January 3, 2008 7:16 AM   Subscribe

The images produced by today's ordinary amateur astrophotographer rival those produced by the big observatories only a decade or two ago. (This "Two Comets" image alone is worth a look. <-Rollover for close-ups of the comets.) You can get very good results with far simpler equipment, however - even with "old-fashioned FILM". Looking for the BEST skies for astrophotography? If you aren't a weenie, you might try Dome C, Antarctica.

Some call this "astroporn" because they feel such images raise expectations for what one will see through the telescope (visually) to unrealistic levels.

See also: Starting Out in Astrophotography & Astrophotography 101.
posted by spock (19 comments total) 21 users marked this as a favorite
Spock, great post and great links.

Some more great astrophotos here. This site also tells you all of the exposure conditions and the cameras used, though this site seems to be a bit more on the pro side. The camera a lot of them use is the SBIG STL 11000M.
posted by Pastabagel at 7:26 AM on January 3, 2008

And Stephan Seip's personal site is amazing.
posted by Pastabagel at 7:36 AM on January 3, 2008

This guy has some nice work, too. And yes, a lot of serious astrophotographers (that I have linked to) are using high-end CCD cameras, but it is interesting to note that pretty good results can be achieved with more modest budgets and many are using (not a CCD at the eyepiece) but basic DSLRs piggybacked on their motor-driven scope. See also: Canon EOS 300D/350D/400D (Digital Rebel) Astrophotography and Astrophotography Techniques. Others put the DSLR at the eyepiece for "prime focus" astrophotography. Some people like hacking their DSLR to make it even better for astrophotography. So why is everybody using Canons?
posted by spock at 7:40 AM on January 3, 2008

Who blew M33? Are WE NEXT?
posted by SPUTNIK at 7:42 AM on January 3, 2008

Perhaps you think you can't do this because you live in the middle of a big city (1.6 million).
posted by spock at 7:46 AM on January 3, 2008 [1 favorite]

I think the reason everyone has used canons in the past is because they actually put out a camera specifically for astrophotography, the EOS 20Da, now discontinued. This camera had much better IR response and would lock up the mirror to allow live manual focusing of the image.
posted by Pastabagel at 7:49 AM on January 3, 2008

Among amateur astrophotographers, it is popular to hack the Canon camera firmware to achieve the mirror lockup capability (discussion). My "hacking their DSLR" link, above, describes removing the IR filter (not for the faint-hearted). There are also people who will do this, as a service (for a price), who advertise on the astronomy forums. That is only important if you want to capture that part of the spectrum (only necessary for capturing certain types of astronomical objects).
posted by spock at 7:59 AM on January 3, 2008

Just got a Canon dSLR and a (small) refractor telescope - I may try some of these techniques (don't know if the scope is up to it though). Thanks!
posted by Mister_A at 8:00 AM on January 3, 2008

It is worth noting that most of the advances in astrophotography involve the techniques for post-processing the digital images. Image Stacking, for example, allows one to duplicate the effects of a (tedious/difficult) long exposure with short exposures. A google search for "astrophotography" and "image processing" will get you started. Much of the software you will need is free.
posted by spock at 8:25 AM on January 3, 2008

Lucky imaging. Previously.
posted by weapons-grade pandemonium at 9:06 AM on January 3, 2008

wow spock, What a nice surprise. When I opened that first page of your "image" link, scrolled to planets over Stonehenge, my eyes welled up. Such beauty. The atmosphere is palpable in that shot, sitting in my chair here in NYC I can feel that intense blue verging on purple like a Maxfield Parrish twilight (confession, I've been over at YouTube and could be under the influence of Celine Dion singing It's a New Day, a bit like getting stoned on the cooking sherry, a high I'm slightly ashamed about).

And then the site owner, this wonderful Philip Perkins, adds an elegant annotation. wow. phew, a heady mix. Hardly dare head over to his Milky Way, I might faint.

And then there's the holy shit factor over that Russell Croman site. Silly, that teen exclamation, "That's sick!" comes to mind. It's overwhelming. wow doesn't do it justice. I need astrological Captain Haddockisms: Thundering incandescent nucleosity! Apoplectic apoapsis! Cosmulartastic!
posted by nickyskye at 10:48 AM on January 3, 2008

ps astroporn is a great term. Gives porn stars a whole 'nother meaning, from globular clusters to asteroids, it puts the kink into chromatic aberration, viagra into a heliacal rising and the meat into meteors. This new generation asstronomers sure is naughty.
posted by nickyskye at 11:08 AM on January 3, 2008

Dang, nickyskye, you must be a writer (or at the very least, put English Major on par with Ursa Major & Canis Major).
: )
Great comments.
posted by spock at 11:17 AM on January 3, 2008 [1 favorite]

Amateur astropornograhers photograph massive globular clusters. Great astropornographers photograph hot young binary stars. But a truly brilliant astropornographer gets a shot of a naked singularity.
posted by kyrademon at 1:24 PM on January 3, 2008 [1 favorite]

From the Dome C link:

Astronomers currently know how to interfere 4 telescopes into a common image. The Keops projects of the Nice University plans no less than 36 telescopes of 1.5 meters organized in 3 concentric circles, the outer ring having a diameter of 1km. With a diameter of 1.5m and the excellent quality of the seeing at Dome C there's no need for adaptative optics on each individual scopes. This setting would be able to resolve the Sun-Earth distance at 1kparsec (the thickness of the Milky Way). The principal application is to detect not only exoplanets (we already know several hundreds larger than Jupiter) but still undetected exo-Earths with a 90% probability. This kind of direct optical observation relies mainly on long exposure times to increase the signal to noise ratio and here in Dome C during the long winter nights it's possible to have exposure times above a month of duration with a 3 month window of perfect observing conditions ! Such a long exposure would bring the quality of the S/N to values never dreamed of before.

So would they be able to obtain images of those exoplanets with this arrangement?

Just curious.

Awesome post, spock!
posted by jason's_planet at 2:39 PM on January 3, 2008

Thanks spock, blame my happy verbosity on your excellent post.
posted by nickyskye at 3:22 PM on January 3, 2008

Here's a great example of the type of improvement that amateurs have been able to get using rather simple/inexpensive equipment:

Before (jpg image)
After (jpg image)

(Both images came from this page, which has more info about them.)

"Before" is a typical image of Mars you might have seen from amateurs using basic, inexpensive backyard equipment up through the 90s.

"After" is a typical Mars image of the quality posted by amateurs with basic, inexpensive equipment (and a bit of patience) today.

"After" is taken with a 4-inch scope and Philips ToUcam.

You can buy a ToUcam on Ebay right now for $13.78, an telescope adapter for it for $40, and your nice little 4- or 6- inch telescope for as low a few hundred bucks.

This is a very interesting and accessible hobby right now.

I'm too lazy to take photos myself but I'm on the various email lists (Mars, Jupiter, Saturn, etc.) of the Association of Lunar & Planetary Observers, which keeps my emailbox full of links to the latest interesting image whenever a particular planet is visible.
posted by flug at 4:22 PM on January 3, 2008

jason's_planet, the short answer to your question is ... they sure hope so.

If I am understanding my-girlfriend-the-astrophysicist correctly (which is by no means guaranteed), multiple-mirror telescopes like that tend to have great resolution - roughly speaking, how close to one object you can see another object - but fall down on sensitivity - how dim an object you can see. Since planets are both dim, relatively speaking, and really close to their stars, from our perspective, you need both to see them.

The problem occurs because (I believe, but am not totally sure) resolution is determined at least in part by how wide an area you can cover, but sensitivity is determined (again, at least in part) by how much actual reflective surface you have. You can spread out, say, five 3-meter mirrors across a wider area than a single 8-meter mirror, but your five 3-meter mirrors combined will still have much less total reflective area, because the area goes up by the square of the radius.

They seem to be trying to solve this problem in two ways:

1) Using a boatload of mirrors. Thirty-six 1.5-meter mirrors gives you a total reflective area in the range of a single 9-meter telescope. That's darn good. But bear in mind people have been trying to directly image extrasolar planets with 8-or-so-meter telescopes for a while now without a lot of success. So they're also:

2) Building it an area where, apparently, the seeing is so good that they can just leave it looking at a single point for a month, gathering as much light as it can, without worrying about the weather, which is another way to improve sensitivity.

It'll be interesting to see if it works.
posted by kyrademon at 7:19 PM on January 3, 2008

OK. Got it.

Thank you, kyrademon.
posted by jason's_planet at 9:37 PM on January 4, 2008

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