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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.
"550,000 million dollar Kepler space telescope"
I think you're about 3 orders of magnitude too high.
"Who needs NASA?"
wtf kind headline is that?
The actual article is here, on ieee.og
http://spectrum.ieee.org/geek-life/hands-on/diy-exoplanet-detector?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+IeeeSpectrumFullText+%28IEEE+Spectrum+Full+Text%29
The more complete source article
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
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.
a smartphone and an app!
Well ok so some Italian already discovered Jupiter's moons, but if they hadn't, you could!
A very nice use of existing and well known technologies and some clever manufacturing of other parts. "Well done that man!" as my father would say. Of course the naysayers who have't done a fucking thing as nifty as this will be "blah blah blah......".
He's built his own tracking mount, which is nice, but many astrophotographers do this and you can also buy gear that will do it for you. This isn't new in any way. What's different is that he's shown he can detect a star's dimming due to an exoplanet pass using cheap detector gear. That's more impressive. You can see his raw data here.
soylentnews.org
To actually *go* there!
Want a shallow depth of field? Think you need a large lens / fast lens? Why? When the computer can take multiple photos at different focal lengths and calculate the depth properly. Why twiddle with zoom and f-stop?
Because by the time my camera gets around to taking several photos at various focal lengths, the fast moving subject I was trying to take a picture of already left the scene. But I have the opposite problem (since I can fake a shallow depth of field in photoshop) -- I have to open the lens all the way on my P&S in any kind of low-light situation since the sensor is too noisy at high ISO's, so I end up with a shallower depth of field than I wanted.
Want a fast lens? Point and shoots go down to f1.8 now. I can photograph the craters on the moon with a pocket sized G7X without a tripod FFS. How often do you try to detect planets in other solar systems?
I want a fast lens *and* a larger, lower noise sensor than I can find in most P&S cameras. But I don't use that fast lens for taking pictures of planets or the moon.
Want to shoot wildlife at a distance? Think your DSLR is the best option? Think again, you should be using a higher pixel camera at a lower zoom, because you'll have difficulty tracking the moving object at high zoom with that lumping great lens.
Right, all those sports photographers that use the big $8000+ 300mm telephoto lenses could save some money and just get a point a shoot with more pixels than his 20MP DSLR and he can just crop down the pictures to give him a nice 3MP shot of the winning touchdown. Pixels are pixels, right? The 1/2" sensor on a 20MP point-and-shoot is just as good as the 35mm sensor on his DSLR, right? And what possible difference could there be between an $8000 lens and the lens on a $500 P&S?
Want to shoot movies? Do you see any pros using DSLRs? They use a Red or similar, not a Canon EOS.
Here's a list of 30 movies and TV shows that have been shot in whole or part on Canon or Nikon DSLRs:
http://www.imdb.com/list/ls059...
"Honey, I just discovered a planet and I'm going to name it after you. An entire planet."
Table-ized A.I.
If the article is correct it's only useful for checking transit events. The article talks about "a target star". "A star" has a low probability of having a planet in an orbit that gives transit events. Depending on the orbit of the planet it is next to 0 to 10%.
That is why the expensive systems check many stars at once. Kepler monitors 145,000 stars at once
That doesn't mean much. NASA always lacks money to do awesome stuff. So I feel that cost is a good metric here:
Kepler monitors 145,000 stars and costed $600,000,000. That means $4,138 per star
This costs $300 + $100 + some work = +/- $500 per star. If the same software could be used then it might be possible to check more stars with a single DSLR. Maybe even a hundred.
That means $6 per star (naively assuming his setup is sufficient for large scale deployment)
I say: if and when Kepler dies we should stick a couple of them on every observatory we have and have full time monitoring across the planet. False positives drop with more data.
False negatives would still require different detection methods since most exoplanets don't transit. However if we have this set up we might be able to add thousands of spectrometers to it to detect Doppler shift events. Then the only planets with low detection chance are the ones where we look directly on the top (or bottom) of their orbit.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
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
One cannot escape the fact that bigger apperture telescopes can record fainter
stars, and/or perfom the photometry of bright stars with more precision than a simple camera.
To detect exoplanets one needs both large samples of stars recorded as continuously as
possible over several years and high precision photometry. Besides being cheap, the advantage
of a small camera is than the field is larger. But with a larger telescope in space like Kepler one
can target regions of the sky with density of stars optimal for the CCD/camera combination, and
observe continuously for months with the same instruments, which is crucial for differential
photometry. Thousands of amateurs worldwide detecting as many new exoplantes as Kepler
would face the problem of coordinating the analysis of huge amounts of heterogeneous and
incomplete data (due to day/night and weather interruptions in differently dark and transparent skies).
The real question is wether crowdsourcing planet detection is cheaper for global economy at equal scientific return than with state sponsored research. Perhaps the most important benefit of such an
activity is educational and promotional for research in general.
This is a nice excercise in performing wide-field astrophotography and photometry with simple equipment but...
The article does not provide a lightcurve.
He already knew where and when to look so he accounts any magnitude variations to the presence of an exoplanet. In reality, can he tell the difference between variable stars and stars with exoplanets by only looking at his data?
Also it is sad that the article describes 99% his camera setup and 1% (or less) his data processing workflow.
I cannot commend this post enough. OC was completely and totally off-base.
Americans...
Wow... You are wrong on almost every count in this post. Impressive.
Only to find out later that it's just a speck of dust on the CCD.
Many amateurs have already contributed to the effort. Variable Star Observers(VSO) have been collecting information for a very long time. This information has been useful for much more than just the search for exoplanets. Taking part in VSO efforts is one of the few ways that private individuals in their spare time can make real contributions to data used by current day scientists.
Seriously, a DSLR sensor is 35mm because the film it replaced is 35mm.
Mostly wrong. Only high-end professional-oriented DSLRs have 35mm-sized sensors, the majority use smaller APS-C sized sensors or something in that ballpark.
"Slashdot - News and Chat Sites Deviant". (Click "homepage" link above for details).
> Also it is sad that the article describes 99% his camera setup and 1% (or less) his data processing workflow.
Well it was on a photography site, not an astrophysics or computing site....
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.
"Because by the time my camera gets around to taking several photos at various focal lengths, the fast moving subject I was trying to take a picture of already left the scene."
No, its far faster than you can turn the focus ring to get the depth right. Your fingers won't even reach the lens ring in that time.
"I want a fast lens *and* a larger, lower noise sensor than I can find in most P&S cameras"
You cannot take shots faster than the shutter or need shots of fainter objects than stars. So the overspec on your DSLR is actually doing three things. It makes the camera ridiculously big, it is limiting the focal zoom possible because of the lens size, and the size is electrically slow meaning it is outperformed by smaller cameras.
Your DSLR is genuinely crap compared to the modern 4/3rds and a damn site less portable than the best point and shoots.
"Right, all those sports photographers that use the big $8000+ 300mm telephoto lenses"
And yet they're moving to Micro 4/3rds now, because it smaller, the big zoom lens are more practical. In the meantime, since 2008, when M4/3 came out, the sensors have gotten far better, and the cameras can be smaller, so the lens can zoom more, the electrical performance of the sensor can be a lot faster. You don't need to live with the poor zoom level of a DSLR, the ridiculous weight of the lenses, the piss poor video performance.
Ditch the DSLR, its a terrible jack of all trades camera. Now that the sensors have moved on, so must the camera.
When DIY'ers start sending rovers to Mars and probes to Pluto, then we can ditch NASA...
A DSLR has managed to detect a large planet in a fast orbit around a small, close star. Kepler is sensitive enough to detect earth-sized planets orbiting G-type stars at 1AU, A DSLR (or even conventional telescope) can't replicate that.
I suspect most (all?) of the transiting planets that today's DSLRs could detect have probably already been detected by sky surveys anyway.
Technology keeps getting better, we don't need space anymore!
Come on, really? In a story about exoplanets you can't even spell exoplanet??
Lost at C:>. Found at C.
Even APS-C is overkill, try the current crop of 1 inchers.
No, its far faster than you can turn the focus ring to get the depth right. Your fingers won't even reach the lens ring in that time.
Uh, just because it is faster than your manual focusing doesn't mean it is faster than your subject.
Slashdot Deal in the future.
The gp displays the standard ignorance of a novice photographer, who doesn't even know that he knows nothing about photography because his hardware allows him to take pictures he deems "good". There's a reason there are professional photographers out there that get paid well and use "pro" equipment, but until gp tries to take pictures outside the limited scope of a P&S, he won't realize how limited he is. Should he use a pro-sumer or better grade camera, he may be disappointed in his pictures not being "better" than the P&S, that's not a fault of the equipment but more his failure to understand how to use that equipment to get great pictures. And even then, great pictures don't just happen automatically, it is luck or many tries, and sometimes significant post-processing before a great picture is realized. To be fair, sometimes that is also achievable with a P&S.
The cesspool just got a check and balance.
Erm how so? GP argued that the shutter taking multiple shots to get a shallow depth of field would be too slow (its milliseconds on these cameras now), yet he has his DSLR out, the lens on and is ready to get a shallow depth of field effect, and he still has to set his camera manually to get his depth of field right for his moving subject and somehow thats faster (!).
(As to the shallow depth of field, taking multiple shots and computing the depth is not the crap blur you do with PS or LR !)
His converse argument (that a P&S is noisy in low light so he needs to put up with shallower depth of field than he wants), well he needs to try a 1incher. Really a lot of this could be settled by going to a camera shop, getting one of the top of the range p&s (1 inch and up are the current sweet spot) and living with it.
I've gone from DSLR Nikon F mount system, to Micro 4/3rds mounts, to a fixed lens g1x then g7x, and I might even go to the RX100 to shave off a few mms of size.
I have to say I was a bit shocked when I took the g7x pointed it at the moon, zoomed into full (x17) took a photo, then pulled it into PS and saw it took photographed craters. Hand held! Full zoom! Low light. Craters! FFS, it fits in my pocket.
The manner in which you speak of "zoom" and added in cell phones cameras suggests to me you know nothing about serious photography. All of what you have said is true for consumer snapshots. For serious photography, it is nonsense spewed by someone who knows just enough to be dangerous and not enough to be useful in terms of giving advice to consumers.
Jesus would frown upon your racism.
comets, asteriods and novas. We could have a very large group of people with each small group responible for a small section of ths sky.
15x zoom is bad. Quoting it as 35mm equivalence might make it sound better, but the substance doesn't change.
The fps limits on DSLRs are also bad.
Erm how so?
"baz is faster than bar" does not imply "baz is faster than foo" when when foo is also much faster than bar, that is just basic math...
and he still has to set his camera manually to get his depth of field right for his moving subject and somehow thats faster (!).
Yes, it is faster in the sense you setup the camera before hand, which applies to large number of situations. It sounds more like you have very little actual photography experience, or you use it in such a limited fashion you have no idea what other people actually take photos of.
Yeah, new point and shoots look great when you compare them to older larger sensors... or you could take advantage of the same advances in tech and use it with the advantages of a large sensor too. If price or convenience are your top priority, sure, you can get a lot out of smaller cameras. But not every person has the same priorities and needs.
That question was asked by Bruce L. Gary and the answer is what he wrote in his free book: EXOPLANET OBSERVING
FOR AMATEURS
Not to mention hand-holding a crazy zoom on a high resolution sensor would be nigh impossible without either a tripod or super-nova light levels allowing insane shutter speeds. :|
Smaller sensors also equate to higher noise levels, thus are they limited to working in lower ISO levels than the larger sensors. Fast lenses ( f2.8 and below ) only go so far. You'll need low noise high ISO capability for any less than optimal light stuff you plan on doing. ( Read that, just about anything outside of a studio )
While the point and shoots -can- shoot at higher ISO's, this is where the larger format sensors start to shine. While not all systems are equal, I can pretty much guarantee the P&S isn't even playing the same game when comparing a high ISO shot against a pro-dslr. Not even close. ( ISO 3200 and even 6400 on a Nikon D4s is pretty damned impressive noise wise )
Are DSLR's the best ? Of course not. They're big, they're heavy, expensive and a pain in the ass to carry around. If you're shooting with the big super-teles ( say 500mm and above ) then you'll need a motorcade just to haul all the gear around to support it.
They are, however, still superior to the P&S systems when it comes down to quality of the final image. Which, in the end, is really what matters.
The moon does not qualify as low light beause it is directly illuminated by the sun.
Simply speaking it is as bright as any outdoor scene under broad day-light.
The gp displays the standard ignorance of a novice photographer, who doesn't even know that he knows nothing about photography because his hardware allows him to take pictures he deems "good". There's a reason there are professional photographers out there that get paid well and use "pro" equipment, but until gp tries to take pictures outside the limited scope of a P&S, he won't realize how limited he is. Should he use a pro-sumer or better grade camera, he may be disappointed in his pictures not being "better" than the P&S, that's not a fault of the equipment but more his failure to understand how to use that equipment to get great pictures. And even then, great pictures don't just happen automatically, it is luck or many tries, and sometimes significant post-processing before a great picture is realized. To be fair, sometimes that is also achievable with a P&S.
Truth to this but lighting is the magic ingredient. PS skills especially well done work frequency sep and subtle accurate changes only go so far if it is poorly lit. I don't just mean artificially lit stuff but same goes for available light although admittedly I tend to use monoblocks in portraiture. Not a quality thing more for the control I have over all light sources and "on tap" perfect light any time of day.
Truth to this but lighting is the magic ingredient.
Yes, lighting is key, but even with good or excellent lighting you are not guaranteed a great shot.
The cesspool just got a check and balance.