[HN Gopher] Milky Way, 12 years, 1250 hours of exposures and 125...
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Milky Way, 12 years, 1250 hours of exposures and 125 x 22 degrees
of sky
Author : giuliomagnifico
Score : 485 points
Date : 2021-03-17 13:07 UTC (9 hours ago)
(HTM) web link (astroanarchy.blogspot.com)
(TXT) w3m dump (astroanarchy.blogspot.com)
| thanatos519 wrote:
| What do I have to do to get the full-size image? The 7000x1300
| pixel image is pretty nice, but I was thinking of making a
| 1440dpi print on 4 sheets of A3+.
| epaga wrote:
| Looks like you'll need to email him directly.
| https://astroanarchy.zenfolio.com
| ACAVJW4H wrote:
| I had the urge to print as well. I doubt he'll be interested in
| giving away this masterpiece, atleast for an affordable price.
| I'll mail and ask; he might offer a print service maybe.
| [deleted]
| eutropia wrote:
| This got me thinking about treating a surface with Black 3.0
| paint and printing astrophotography images on top of that, but I
| wouldn't know how to get a large format printer to safely print
| on top of the treated material.
| ACAVJW4H wrote:
| > My observatory is located in the very center of the city Oulu
| in Finland. Due to massive Light Pollution I mainly do ...
|
| Well I guess most of us live in filthy cesspools of light.
| Seriously I wonder what humanity misses out on. I think we would
| have been a much better species if only we could see our place in
| the universe every night.
| hedshodd wrote:
| There was this one time where in some city in the US, cannot
| remember which, there was a city wide power outage, and some
| people were freaking out because they've never seen a non-
| polluted sky before.
| MattRix wrote:
| Would have been a much better species? Bright lights are a very
| recent part of our species' history. It's not like humanity had
| a reputation for being particularly civilized before the
| invention of electric light.
| AnIdiotOnTheNet wrote:
| Depends on what you mean by "civilized", but I take your
| point. I do wonder, however, if there isn't a correlation
| between the increase of light pollution and the trend away
| from reverence for gods. In other words, does the ability to
| see the grandeur of the heavens on a daily basis influence us
| to believe in greater beings?
| marc_io wrote:
| On a side note: there is a great documentary on light
| pollution called "Saving the Dark" (it's on Youtube). This
| really has a big impact on us and the environment.
| mym1990 wrote:
| I do some astrophotography from time to time and it has been a
| great way to get away from it all to get some perspective while
| stargazing.
|
| On occasion I venture out into dark sky areas in the US with
| friends, and they are always surprised that it is possible to
| see the milky way with the naked eye(or just so many stars at
| all).
| doubtfuluser wrote:
| Over that long period of time, isn't there the effect of star
| movement at least a tiny bit visible?
| [deleted]
| notjes wrote:
| 12 years might be too short of a time frame for objects that
| are moving about 1/1000 of the speed of light. It would be
| interesting to see a comparison of 50 or 100 years. The center
| should be rotating faster or slower?
| shireboy wrote:
| This is stunning - both the image itself and the 12 years of
| dedication making it. Well done.
| neolog wrote:
| > Image in mapped colors from the light emitted by an ionized
| elements, hydrogen = green, sulfur = red and oxygen = blue.
|
| Is there a relationship between those colors and those elements,
| or just an arbitrary mapping?
| nxpnsv wrote:
| Beautiful, and respect! Seems many photographers collaborating
| could achieve similarly amazing results a lot faster, is that a
| thing and if so can I join?
| platz wrote:
| It looks a little grainy / too much sharpening to my eye. Natural
| images tend have more blended features instead of looking like
| sand.
| realo wrote:
| When someone shows you the moon, do you start talking about her
| finger?
|
| Peace!
| platz wrote:
| I definitely would
| EForEndeavour wrote:
| I can kind of see what you mean, but I wonder if this is
| actually a result of the subject, not processing. The night sky
| is absolutely peppered with pinpoints of light far smaller than
| individual image pixels (resolvable stars) which are quite
| unlike typical terrestrial scenes.
| platz wrote:
| The effect seems to be more noticeable in the areas filled
| with gas.
|
| I'm not saying that stars aren't pinpoints or sometimes are
| just single pixles, but just it overall looks like some post-
| sharpening has definitely been applied aggressively to my
| eye.
| foo_barrio wrote:
| Looking at this pic of the Orion nebula it looks like even
| the smoothest, darkest areas have tons of stars in them: *
| https://orion2020v5b.spaceforeverybody.com/
|
| This is also a much smaller area of the sky. The higher
| acuity of the image might actually be more representative
| of what the telescope actually sees. The smooth darkness
| you are used to seeing might be similar to how some people
| prefer music where the treble rolls off (like tube amps or
| sennheizer 650s headphones) vs people preferring a more
| linear freq response.
| platz wrote:
| well, the orion image you linked doesn't look like it's
| been over-sharpened, in contrast to the OP image. I'm not
| saying there's a way to tell just by eyeballing it, but
| that's what it smells like.
| pdpi wrote:
| It has a distinctly HDR-y look to it but no meaningful
| sharpening. I think the grain is just a fruit of having noisier
| sensors back in 2009
| gbrown wrote:
| In astrophotography there's (almost) no such thing as
| "natural". It's definitely an aesthetic, but it's based on
| "real" data.
| platz wrote:
| It can be true that it's both based on real data and that
| there is an aggressive amount of post-sharpening applied.
| gbrown wrote:
| This is true, but it's also true that making faint features
| visible (like the dark, dusty regions) often requires the
| use of local contrast, sharpening, and masks.
|
| Also, in the case of this specific image, I think it's
| important to note just how deep the images are - they're
| processed for high resolution in the individual components,
| so the mosaic has an absolutely huge resolution. When
| downscaled to look at the whole thing zoomed out, that
| might give some of the impression of over-sharpness.
| jonplackett wrote:
| Holy crap the universe is massive.
|
| It occurred to me the other day that there's barely any science
| fiction that even occurs outside our own galaxy (Star Wars being
| the exception that proves the rule). And if it does it's usually
| something from Andromeda right 'next door'.
|
| Even Star Trek only leaves the galaxy maybe one time, and that
| requires the help of Q.
| m463 wrote:
| Too bad it's so far away.
|
| There's that saying... too young to explore the world, too old
| to explore the universe.
|
| When our children's children learn to extend their life, or
| figure out some sort of suspended animation, or pload their
| brain... what wonders they will see.
| divbzero wrote:
| This is absolutely incredible. Thank you.
|
| I would love to see the mosaic extended below Cassiopeia to
| include the Andromeda Galaxy.
| m463 wrote:
| Wow, he _started_ with a Canon EF 200mm f1.8 and worked his way
| UP.
| jakobdabo wrote:
| On a camera in manual mode if you increase the exposure time, you
| must compensate the increased amount of light coming to the
| sensor by decreasing the aperture or the ISO. Can anybody please
| explain, how is it possible to have such a long exposure without
| overexposing the image?
| Miraste wrote:
| If you want longer exposures than your lowest ISO can handle
| you can also use neutral density filters, which go over the
| lens and reduce the amount of light hitting the sensor.
|
| https://en.wikipedia.org/wiki/Neutral-density_filter
| gbrown wrote:
| Astrophotography is less like photography and more like
| scientific data acquisition.
|
| To specifically answer your question though, this is "1250
| hours of exposures" and not "a 1250 hour exposure".
| ksml wrote:
| Note that these images are made from many exposures that are
| then processed and combined, and the _total_ exposure time is
| given. The individual exposure times were probably long, but I
| 'm guessing on the order of minutes, not hours. (Actually, if
| you photograph stars with an exposure time that is too long,
| then you get star trails in the image.)
| Normal_gaussian wrote:
| Trails appear very quickly, at focal lengths of around 20mm
| (typical dslr kit lens) they are obvious in 20-30 seconds,
| with a 100mm lens (start of telephoto range) they are obvious
| in 3-5 seconds. This of course depends on the res of your
| camera (I shoot with an 8MP and a 24MP).
|
| To get rid of the trails you need a tracking mount. The
| better the mount the smoother and longer it tracks.
| Astrophotography is expensive...
| gbrown wrote:
| > if you photograph stars with an exposure time that is too
| long, then you get star trails in the image
|
| He was using a tracking mount. At 200mm you can't image for
| more than a few seconds without trailing.
| aylmao wrote:
| By using very low ISOs. You want to use the lowest ISO possible
| because the lower the ISO the less noise in the picture, and
| noise in the night sky can be very noticeable since you are
| photographing a ton of tiny dots against a black background.
| samstave wrote:
| Why arent we having a full stream of space pics constantly coming
| from the thousands of satellites we have in the sky?
|
| Why do we have to wait on a backyard astronomer to post something
| like this?
| nogbit wrote:
| Because those sats are pointing down at us.
| samstave wrote:
| :-) I know, it was the proverbial "why"
| neha_t wrote:
| Good time to take this to an auction and sell as an NFT :)
| jointpdf wrote:
| Earthlings that liked this link may also enjoy:
| https://www.astrobin.com/iotd/archive/
|
| (massive archive of amateur astrophotography images +
| equipment/processing details)
| ClosedPistachio wrote:
| The full panorama is spectacular:
| https://1.bp.blogspot.com/-LK-I6WIOp8w/YE3ejvMEc8I/AAAAAAAAS...
| amelius wrote:
| Are those colors real, or just synthesized by the visualization
| technique?
| giuliomagnifico wrote:
| Real colors is always a particular definition, because
| everyone of us see the colors differently, for the
| astrophotography is another different thing because the
| colors are made by frequencies of the light spectrum. Try to
| read this for more info: http://dslr-
| astrophotography.com/right-colors-astrophotos/
|
| > Conclusion on color calibration:
|
| "There are multiple definitions of what it means to have
| 'correct colors' in your astrophotos. Therefor this always
| will be a matter of personal preference and everyone will
| have to figure out what their own vision on the matter is and
| pick a method of calibrating the colors accordingly"
| ImprovedSilence wrote:
| Very interesting article, well worth the read.
| dr_orpheus wrote:
| They are synthesized, from the article "Image in mapped
| colors from the light emitted by an ionized elements,
| hydrogen = green, sulfur = red and oxygen = blue."
| amelius wrote:
| What do the real colors look like?
| enriquto wrote:
| just look up to the sky at night. They are so dim that
| you cannot really distinguish their hue.
| amelius wrote:
| When I look up to the sky at night I just see reflections
| of the lights emitted by my city. It often is an orange
| glow.
| JohnJamesRambo wrote:
| This is too dystopian this early in the morning.
| ImprovedSilence wrote:
| To the naked eye from earth, it looks black and white,
| and you wouldn't be able to see that much detail. What
| they "really" are is more complicated, as indicated by
| other responses.
| elteto wrote:
| Hard to tell without being closer :) Nebulae might not
| even emit that strongly in the spectrum that we humans
| can see. A lot of these pictures are taken with special
| narrowband filters that isolate wavelengths for specific
| components, such as Oxygen or Hydrogen. Then these
| narrowband images are combined and assigned to the R, G,
| B channels. A popular palette is the "Hubble Palette"
| because, well, that is what the Hubble uses.
| nsilvestri wrote:
| Depends on the filter used. I am assuming the author is
| using one of these hydrogens (probably Ha) and O-III and
| S-II. Each of these black-and-white images with this
| filter are used as the data for a single RGB channel in
| an image. Their wavelengths are, and would like like to
| the naked eye [1]:
|
| Ha (656 nm) bright red
|
| Hb (486 nm) deep blue
|
| O-III (496 nm and 501 nm) greenish blue to green
|
| S-II (672 nm) deeper red
|
| The color mapping the author uses is called the Hubble
| Space Telescope pallet, where hydrogen = green, sulfur =
| red, and oxygen = blue.
|
| [1] http://pages.cs.wisc.edu/~yetkin/code/wavelength_to_r
| gb/wave...
| dylan604 wrote:
| Depends on what you mean by real colors. The light is so
| faint, that human eyes cannot make it out. However, long
| exposure photography with a CMOS sensor will bring out
| colors without any filters. Are those the real colors?
| There are tons of examples of these types of shots.
| Search for The World At Night (TWAN) for some great
| examples
| mnw21cam wrote:
| That's not the full panorama. Try
| https://1.bp.blogspot.com/-TqRxEAjrDYI/YFCLF-H8K3I/AAAAAAAAS...
| instead.
| simonh wrote:
| I like this one:
| https://www.eso.org/public/images/eso1242a/zoomable/
| lolptdr wrote:
| Damn, this is impressive. Wish there were more annotations of
| other notable sky objects in addition to what's shown.
| mnw21cam wrote:
| Try https://1.bp.blogspot.com/-_0wX_SbN2V0/YFBrGdGEasI/AAAA
| AAAAS... for an image with more annotations.
| jcims wrote:
| For folks passing through it's the full panorama but at 7% of
| the full resolution.
| soheil wrote:
| I'm so glad we're used to clouds on Earth and that our human
| brain evolved to intuitively understand them because as it
| happens the cosmos are just like clouds. It'd suck if we looked
| at them and were lost in their perplexity.
| realo wrote:
| When I look at this, it is hard to believe that life (and
| intelligent life) only exist on planet Earth...
|
| Very hard to believe.
| ekianjo wrote:
| Thats not hard to believe once you understand how unprobable
| life seems to be and especially in the very long term. The
| universe is a very violent place and cosmic events act as great
| filters all the time.
| divbzero wrote:
| Then again, this photo mosaic spans just one arm of one
| galaxy in the visible universe.
| 4silvertooth wrote:
| When I look at this I feel life must be common. Maybe some dot
| in there must be planet full of dinasaurs.
| xaedes wrote:
| If we would find a huge natural mirror or similar - far away,
| maybe we would be able to see our past earth still populated
| with dinosaurs.
| layer8 wrote:
| There are roughly 10^23 stars in the observable universe. We
| really have no idea how likely intelligent life is to evolve.
| It could be 1/10^10 per star, in which case intelligent life
| would be a fairly typical thing (dozens in the milky way), or
| it could be just 1/10^100, in which case we could be the only
| ones. Unlikelihoods can compound very quickly.
| nonfamous wrote:
| Love the use of the apparent size of the moon for scale. Really
| gives you an awesome sense of what you're _not_ seeing in the sky
| in cities with your own eyes.
| CliffStoll wrote:
| Superb work, astonishing dedication, and a beautiful result!
|
| High congratulations!
| f430 wrote:
| stupid question but how did we realize we were in a galaxy and
| how are we able to take pictures of it???
| cozzyd wrote:
| Can I buy a large print of this somewhere?
| gilbetron wrote:
| If you can get this printed on metal, it would look amazing. My
| wife is IT for an astronomy dept and they have metal prints all
| over the place that are just stunning!
| m463 wrote:
| I think it would be nice to have it as wallpaper that slowly
| navigates the galaxy while I'm working.
| pjmorris wrote:
| I have the same question!
|
| Related question: If someone wanted to print something like
| this for themselves, how would they go about it? Say, I have an
| image or photo and I wanted to make a high quality print
| suitable for framing and hanging on, say, my office wall. Is
| this an 'Ask HN' question?
| dsr_ wrote:
| Do you want the cheapest way to do it or the highest quality,
| or something in between?
|
| If you have an image that fits in less than 20x30", CostCo or
| another mass printing service can do it for $10. They won't
| do any adjustment, so the colors may be off a little.
|
| They'll print on canvas to 30x40" for $120. That's only
| 150dpi; it doesn't look great up close, but is pretty good
| from 3+ feet away. Again, colors are what they are.
|
| High quality printing is a thing that you talk about with a
| professional printer (the person, not the machine) for each
| job. Prices generally start at $100 or so for smallish
| prints, and can go up to $1500 or more for large, permanent-
| art quality work.
| pjmorris wrote:
| More like the highest quality, but probably price sensitive
| which means 'somewhere in between.' I've thought about
| taking a test image to Costco to see how it comes out on
| metal, but figured that there might be higher quality
| options. Thanks for your examples, looking to see what
| others post.
| dsr_ wrote:
| Remember that when you work with a good image printer,
| you're paying for their expertise and time -- and you
| won't have to re-print failures, because they'll consult
| with you to get it right.
|
| One friend of mine spent several hundred dollars at an
| online printer in $40 increments trying to get it right.
| Cerium wrote:
| I have worked with Inprintz (https://inprintz.com) they are
| in the south bay area. They can do prints on photographic
| media up to 5 foot by 10 foot.
| cozzyd wrote:
| I mean, you can always segment it into several smaller prints
| and then stitch them together (carefully!), but I'd rather
| the author get some cut of it than me doing it myself at
| Walgreen's or Staples.
| fixie wrote:
| I've done high quality large prints from
| https://www.bayphoto.com/. They did a great job and have
| different archival paper to choose from. Got the print from
| there and used a local framing shop to get it professionally
| framed.
| elteto wrote:
| Second bayphoto for metal prints. I have gotten stunning
| results.
| dding wrote:
| Wow amazing work! The scale of this project reminds me of another
| photographer's five year project of creating a 2.5 gigapixel
| photo of Orion: https://orion2020v5b.spaceforeverybody.com/
| kgran wrote:
| Looking at these pictures, I've began to ponder how much of an
| influence the night sky has been in religion and mythology
| throughout the millennia.
| uhtred wrote:
| Agreed. I very recently was thinking about how humans up to a
| few hundred years ago must have seen the most breath taking
| night skies. Imagine a native American standing in a clearing
| at night 2000 years ago, with zero light pollution, looking
| at the night sky and just wondering what it is all about.
| wahern wrote:
| Even w/ a clear desert sky hundreds of miles from the
| nearest city (e.g. middle of Nevada), the sky looks
| _nothing_ like these pictures. Astrophotography uses
| exposure times many multiples--and usually several orders
| of magnitude--longer than the human eye.
|
| Can you see the Milkyway? No, not really; not without
| prompting. If you have no idea what to look for, the disc
| is just a barely imperceptible, slight increase in
| otherwise meager (relative to astrophotographs) star
| density. I've never seen it, nor other constellations,
| because I don't really know what to look for, though I've
| spent many hours staring up at the sky from various places,
| including extremely remote desert and mountain locales--
| Western U.S., Northern Mexico, Mongolia, Ecuador, Chile,
| etc.
|
| Of course, there's no way to understand the awe and
| wonderment somebody lacking our knowledge, experience, and
| expectations may have experienced. Especially if they had
| never seen an astrophotograph.
|
| EDIT: Actually, now that I think about it, I wonder if
| astrology, navigation, and astronomy might have developed
| more slowly if the human eye had greater fidelity. With
| only several thousand stars visible (much fewer readily
| discernible, especially if you're not an adolescent w/
| fresh corneas), the _motion_ of stars probably stands out
| more. Imagine trying to recognize and track the planets on
| a background as dense as an astrophotograph. Where to
| start? Would you even recognize the relative motion? People
| had much fewer distractions during nighttime back then, but
| it still seems substantially more daunting.
| quesera wrote:
| I agree with your larger premise, but:
|
| > Can you see the Milkyway? No, not really
|
| This is not my experience. I have seen the Milky Way very
| clearly from a few locations in the US. None are
| particularly remote -- all are just a few hours drive
| from the large cities I've lived in. Winter months are
| clearer than summer.
| jjnoakes wrote:
| Yeah I agree. Not only have I seen the milky way, but
| I've seen andromeda with my naked eye from the right
| place on the right night, within a day's drive from very
| populated cities.
| mathewsanders wrote:
| +1. I've not seen it for 10 years (since I've lived in
| the United States) but growing up in New Zealand, looking
| up at the Milky Way with your naked eye, it's definitely
| clear the increased density of stars. Doesn't look
| anything like photos, but very beautiful.
| dekhn wrote:
| The path to modern astronomy went like this: cultures that
| lasted a long time (Multiple hundreds of years) typically
| developed observatories that defined the yearly calendar as
| well as dates of religious observances. Many times, their
| observations got very accurate and they could predict various
| things, although surprising stuff still happened. Eventually,
| civilizations lasted through multiple solar eclipse cycles
| and noticed they were periodic (keeping great records for
| hundreds of years and maintaing a class of people who can
| work with them is nontrivial). This eventually led to people
| being able to predict nearly all planet's motions with
| surprising accuracy (see the antikythera mechanism).
|
| So I think it's had a huge influence ,and one that ultimately
| led to a scientific understanding of the cosmos. At this
| point, JPL can predict the location of nearly every major
| solar object for decades into the future and the main
| challenege is determining whether object movement is truly
| chaotic.
| titzer wrote:
| And in the modern world, we are blind to it because of light
| pollution. It's sad. One of the most amazing experiences
| ever, a truly dark, clear sky at night, is only accessible if
| you travel off-continent.
| birktj wrote:
| That is exactly the feeling I get the couple of times when I
| am out hiking hiking and see the most spectacular winter
| night sky. The feeling of being in the middle of nowhere and
| seeing the dark sky with an uncountable number of stars is
| indescribable. I believe it is a great loss of modern society
| and I really hope we are able to do something about it, we
| could do just fine without most of the street lighting we
| have today.
| phaedrus wrote:
| Something about that Orion photo in particular makes it seem
| beyond belief that there is not other life around other stars
| in the galaxy.
| quesera wrote:
| For me, it was this image and story that removed any shred of
| doubt:
|
| https://en.wikipedia.org/wiki/Hubble_Deep_Field
|
| The tiny speck of dust that is our whole world is less than a
| grain of sand on the beaches of the universe.
|
| We are not alone.
|
| Which doesn't mean that we would want to meet any of our
| neighbors!
| clon wrote:
| This is fantastic.
|
| I immediately wondered how he managed to seamlessly mosaic
| together what is surely hundreds of images and thousands of
| subs. Here are the details:
| https://space4everybody.com/processing-details/
|
| And equipment: https://space4everybody.com/technical-details-
| equipment/
|
| Nothing too fancy (in astrophotography relative terms). A
| decent refractor and mono camera (such parameters have come
| down in price by 2-3 times, ASI2600MM is comparable) and most
| importantly, a solid pier/mount. 267 Individual
| panels (including reshoots) 12,816 Individual light
| frames 65,000 x 35,000 in it's entirety 5 States
| traversed to image 640.8 Imaging hours 500+ Editing
| hours 2.5 Gigapixel Image 1.6 Pixel scale 5
| Years 1 Mosaic
|
| Just WOW
| benfarahmand wrote:
| This is amazing! When taking long exposures like this over a
| significant amount of time, does anyone know how astronomers
| account for stellar parallax and/or the sun's orbit in the milky
| way? Are these factors too small to affect long exposure photos?
| And if they are too small to affect a long exposure photo, at
| what point does it become an issue?
| titzer wrote:
| Stellar parallax isn't a big effect. It wasn't even observable
| until the 1800s. Even the Hubble cannot measure parallax past
| about 10,000 lightyears, which is about 10% of the size of the
| Milky Way. For earth bound telescopes at this scale, it's
| totally negligible.
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(page generated 2021-03-17 23:00 UTC)