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Stereoscopic images of Titan's surface constructed
CozmsBrpng writes "If you can successfully view stereoscopic images then you can behold the surface of Titan in all its grainy 3D glory. And, in case you missed it, you can also listen to a human ear-friendly version of the descent radar and the winds in Titan's atmosphere courtesy of the DISR team at The University of Arizona."
I find it easier to print stereograms like these. Perhaps even re-position them really close to each other in GIMP before printing it out. they seem to be easier to "lock on" on paper than on screen. There's just no way I can see them on screen.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
You already have the equipment. Just cross your eyes while looking at it until your eyes focus and click. You'll know what I mean when you get it right.
After all, I am strangely colored.
Yea, but there's enough relief to see that the black "channels" don't follow it. On the first pic they look like some of them run cross-slope, and on the last pic it looks like they run on the ridgelines, as if we were looking at something bulging up from below.
I'm good at them, and I still couldn't get much out of those besides a headache. Here's a bunch of better ones, just to show that they don't suck universally.
Work is punishment for failing to procrastinate effectively.
Also for some people it may help of you open the images in a photo editor, cut out one of the images and move it to the other side, then all you need to do is cross your eyes until the two images meet. I've always found it easier and less straining on the eyes if you do it this way.
ADULT CONTENT
Just don't blame me when you can't see straight for a week afterwards.
Personally, I prefer wiggle images, where you make an animated GIF of two close-by images. You don't have to hurt your eyes, and it gives you a good idea of depth. Here's a web site with several "wiggle images" made from Mars Rover data:
http://space.brownpau.com/mars-rover-wiggles/
1500 imaginary mod points to whoever uses GIMP or Photoshop to cut the individual images out of the photos of Titan, makes an animated GIF out of them, and posts them online.
You need to go the reverse of cross-eyed to look at stereoscopic images correctly
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If you have to strain your eyes then you are doing it the wrong way and you wont get a very good 3D effect
-Normal way of looking at something-
object
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eyes
-Correct way to looks at a stereoscopic image- (very relaxed eyes)
object
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eyes
-Incorrect way- (going cross-eyed)
object
\
/ \
eyes
You hit upon two very salient truths about the Huygens probe. The main imaging instrument on Huygens is the Descent Imager Spectral Radiometer (DISR). It contains only a single CCD. The various lens assemblies are connected to the main CCD by a series of optical fibers, each shines light on a different region of the CCD. The CCD is 512x520 pixels though about half of that is reserved as a storage section, the left over 256x520 pixel area is used for the imagers and spectrometers. The visual imagers of the DISR intrument are the High Resolution Imager (HRI), Medium Resolution Imager (MRI) and the Side Looking Imager (SLI). There's also two spectrometers, the Upward-Looking Visual Spectrometers (ULVS) and the Downward-Looking Visual Spectrometer (DLVS). Finally there's space reserves for the Solar Aureole camera which is used to measure sunlight streaming through the atmosphere to determine the size of particles within it.
The HRI is 160x254, the MRI is 176x254, and the SLI is 128x254 pixels each. Larger images have to be assembled as mosaics and even these aren't going to be large enough to compete with the megapixel images from the MERs. The Pancams and Navcams on the MERs are 1024x1024 each and have essentially a full range of motion so really nice panoramas are easy to create. The DISR is fixed on Huygen's chassis.
Bandwidth is also a tremendous issue with Huygens. The Huygens probe only hasd a 4800bps datalink to Cassini and has to transmit all of its images within two and a half hours. Even with its limited data rate Huygens was able to transmit 350 images back from Titan which is rather impressive.
So it is a combination of geometry, bandwidth, and limited technology. Also remember that despite these images being relatively stark in comparison to MER images they contain tons of very valuable information. When researches have had more time to process Huygens images they will get prettier. Until then they're going to remain relatively bland to laymans' eyes but terribly exciting to scientists.
I'm a loner Dottie, a Rebel.
To make things easier, here is a reconstruction with instruction.
Just sit back about 2 feet from the monitor and try to cross your eyes till you get something similar to the bottom group.
If there is a good response to this, I'll do the others.
Otherwise, you may be able to do them on your own after training with this:
Stereo Image of Titan with Training bars
Yes you're on the ball for the fact that the images don't allow good quality stereo vision, but I don't agree with you in your assertion that divergent stereo is harder to do than cross-eyed stereo...
Crossing (converging) of the eyes induces extra accommodation (an increase of the eye's dioptrical power to bring closer objects into focus), thus blurring the image and (for me anyway) making it much harder to see the stereo image. De-converging your eyes (done simply by imagining a point further away than the monitor... as in staring blankly ahead) allows an unblurred image.
I think claims based on peoples personal experience rather than on pure fact (such as "divergent stereo is almost impossible") are highly unprofessional, and being a registered Australian optometrist I could use my position to argue that divergent stereo is much easier based on my personal experience, but I wont, as the fact is the ease of di/con-verging the eyes is a variable and as such, some people find it easier to do one and not the other.
I know many fellow optometrists that find divergent stereo easier, thus I have proved your mother wrong, and hope it serves to make you more cautious before posting assertions that you beleive are "facts".
As to why the images are poor stereoimages, they are taken from a very large distance. Human stereovision isn't designed to produce accurate 3D of far away objects, but moreso close (at hand) objects. Thus the value of images taken from a long distance as stereoscopic images is dimished.