APOD: Stereo Mars near Opposition (2022 Dec 03)

[APOD Robot]

Stereo Mars near Opposition

Explanation: Mars looks sharp in these two rooftop telescope views captured in late November from Singapore, planet Earth. At the time, Mars was about 82 million kilometers from Singapore and approaching its opposition, opposite the Sun in planet Earth's sky on December 8. Olympus Mons, largest of the volcanoes in the Tharsis Montes region (and largest known volcano in the Solar System), is near Mars' western limb. In both the images it's the whitish donut-shape at the upper right. The dark area visible near center is the Terra Sirenum region while the long dark peninsula closest to the planet's eastern limb is Sinus Gomer. Near its tip is Gale crater, the Curiosity rover's landing site in 2012. Above Sinus Gomer, white spots are other volcanoes in the Elysium region. At top of the planet is the north polar cap covered with ice and clouds. Taken about two days apart, these images of the same martian hemisphere form a stereo pair. Look at the center of the frame and cross your eyes until the separate images come together to see the Red Planet in 3D.

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[FLPhotoCatcher]

Cool! Though it would be easier to see it in 3D if the two images of Mars were closer together in the pic.
Also, the clouds and ice cap look different because the images were taken about two days apart. Why not a half hour or so apart?

Here's a 3D photo I took a few years ago. It's also viewed by crossing your eyes. Click on it to get the best version.
I used my camera and my brother's camera set to automatically take one photo every 10 seconds. They were not well synchronized, so I only got a few photos with the same bolts of lightning in them.

[Joe2233]

Olympus Mons is NOT a volcano.

[Chris Peterson]

Olympus Mons is NOT a volcano.

There is virtually no doubt that Olympus Mons is a volcano. Many individual lava flows are identifiable, along with geological structures like dikes and lava tubes associated with lava flows. And the mountain is basaltic, as determined spectroscopically.

[orin stepanek]

Curiosity

I wasn't really impressed with my cross-eyed view; gave me a headache!

This impressed me! A spiraled North Pole; that's a freak of nature!

[DonB312]

Here's a 3D photo I took a few years ago. It's also viewed by crossing your eyes. Click on it to get the best version.
I used my camera and my brother's camera set to automatically take one photo every 10 seconds. They were not well synchronized, so I only got a few photos with the same bolts of lightning in them.

That's a very nice photo. It's an interesting perspective on the storm. Thanks for sharing it with us.

[johnnydeep]

Sadly, I'm still incapable of crossing my eyes enough to get the images to overlap. I can only get them to partially overlap.

[Dark skies of Sing!]

So this was shot from Singapore, the most light-polluted city in the world.* That's amazing.

(*) If you ain't been there just Google "Singapore light pollution". It's a great city for a lot of things but stargazing usually doesn't come to mind.

[Chris Peterson]

So this was shot from Singapore, the most light-polluted city in the world.* That's amazing.

(*) If you ain't been there just Google "Singapore light pollution". It's a great city for a lot of things but stargazing usually doesn't come to mind.

Light pollution doesn't matter for planetary imaging. Only steady skies.

[Chris Peterson]

Sadly, I'm still incapable of crossing my eyes enough to get the images to overlap. I can only get them to partially overlap.

Unless there is something seriously wrong with you, you can most definitely cross your eyes enough to overlap the images. The amount of crossing necessary is like looking at your finger 5 or 6 inches from your face. The problem you are likely having is convincing your eyes to focus properly when they are crossed, and your brain thinks what you are looking at is closer than it really is.

[johnnydeep]

Sadly, I'm still incapable of crossing my eyes enough to get the images to overlap. I can only get them to partially overlap.

Unless there is something seriously wrong with you, you can most definitely cross your eyes enough to overlap the images. The amount of crossing necessary is like looking at your finger 5 or 6 inches from your face. The problem you are likely having is convincing your eyes to focus properly when they are crossed, and your brain thinks what you are looking at is closer than it really is.

I've got nothing seriously wrong with my eyes or brain that I know of (though some friends of mine might disagree). So do you mean if I can keep my finger in focus when it's held 5 or 6 inches in front of me, then, in theory, I should be able to see stereographs such as this? If so, the good news is that I can focus my finger just fine. So, I guess I'll just keep trying to see these stereo images.

[Chris Peterson]

Sadly, I'm still incapable of crossing my eyes enough to get the images to overlap. I can only get them to partially overlap.

Unless there is something seriously wrong with you, you can most definitely cross your eyes enough to overlap the images. The amount of crossing necessary is like looking at your finger 5 or 6 inches from your face. The problem you are likely having is convincing your eyes to focus properly when they are crossed, and your brain thinks what you are looking at is closer than it really is.

I've got nothing seriously wrong with my eyes or brain that I know of (though some friends of mine might disagree). So do you mean if I can keep my finger in focus when it's held 5 or 6 inches in front of me, then, in theory, I should be able to see stereographs such as this? If so, the good news is that I can focus my finger just fine. So, I guess I'll just keep trying to see these stereo images.

Close, but not quite. The amount of crossing is consistent with looking at an object a few inches in front of your eyes. But you're focusing on something that's another foot or so behind that. That's the trick. Normally, your eye position and eye focus are tied together without you needing to think about it. Aim your eyes at something six inches away, and they will focus for a distance of six inches. Here you're aiming for six inches but focusing for eighteen. That is something under voluntary control, but it can take a bit of practice to figure it out.

[FLPhotoCatcher]

Sadly, I'm still incapable of crossing my eyes enough to get the images to overlap. I can only get them to partially overlap.

Unless there is something seriously wrong with you, you can most definitely cross your eyes enough to overlap the images. The amount of crossing necessary is like looking at your finger 5 or 6 inches from your face. The problem you are likely having is convincing your eyes to focus properly when they are crossed, and your brain thinks what you are looking at is closer than it really is.

I've got nothing seriously wrong with my eyes or brain that I know of (though some friends of mine might disagree). So do you mean if I can keep my finger in focus when it's held 5 or 6 inches in front of me, then, in theory, I should be able to see stereographs such as this? If so, the good news is that I can focus my finger just fine. So, I guess I'll just keep trying to see these stereo images.

If you wear glasses that help you see objects that are farther away, those may help keep the pic in focus as you are crossing your eyes. I generally get about 24+ inches from the screen when viewing the 3D pic.

[orin stepanek]

Sadly, I'm still incapable of crossing my eyes enough to get the images to overlap. I can only get them to partially overlap.

look at the photo of Mars; cross your eyes until you have three pics of Mars instead of two; the middle Mars is the one that is stereo! hope that helps!

[johnnydeep]

Unless there is something seriously wrong with you, you can most definitely cross your eyes enough to overlap the images. The amount of crossing necessary is like looking at your finger 5 or 6 inches from your face. The problem you are likely having is convincing your eyes to focus properly when they are crossed, and your brain thinks what you are looking at is closer than it really is.

I've got nothing seriously wrong with my eyes or brain that I know of (though some friends of mine might disagree). So do you mean if I can keep my finger in focus when it's held 5 or 6 inches in front of me, then, in theory, I should be able to see stereographs such as this? If so, the good news is that I can focus my finger just fine. So, I guess I'll just keep trying to see these stereo images.

Close, but not quite. The amount of crossing is consistent with looking at an object a few inches in front of your eyes. But you're focusing on something that's another foot or so behind that. That's the trick. Normally, your eye position and eye focus are tied together without you needing to think about it. Aim your eyes at something six inches away, and they will focus for a distance of six inches. Here you're aiming for six inches but focusing for eighteen. That is something under voluntary control, but it can take a bit of practice to figure it out.

So, focus on something eighteen inches away but then shift your gaze to this stereogram 6 inches away? PS - I have no problem seeing those "magic eye" images. Are the viewing/focusing methods similar?

[johnnydeep]

Sadly, I'm still incapable of crossing my eyes enough to get the images to overlap. I can only get them to partially overlap.

look at the photo of Mars; cross your eyes until you have three pics of Mars instead of two; the middle Mars is the one that is stereo! hope that helps!

Sorry, it's just not happening for me.

[Chris Peterson]

I've got nothing seriously wrong with my eyes or brain that I know of (though some friends of mine might disagree). So do you mean if I can keep my finger in focus when it's held 5 or 6 inches in front of me, then, in theory, I should be able to see stereographs such as this? If so, the good news is that I can focus my finger just fine. So, I guess I'll just keep trying to see these stereo images.

Close, but not quite. The amount of crossing is consistent with looking at an object a few inches in front of your eyes. But you're focusing on something that's another foot or so behind that. That's the trick. Normally, your eye position and eye focus are tied together without you needing to think about it. Aim your eyes at something six inches away, and they will focus for a distance of six inches. Here you're aiming for six inches but focusing for eighteen. That is something under voluntary control, but it can take a bit of practice to figure it out.

So, focus on something eighteen inches away but then shift your gaze to this stereogram 6 inches away? PS - I have no problem seeing those "magic eye" images. Are the viewing/focusing methods similar?

The magic eye images work by having your eyes more parallel, not crossing. But otherwise it's the same principle- you're feeding a slightly different image to each eye.

A couple of things to try. From 18 or 20 inches away from the screen, look at the black space between the planet images. Then, slowly cross your eyes, not paying too much attention to what the image is actually doing. You should notice that the images of Mars are doing weird things, maybe becoming three, maybe overlapping in odd ways. But don't shift your focus to them, just play with controlling how your eyes are crossed. When they're at the right amount, there will be a stereo version of Mars, and your brain might do what it's supposed to do and "snap" onto it, the same sort of effect the magic eye images produce.

Another option. Again from 18 or 20 inches back, put your finger right between the two images. Then slowly bring your finger towards your eyes, keeping it in focus. You're looking at your finger, not the image. As you move your finger closer, you should notice the background image splitting into three, and when your finger is around 4-6 inches from your face you should have three equally spaced images. Try moving your finger left and right a little to cover each of them separately (but stay focused on your finger, not the background). Put your finger over the middle one, and then slowly drop it downwards so it's out of the way. Maybe the middle one will snap into focus in full 3D.

[Fred the Cat]

I too struggle to see this effect so I hope Chris's technique will help. But Mars will be disappearing later this week right before your eyes.

Take a peek.

[johnnydeep]

Close, but not quite. The amount of crossing is consistent with looking at an object a few inches in front of your eyes. But you're focusing on something that's another foot or so behind that. That's the trick. Normally, your eye position and eye focus are tied together without you needing to think about it. Aim your eyes at something six inches away, and they will focus for a distance of six inches. Here you're aiming for six inches but focusing for eighteen. That is something under voluntary control, but it can take a bit of practice to figure it out.

So, focus on something eighteen inches away but then shift your gaze to this stereogram 6 inches away? PS - I have no problem seeing those "magic eye" images. Are the viewing/focusing methods similar?

The magic eye images work by having your eyes more parallel, not crossing. But otherwise it's the same principle- you're feeding a slightly different image to each eye.

A couple of things to try. From 18 or 20 inches away from the screen, look at the black space between the planet images. Then, slowly cross your eyes, not paying too much attention to what the image is actually doing. You should notice that the images of Mars are doing weird things, maybe becoming three, maybe overlapping in odd ways. But don't shift your focus to them, just play with controlling how your eyes are crossed. When they're at the right amount, there will be a stereo version of Mars, and your brain might do what it's supposed to do and "snap" onto it, the same sort of effect the magic eye images produce.

Another option. Again from 18 or 20 inches back, put your finger right between the two images. Then slowly bring your finger towards your eyes, keeping it in focus. You're looking at your finger, not the image. As you move your finger closer, you should notice the background image splitting into three, and when your finger is around 4-6 inches from your face you should have three equally spaced images. Try moving your finger left and right a little to cover each of them separately (but stay focused on your finger, not the background). Put your finger over the middle one, and then slowly drop it downwards so it's out of the way. Maybe the middle one will snap into focus in full 3D.

Wow - your second method worked straight away and perfectly! At long last I can finally see these things! The middle of the three images is in 3D and the other two are still off to either side but blurry. Thanks a million Chris! (Though now I have a slight headache for my trouble )