin, so you have to have a the electron states with different spins in order to detect the photon.

A CMOS sensor is smooth and fairly reflective, so it reflects a considerable fraction of the light. This reflected light does indeed cause flare. The second article states that the new sensors are black, so this new sensor could dramatically reduce flare.

Comment Sounds like Baker-Nunn camera (Score 1) 192

You say you want more portable glass. However, you're still asking for a 700mm lens. You do realise, that in order to have 700mm lens at f/1, you need an entrance pupil with 700/1 = 700mm worth of diameter? Yup, that's right, 70cm of diameter in order to achieve f/1. Not sure that's ever going to be portable, mate.

To quote Frank Abagnale Jr., "I concur."

From wikipedia: (

A dozen f/0.75 Baker-Nunn cameras with 20-inch apertures – each weighing 3.5 tons including a multiple axis mount allowing it to follow satellites in the sky – were used by the Smithsonian Astrophysical Observatory to track artificial satellites from the late 1950s to mid 1970s.

20 in *25 mm/inch = 500 mm. => 500 mm /0.75 = 667 mm Objective, which is pretty close to 700mm. At 3.5 tons, this is only semi-portable.

Comment Re:They're black! (Score 3, Interesting) 192

this is not an issue of resolution. This is an issue of of contrast. For example, a reflecting telescope w an 8 inch mirror will out resolve a 4 inch refractor. But the refractor's image of the moon will have dramatically more contrast.

If you point any of those cameras toward the sun, you will see flare. This is carefully explained in the video. To suppress flare, you need to stop reflections. On the glass, you can multilayer coatings. On the sensor, you can't do that. So you have to live with the reflection. If you have a concave lens element facing toward the camera body, you have a little concave mirror just waiting to reflect the specular reflection of the sun back onto your sensor. If the new sensors are black, they are not going to reflect much - so less flare.

Comment Re:Doesn't mean much as long as the optics still s (Score 1) 192

You are talking about the Canon 300mm f/2.8 lens, which is a legend. The optics date back to the early 70's. One of these took a picture of Henry Kissenger that was so sharp you could read his classified document. It only costs a bit over 4 grand. The MTF function for this lens it just crazy good, see

The Canon 85mm f/1.2 is also a legend. And only about 2 grand.

If these lenses are only 'pretty good', you must be accustomed to the optics in research telescopes ;-)

Slashdot Top Deals

What hath Bob wrought?