PakledHostage

Nope. And isn't that a bit too general? I'm hoping for... for... ah heck I don't know... MrMuddyBoots

This is something of a silly argument because we're comparing apples and oranges, but Lajos' point is valid. The article talks about OSIRIS's dynamic range and its 16-bit ADC. In that regard, the OSIRIS camera is still a better camera than a modern high-end DSLR. As I mentioned in my post on the previous page, my camera's very recent technology DIGIC 5+ image processor only has a 14 bit ADC. Although my camera isn't a top of the line DSLR camera, the same DIGIC 5+ image processor is used in Canon's current crop of top of the line cameras like the 5D Mark III and 1D-X. My camera, like all DSLR cameras, struggles to correctly expose shots that contain a combination of very bright and very dark areas. You can compensate by adding filters and/or by stacking multiple shots to create a HDR image, but my read of the various references suggest that OSIRIS does a better job natively. It is this combination of OSIRIS's image processor's 16-bit resolution ADC and the dynamic range of the sensor that make it impressive for its age.

I sometimes lurk. Depends on whether or not there's anything interesting going on on the other threads and how bored I am.

Right here?

Nope. How about Lhathron the Elf? Green dot says s/he's online now.

You need to look at the article that Lajos linked to. There are details in it about the camera's dynamic range. Despite being 10 years old, the article says that the Osiris camera is a 16-bit camera. I assume, by that, that they mean it uses a 16-bit ADC to acquire analog data from the camera's sensor. I'm also inferring that it is a "black and white" camera in so far as it only encodes data from one "colour" channel. In comparison, my modern DSLR camera has a DIGIC 5+ image processor. That image processor was only developed in the last couple of years, but its ADC is only 14 bits per colour channel. A higher number of bits means you have more discrete values that the processor can "sense" from each color channel. Put another way, more bits means more "shades" of a given colour. Note: I realise that most PCs encode colours in combinations of red, green and blue, encoded in three 8 bit fields, so can't display all the nuances of colours aquired using a 14 bit or 16-bit ADC.

Sorry guys. Phil's review pushed me over the edge. I'm just gonna wait for it to show up on Netflix... Which is sad because it had so much potential to be a great movie. I was looking forward to it when I saw the first trailer.

Beauty is in the eye of the beholder. If you ever have to be plucked off a ship or mountain side in a hurry, that helicopter will be a very welcome sight. They really are beautiful for their utility.

I disagree. Landing humans on Mars doesn't change our perspective on where we stand in the universe. Images, captured for the first time ever, showing the immensity of the universe and revealing, in no uncertain terms, our own insignificance in it are far more important to our collective psyche. They should be both humbling and frightening. Remember that it was only AFTER Einstein's General Relativity was published that we discovered that there was a universe filled with galaxies outside what we now call the Milky Way. Many people still regard Einstein's discovery of GR as relatively recent, but the discoveries of extragalactic astronomy are even more recent. The Hubble deep sky images featured in that video reveal that there are even more galaxies outside our own unremarkable galaxy than we had ever imagined. Those photos, together with the Apollo images of the Earth and the various "Pale Blue Dot" images give us a perspective that we have never before had in our history. They open our eyes for the first time.

As dorky as it is, I love the little details in these cartoons. Like the badge on Philae's backpack:

You do realise that Mazon Del and I are joking, right?

Or, you should say, some of his crew aboard the Victoria were the first to "orbit" the Earth. Nao Victoria was the only ship in Magellan's initial fleet of 5 ships to completely circumnavigate the Earth. Magellan himself was killed in a battle in the Philippines during the expedition. Magellan's crew didn't have to fire their thrusters to keep from falling...

Eewww! [10 chars]

Sorry. I assumed that you weren't aware of stacking as you were going on about how "only physically counter-rotating the camera on an equatorial mount" could avoid star trails. But I do agree that a tracking mount is a nice to have. Given that stacking is as effective as it is, I am sure that a combination of a tracking mount and stacking would be awesome! I've got my eye on a tracking mount but I haven't bought it yet because there's no point when you live somewhere where it is almost always cloudy. Maybe I'll spring for one if I go on a trip to somewhere with more reliably clear skies.

You can't "untrail" the stars, but you can avoid capturing star trails in the first place by taking shorter exposures. You can then use image stacking software like the free Deep Sky Stacker to stack multiple images into an image with higher effective exposure length. Use the "Rule of 500" to set an upper limit for your exposure length and then adjust your ISO and aperture as required for the image you're trying to shoot. Fire off a number of shots (light frames), plus some dark frames and bias frames and then load them into DSS. The software will automatically rotate each light frame to correct for the Earth's rotation by aligning the pattern of stars.

Me too. I'll eat anything that won't eat me first. Presumably that includes all vegetables.

Named after the glider or the dwarf?

That's great, but I am talking about the story lines of movies that are advertised as having "great special effects". Gravity had great special effects and "accurate physics" too, but I thought the story sucked. I am not alone. Likewise, there are already plenty of preliminary reviews of Interstellar (some of which are linked to upthread by other members of this forum) that suggest that Interstellar's story sucks too. As I said earlier, I will probably go and see it. I just expect to be disappointed by the story.

Sadly, I have to agree with you. I avoid going to see films that are advertised as "having great special effects" because that is almost always synonymous with "it has a schlocky plot". I have made exceptions to my own rule for movies like Gravity, but I usually end up wishing I hadn't. Gravity was advertised as having great special effects and accurate physics, but the story was nothing more than a continual procession clichés. I don't expect any different from Interstellar (although I will probably go and see it too). I suspect that the reason they got Apollo 13 right was because the real-life events already had all of the necessary elements of a compelling story. They just had to compress that real-life story into a screenplay.

I'm afraid that I've long since outgrown trick-or-treating. Heck, most of my friend's kids have even outgrown trick-or-treating. I'm still enough of a kid at heart, though, that I enjoy Halloween. And I've been known to steal an item or two from the candy stash that my wife and I buy each year to give out to the neighborhood kids. So my question is this: What's are people's favorites? Not sure if they're available elsewhere in the world, but my favorite are "Rockets". No really.

A Google search revealed one preliminary media report so far from the Associated Press: Virgin Galactic reports problem during rocket-powered flight of SpaceShipTwo

Or maybe they've set an example of how to be gentlemanly and, rather than implode under titanic fury, we'll all hold hands and sing kumbaya?

For the record, aircraft do not just generate shock waves (heard on the ground as a sonic boom) while transitioning to supersonic flight. While it is true that you only hear one "boom" (sonic booms from high altitude aircraft actually sound a lot like thunder) as a supersonic aircraft goes by, the guy a few dozen kilometers down the road will hear it too. He'll just hear it a minute or so later than you did as the aircraft passes his location. Much like the bow wave of a boat, the shock travels with the aircraft as it flies along. I have experienced this personally. About a dozen years ago, while sailing a northern route across the Atlantic, we heard the Concorde's sonic boom many times. Sometimes more than once a day. This despite being thousands of kilometers from where the Concorde would transition to/from supersonic flight. You could recognize it as a sonic boom by the clap of thunder coming out of the clear blue sky, followed by the sound of far-off jet engines. And also, as Nibb pointed out, a vapor cone can form while an aircraft is flying below supersonic speeds (TAS). Here's a video of an F18 developing a vapor cone during a high speed pass at an airshow in the US. Notice that there's no sonic boom associated with the pass:

I am not sure that the crew of the sailboat was entirely at fault. Looking at the nautical charts for the Atlantic coast off Wallops Island, the exclusion zone is identified as "Danger Zone 334.130". The US federal regulations pertaining to that exclusion zone include the following requirement: I could not find any announcement of a closure in the weekly Notice to Mariners for US Fifth District (which includes Virginia), either in this week's or last week's publication. I don't know if they were announcing the closure of Danger Zone 334.130 on one of the VTS or weather frequencies (and I have no reason to believe that they weren't), but the exclusion zone extends out to 35 NM from the coast and nobody would be able to see the visual signals from that far out (the reports I've read say that the sailboat may have been as much as 40 NM off the coast). If someone has more information that proves that the guy was "obviously an idiot" then go ahead and post it. In the absence of such information, I don't think it is fair to point the finger of blame entirely at the sailors.

Reading that manifest, it is clear that this launch failure really was a tragedy. Not a human tragedy, but a tragic loss of a lot of valuable scientific experiments and commercial equipment. This will be a huge setback for many many people.