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Who Needs NASA? Exoplanet Detected Using a DSLR
Iddo Genuth writes Until 20 years ago even the best telescopes in the world could not detect a planet outside our solar system. Now, with the aid of a basic DSLR, low cost lens and some DIY magic, you just might be able to "see" ET's home planet for yourself. Your DSLR can do much more than just take a few nice portraits or the occasional vacation photos – if you have some DIY experience (O.K. a bit more than just "some"), you might be able to repeat what David Schneider was recently been able to do — that is, building his own planet finder using only inexpensive photo gear, low cost electronics, the right kind of software and a lot of patience. Although Schneider was "only" able to rediscover an already known exsoplanet (some 63 light-years away from us), what he did — and more importantly how he did it — might allow planet hunting to become closer to SETI@home than NASA's 550,000 million dollar Kepler space telescope project.
This is a really cool project, with a terrible headline. Without NASA (or perhaps the ESA, or whatever space organization first found this exoplanet), David Schneider wouldn't have been able to look up the timing for the planet's transit. He wouldn't even have know to try taking pictures of that particular star. He'd have to take a lot more photos over a much longer time, over a much bigger area of the sky, and run a lot more image comparision software for a lot longer, before he's have found that transit.
I really want to think that this was a great feat of hardware hacking, but the title of the summary is terrible. The capabilities of space telescopes are designed to overcome the obstacles which plague our earth-bound ones.
Saying that this is a viable replacement for the data coming from a source with lesser disturbances is just undermining the work of a lot of people.
I must admit in skeptical. It is very easy to "see" something that you know is there in data, eliminating runs that you "know" are wrong, etc. Until this is reproduced by someone with similar equipment I will put this down to a fluke
Even with Slashdot's slightly hyperbolic headline, the summary correctly reports the planet as having been "detected" rather then "discovered", and clarifies that this was "only" an already-discovered exoplanet (as does the original article).
If that was your implied criticism, then, it's not valid.
If you understood this, but your point was that "detecting" an already-known exo-planet was pointless because it's alredy been done... even though the person involved did it with equipment orders of magnitude cheaper and lower-end than that originally used by NASA less than a decade back, and which few of us would have assumed possible, which *is* the point here... then Slashdot probably isn't the place for you.
"Slashdot - News and Chat Sites Deviant". (Click "homepage" link above for details).
One reply has already gutted most of your points, so I'll work on the ones he didn't address:
Seriously, a DSLR sensor is 35mm because the film it replaced is 35mm. It's not an engineering choice, it was done so that owners of expensive lenses could use them on the new digital cameras.
Except that not all DSLRs are 35mm, in fact most of them weren't, and most of them still aren't. They were APS-C sized. Or in the case of 4/3rds they were even smaller and not even the same aspect ratio. Yet all the lenses magically still worked.
35mm has enough engineering decisions behind it,
Its not sized large enough to take in a normal range of light, and yet small enough to keep the lens size down so big zoom lenses are possible. It's sized for historic reasons, making it too big and thus limited.
And yet there's no definition for normal range of light and it seems every year there are changes to sensitivity. Are you saying that it was initially not large enough? What about now when cameras go to ISO25600 and beyond?
Lots of things are better done by digital calculation than lenses.
False. Leaving aside the technicalities of deconvolving and correcting for aberrations at different zooms and focus point, there's a much more fundamental saying: "Shit in. Shit out." Every correction make negatively affects an image that could have been right to begin with given how well lenses are understood.
How often do you try to detect planets in other solar systems?
Are you asking how often a man does his hobby? Who are you to question?
Want multiple lenses for those oddball occasions, go with Micro 4/3 like a lot of pros are doing now.
Why, and Who? Seriously I love my EM1 as much as the next person, but you'd be hard pressed to actually point out a pro using micro-4/3rds for anything other than an Olympus promotional video. As for oddball lenses, I think you'll find both the EF mount and the F mount will have a far wider and more oddball selection than anything 4/3ds.
As sensors have gotten better, and lower noise, the sensor in the DSLR has not shrunk in size because of the lens.
No. Quite the opposite. The sensor size has increased. The coupled larger format with the newer sensor technology now makes it possible to take photos that were previously impossible without fancy lighting and careful setups. Upping the sensitivity is no excuse for making things smaller when the benefits can be had across the board, especially since small sensors struggle to get depth of field down.
Big zoom lens are unworkable in DSLR because of the size of the sensors, they would simply be too long.
And yet they have been built and are in active use.
Likewise the size of the sensor is a big problem itself, its slow electrically.
And yet they are used in fast paced sporting situations and 60fps HD video.
So you end up with a camera with worse performance in normal situations, and designed for non-real world situations.
So a camera designed not to take pictures? I'm not sure I follow here.
Trying to find planets literally is what these camera are useful for!
No trying to find planets are what carefully calibrated and cooled CCDs are useful for. Before someone can use a DSLR for anything as technical as this they need to move heaven and earth to properly quantify how their system reacts as sensors used for photography are inherently non-linear trading off accuracy for other aspects. I know someone who uses his Canon DSLR for gauging the variability of stars. He literally recorded months of data before he had something useful enough that he could calibrate his camera for use on a single target.
The fact this works at all is amazing and a testament to the people involved, and definitely nothing to do with technology.