The worlds largest single dish telescope is still the Green Bank Telescope (http://en.wikipedia.org/wiki/Green_Bank_Telescope), which at 100m is ~6x the size.
I went looking for the largest diameter multi-dish radio telescope. It looks like the biggest terrestrial 'telescope' is the Global VLBI system created by combining the European VLBI Network with the US Very Long Baseline Array - it's like some massive team of superheroes combining to save the Earth from some terrible secret of space. Or whatever. Apparently they can also add space-based telescopes when that just isn't enough. Which, quite frankly, is showing off...
My thoughts when seeing one of the beautiful, 10m diameter Keck optical telescopes up close a few years ago? I've had full control of a telescope bigger than that.
I dunno, I always get a big belly laugh whenever I log into something and see that horrible 1980s B&W X11 desktop, complete with ugly 'X' cursor.
Try flying on a Virgin America plane with the LCD screen inflight entertainment systems in the seat-backs. They'll often mass-reboot the things before or after a flight, briefly revealing that retro-fantastic, monochrome stippled background with 'X' cursor...
Do we have any Mars rovers close enough to the poles to not get sunlight in winter?
The non-roving Phoenix Mars probe landed sufficiently far north that reduced sunlight due to an approaching winter caused its (expected) failure. It most likely got buried by carbon dioxide ice later on anyway - orbital photos showed its solar panels got crushed...
For keeping space probes warm, radioisotope heater units are pretty common. Apparently the Chinese Moon rover has them - but it sounds like it hasn't successfully closed itself up in order to keep heat inside.
The Babbage difference engine model is in the Computing section, on the 2nd floor
Definitely still there when I visited in early December last year - loads of Babbage stuff, in fact. Including his brain in a jar!
(The museum did feel kind of tired and empty compared with how I remembered it, sadly - and the Wellcome collection stuff didn't seem nearly as grisly as I thought it was as a ten-year-old. They've got some fancy new galleries at one end, but it's more of the raising-questions public-oriented kind of display rather than the dusty old real exhibits I've really come to appreciate. I did get a bit spoiled by the two branches of the Museum of Flight in Washington DC about a year ago, however. Blimey. Spaaaaaace!)
I always liked the working electromechanical telephone exchange.
If you're ever in Seattle, try the Museum of Communications. Fairly large old telephone exchange with colossal amounts of powered-up electromechanical telephone equipment - place a call on a phone and hear it rattling through the machinery until another phone next to you starts to ring. Loads of old teletypes, UNIX boxes and miscellaneous other hardware to look (and often poke) at.
Basically nerd heaven, yet surprisingly few people round here have heard of it. Makes the equivalent display at the London Science Museum look a bit silly.
I checked out that link and it looked like I was stepping back into the 90s. That image on the home page looks like it's a 256 colour GIF! Where's the specular mapping? Everything in those shots looks dead, like a bad phong highlighted raytrace.
There's much more impressive stuff going on with path tracing on conventional GPUs - something that, at least for me, is making a definite case for ungodly improvements in processing power for GPU hardware.
I've got a very-first-generation, USB-hobbled-by-polyfuses-until-I-performed-surgery-on-the-thing 256MB Raspberry Pi. The thing's part of my time-travelling Radio-4-Matic and thus transfers a few gigabytes a day over a little USB WiFi adaptor by streaming radio over the intertubes, buffering it for some hours then playing it back.
Uptime? Right now: 19:12:14 up 52 days, 15:46, 1 user, load average: 0.01, 0.09, 0.12
Last reboot was for a system upgrade of some description; the things are pretty stable now. (There have been many improvements to the firmware and system software.) My other Pi (a more recent 512MB model) is busy being a tiny home fileserver and virtual server backup device (remote stuff rsyncs over ssh to this thing) - I could easily use a spare PC for those tasks, but the result would be a lot less near-silent and much more power-hungry. Plus it can saturate 100Mbit ethernet with file serving - faster isn't much use when most of my stuff is on WiFi.
Make sure you've got a decent power supply. Apparently voltage drops can be a big source of instabilities. Power for my midget fileserver is via a Samsung cube phone charger; the radio's got a hacked-together DC-DC converter running off a mains-to-12V-DC adaptor. (I'm surprised the thing is as stable as it is, what with it solely relying on my impromptu electronics hackery!)
But in the end, it's all nothing but quarks and electrons, bound together and moving in various combinations and patterns, interacting via strong force (gluons) and electromagnetic force (photons).
I'm using Mail.app with Dovecot as the IMAP server - I upgraded to OS X 10.9 a few days ago, and haven't seen anything weird going on (yet). I sent myself a test email a few minutes ago while watching the Mail Activity window, and numbers appeared sensible. dovecot.index and dovecot.index.cache files on the server aren't ballooning - at 178KB and 11MB respectively.
The Fastmail article mentions Cyrus as the IMAP server. Is it Cyrus-specific, or have I simply not been bitten by this yet? (I get loads of spam, but it gets pre-processed by Spamassassin so Mail.app rarely gets to see any in the main inbox itself.)
An entire PCB filled with parts? This looks like an example of someone too smart for their own good.
The photo seems to be of this thing, which is an entirely different device which apparently 'allows a computer (or "host") to masquerade as a USB "device" to communicate with other USB devices or USB Hosts.'
In other words, exactly the kind of device you wouldn't want to unknowingly connect things to.
A couple of years ago I modified my old EOS 350D, replacing the IR-blocking hot mirror in front of the sensor with a filter that only allows IR through. I've taken loads of photos with it since then (please excuse the increasingly crap Flickr) - pretty much all hand-held with available light. Depending on the conditions (metering still works on visible light) I might be +1 or +2 stops up on typical outdoors scenes, while -1 or -2 stops down on near-IR-bright scenes like under forest canopies.
Images are generally pretty much direct from camera, all using the same white balance (set off a piece of white paper under tungsten light when I first did the conversion) - blue tones vaguely correspond with longer wavelengths. In-camera contrast is whacked up to the maximum, but little else. (The custom white balance is kind of weird - with a 'normal' setting, pictures come out looking fluorescent pink.)
I haven't noticed any magical see-through-clothes abilities from the camera, although I haven't really checked...
$42, but free shipping so I'll let that slide - no ethernet or GPIO, but does have built-in WiFi and 8GB flash storage and includes a mains adaptor. Will run Linux (with hardware-accelerated OpenGL ES) via the unfortunately-named Picuntu.
If someone finds me a similarly-sized Raspberry Pi alternative for $35 (plus reasonable postage and packing) that has a semi-decent GPU, USB, ethernet, audio and GPIO, and runs Linux - I will buy it and report back.
(The BeagleBone Black looks interesting at $45. I think I might get one of those anyway...)
(Full documentation here. It's a 1970s transistor radio with WiFi, streaming Radio 4 over a SSH tunnel to the UK, time-delaying audio playback by eight hours or so, in order that everything gets played back at the correct local time in Seattle.)
I don't know what you mean by "old", but my father's old Canon (film) SLR's EF-mount lenses pop right onto my relatively new Canon EOS Rebel T2i (EOS 550D for you non-Americans) which takes EF-S-mount lenses.
EF-S is a subset of the redesigned-from-scratch EF lens mount from 1987 - still considered terribly modern 'cause it's fully electronic with no mechanical linkages between the camera and lens. New EF lenses are definitely still being designed, but yes - EF-S lenses won't fit on an EF-only camera, be it film or full-frame digital.
Canon's 'old' system is the FD lens mount, from 1971. The newer EF mount is almost completely incompatible - you'd need that overly-complicated-adaptor-with-included-optical-elements to get an FD lens to mount on an EF camera.
Compare Nikon's F-mount - lenses from 1959 are potentially mechanically compatible with the latest Nikon dSLRs, but there are huge compatibility charts describing which features may or may not work from any particular lens on any particular camera.
I have other CanonDSLRs that do the "video thing" out of the box, but it sounds. like an interesting experiment.
The particularly exciting thing about this hack is that it's not just a previous non-video-capable camera recording video, it's a camera recording 14-bits-per-channel linear uncompressed RAW video. Much better highlight and shadow recovery, white balance defined afterwards, much more information to work with in general. Some really tricky shots are now possible.
It does not have enough RAM to buffer frames continuously at uncompressed DNG format rates for continuous video recording to SD card, whereas other cameras that were designed specifically for video recording have enough memory to be capable of doing this.
The buffer is important, but it's more about being able to stream a metric shitload of data to a unwholesomely speedy memory card - once you can do the latter, the buffer helps smooth over hiccups but won't let you record indefinitely. The 50D's CompactFlash interface probably shares a design with a higher-end camera, Canon not wanting to waste effort in building a second, deliberately crippled version.
Thus my interpretation is that this camera model's hardware specs were deemed insufficient by the manufacturer for this specific capability, and considering that it can only do burst mode up to $X$ frames before capping out its memory buffer, the manufacturer may have been correct.
Being able to record RAW video is a pretty new feature on any vaguely consumer-oriented camera - it's more sheer luck that Canon's dSLRs have features which make it possible, albeit in a hacky manner. I get the impression that on the 50D, it's grabbing data from the sensor in a manner intended for the rear display or for feeding into the (non-existent) H.264 encoder, and then streaming it out to a big file on the memory card before the memory runs out.
When you've captured the data, it's in a big, opaque file that needs post-processing on a PC to do anything with it - in this case, it gets split into sane DNG files for further processing in software like Lightroom or similar. You can record the video on the camera, but you can't (unless I'm horribly mistaken) play the video on the camera - you need to do plenty of subsequent processing to get it into video form.
Don't get me wrong, it's an incredibly cool hack - partly because it gives access to a feature which few high-end cameras have even today. It's not the manufacturer deliberately locking users out of an easily-implemented feature, it's the manufacturer not even realising that such a feature was possible - albeit in a restricted, but still usable, form.
Slashdot Mirror
+1, Interesting.
(Thanks!)
Oops. That was in reference to his Green Bank Telescope link - Arecibo being only partially steerable...
The Extremely Large Telescope is a compromise - what they really wanted was the 100m-diameter Overwhelmingly Large Telescope.
Their naming committees are either entirely humourless or gloriously taking the piss.
World's largest fully-steerable single-dish telescope - the Arecibo Observatory is larger still at a diameter of 300m! (Impressive Arecibo exploration video here. The thing's sodding enormous.)
I went looking for the largest diameter multi-dish radio telescope. It looks like the biggest terrestrial 'telescope' is the Global VLBI system created by combining the European VLBI Network with the US Very Long Baseline Array - it's like some massive team of superheroes combining to save the Earth from some terrible secret of space. Or whatever. Apparently they can also add space-based telescopes when that just isn't enough. Which, quite frankly, is showing off...
My thoughts when seeing one of the beautiful, 10m diameter Keck optical telescopes up close a few years ago? I've had full control of a telescope bigger than that.
Radio Astronomers: Compensating For Something.
Piwik is a self-hosted web analytics package. In other words, your visit to an EFF page is being tracked by the EFF.
Try flying on a Virgin America plane with the LCD screen inflight entertainment systems in the seat-backs. They'll often mass-reboot the things before or after a flight, briefly revealing that retro-fantastic, monochrome stippled background with 'X' cursor...
The non-roving Phoenix Mars probe landed sufficiently far north that reduced sunlight due to an approaching winter caused its (expected) failure. It most likely got buried by carbon dioxide ice later on anyway - orbital photos showed its solar panels got crushed...
For keeping space probes warm, radioisotope heater units are pretty common. Apparently the Chinese Moon rover has them - but it sounds like it hasn't successfully closed itself up in order to keep heat inside.
It's entering its second lunar night - it landed on the Moon on December 14th.
No idea, but probes from other places have a peculiar tendency to write about themselves too.
Definitely still there when I visited in early December last year - loads of Babbage stuff, in fact. Including his brain in a jar!
(The museum did feel kind of tired and empty compared with how I remembered it, sadly - and the Wellcome collection stuff didn't seem nearly as grisly as I thought it was as a ten-year-old. They've got some fancy new galleries at one end, but it's more of the raising-questions public-oriented kind of display rather than the dusty old real exhibits I've really come to appreciate. I did get a bit spoiled by the two branches of the Museum of Flight in Washington DC about a year ago, however. Blimey. Spaaaaaace!)
If you're ever in Seattle, try the Museum of Communications. Fairly large old telephone exchange with colossal amounts of powered-up electromechanical telephone equipment - place a call on a phone and hear it rattling through the machinery until another phone next to you starts to ring. Loads of old teletypes, UNIX boxes and miscellaneous other hardware to look (and often poke) at.
Basically nerd heaven, yet surprisingly few people round here have heard of it. Makes the equivalent display at the London Science Museum look a bit silly.
Also, if you arrived at a hospital saying you were there for an NMR, you might have received something other than what you were expecting.
There's much more impressive stuff going on with path tracing on conventional GPUs - something that, at least for me, is making a definite case for ungodly improvements in processing power for GPU hardware.
I've got a very-first-generation, USB-hobbled-by-polyfuses-until-I-performed-surgery-on-the-thing 256MB Raspberry Pi. The thing's part of my time-travelling Radio-4-Matic and thus transfers a few gigabytes a day over a little USB WiFi adaptor by streaming radio over the intertubes, buffering it for some hours then playing it back.
Uptime? Right now:
19:12:14 up 52 days, 15:46, 1 user, load average: 0.01, 0.09, 0.12
Last reboot was for a system upgrade of some description; the things are pretty stable now. (There have been many improvements to the firmware and system software.) My other Pi (a more recent 512MB model) is busy being a tiny home fileserver and virtual server backup device (remote stuff rsyncs over ssh to this thing) - I could easily use a spare PC for those tasks, but the result would be a lot less near-silent and much more power-hungry. Plus it can saturate 100Mbit ethernet with file serving - faster isn't much use when most of my stuff is on WiFi.
Make sure you've got a decent power supply. Apparently voltage drops can be a big source of instabilities. Power for my midget fileserver is via a Samsung cube phone charger; the radio's got a hacked-together DC-DC converter running off a mains-to-12V-DC adaptor. (I'm surprised the thing is as stable as it is, what with it solely relying on my impromptu electronics hackery!)
Actually, below that it's mostly Perl.
I'm using Mail.app with Dovecot as the IMAP server - I upgraded to OS X 10.9 a few days ago, and haven't seen anything weird going on (yet). I sent myself a test email a few minutes ago while watching the Mail Activity window, and numbers appeared sensible. dovecot.index and dovecot.index.cache files on the server aren't ballooning - at 178KB and 11MB respectively.
The Fastmail article mentions Cyrus as the IMAP server. Is it Cyrus-specific, or have I simply not been bitten by this yet? (I get loads of spam, but it gets pre-processed by Spamassassin so Mail.app rarely gets to see any in the main inbox itself.)
Actually, one of them makes pretty hefty donations to science-related stuff, including big exhibits at the American Museum of Natural History. Human evolution, and all that.
(The socialist in me wonders if the latter is revealing some belief in social darwinism - survival of the fittest, and all that. Eek.)
The photo seems to be of this thing, which is an entirely different device which apparently 'allows a computer (or "host") to masquerade as a USB "device" to communicate with other USB devices or USB Hosts.'
In other words, exactly the kind of device you wouldn't want to unknowingly connect things to.
A couple of years ago I modified my old EOS 350D, replacing the IR-blocking hot mirror in front of the sensor with a filter that only allows IR through. I've taken loads of photos with it since then (please excuse the increasingly crap Flickr) - pretty much all hand-held with available light. Depending on the conditions (metering still works on visible light) I might be +1 or +2 stops up on typical outdoors scenes, while -1 or -2 stops down on near-IR-bright scenes like under forest canopies.
Images are generally pretty much direct from camera, all using the same white balance (set off a piece of white paper under tungsten light when I first did the conversion) - blue tones vaguely correspond with longer wavelengths. In-camera contrast is whacked up to the maximum, but little else. (The custom white balance is kind of weird - with a 'normal' setting, pictures come out looking fluorescent pink.)
I haven't noticed any magical see-through-clothes abilities from the camera, although I haven't really checked...
$42, but free shipping so I'll let that slide - no ethernet or GPIO, but does have built-in WiFi and 8GB flash storage and includes a mains adaptor. Will run Linux (with hardware-accelerated OpenGL ES) via the unfortunately-named Picuntu.
Interesting. Anyone got anything better?
If someone finds me a similarly-sized Raspberry Pi alternative for $35 (plus reasonable postage and packing) that has a semi-decent GPU, USB, ethernet, audio and GPIO, and runs Linux - I will buy it and report back.
(The BeagleBone Black looks interesting at $45. I think I might get one of those anyway...)
I put my Raspberry Pi in a box and it appeared on national radio. :-(
(Full documentation here. It's a 1970s transistor radio with WiFi, streaming Radio 4 over a SSH tunnel to the UK, time-delaying audio playback by eight hours or so, in order that everything gets played back at the correct local time in Seattle.)
EF-S is a subset of the redesigned-from-scratch EF lens mount from 1987 - still considered terribly modern 'cause it's fully electronic with no mechanical linkages between the camera and lens. New EF lenses are definitely still being designed, but yes - EF-S lenses won't fit on an EF-only camera, be it film or full-frame digital.
Canon's 'old' system is the FD lens mount, from 1971. The newer EF mount is almost completely incompatible - you'd need that overly-complicated-adaptor-with-included-optical-elements to get an FD lens to mount on an EF camera.
Compare Nikon's F-mount - lenses from 1959 are potentially mechanically compatible with the latest Nikon dSLRs, but there are huge compatibility charts describing which features may or may not work from any particular lens on any particular camera.
The particularly exciting thing about this hack is that it's not just a previous non-video-capable camera recording video, it's a camera recording 14-bits-per-channel linear uncompressed RAW video. Much better highlight and shadow recovery, white balance defined afterwards, much more information to work with in general. Some really tricky shots are now possible.
The buffer is important, but it's more about being able to stream a metric shitload of data to a unwholesomely speedy memory card - once you can do the latter, the buffer helps smooth over hiccups but won't let you record indefinitely. The 50D's CompactFlash interface probably shares a design with a higher-end camera, Canon not wanting to waste effort in building a second, deliberately crippled version.
Being able to record RAW video is a pretty new feature on any vaguely consumer-oriented camera - it's more sheer luck that Canon's dSLRs have features which make it possible, albeit in a hacky manner. I get the impression that on the 50D, it's grabbing data from the sensor in a manner intended for the rear display or for feeding into the (non-existent) H.264 encoder, and then streaming it out to a big file on the memory card before the memory runs out.
When you've captured the data, it's in a big, opaque file that needs post-processing on a PC to do anything with it - in this case, it gets split into sane DNG files for further processing in software like Lightroom or similar. You can record the video on the camera, but you can't (unless I'm horribly mistaken) play the video on the camera - you need to do plenty of subsequent processing to get it into video form.
Don't get me wrong, it's an incredibly cool hack - partly because it gives access to a feature which few high-end cameras have even today. It's not the manufacturer deliberately locking users out of an easily-implemented feature, it's the manufacturer not even realising that such a feature was possible - albeit in a restricted, but still usable, form.