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Lance1234
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Lunar halucinations
      #6102668 - 09/26/13 04:47 PM

Maybe I'm finally losing it. I was looking at the moon night before last using a medium power eyepiece and everything would look normal then all of a sudden all of the craters in the fully lit areas would invert and look like raised mounds! The only way I could get them back to being craters was to look at a clearly defined crater on the terminator, at which point they would pop back into being craters. Then I'd go back to looking at some feature and, wham, they'd turn back into mounds again. This just kept happening and was a real annoyance. Anyone else ever experisnced this? The only thing different than when I've observed the moon before was that this is the first time I can recall observinga waning moon, but whether that could have any impact I have no idea. While it was an amusing optical illusion, it played havoc with trying to do any serious observation.

Lance


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GlennLeDrew
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Re: Lunar halucinations new [Re: Lance1234]
      #6102774 - 09/26/13 06:05 PM

This is a well known illusion. It's more likely when the true field is small, and all visible craters have a similar degree of shadowing. With wider fields, thus covering a larger area in which crater shadows have a widely varying aspect, this illusion is much less likely to insinuate itself into your brain.

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cpsTN
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Re: Lunar halucinations new [Re: GlennLeDrew]
      #6103170 - 09/26/13 10:34 PM

I have seen this too and has to do with contrast. Sometimes, I see globes like that. I see the flowing shapes of the oceans and the shapes of continents black out.

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Qwickdraw
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Re: Lunar halucinations new [Re: cpsTN]
      #6115844 - 10/03/13 06:40 PM

Now if you started telling us it was turning orange and you saw nice eating it we would be worried.

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Asbytec
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Re: Lunar halucinations new [Re: GlennLeDrew]
      #6133222 - 10/12/13 02:48 PM

Quote:

This is a well known illusion...this illusion is much less likely to insinuate itself into your brain.



Glenn is correct. Unfortunately, though, it means you're quite sane. Schizophrenics are not fooled by the hollow mask illusion. I hope to observe it sometime soon.


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dce21b
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Re: Lunar halucinations new [Re: Asbytec]
      #6138172 - 10/15/13 12:23 AM

Shroomy

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azure1961p
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Re: Lunar halucinations new [Re: Asbytec]
      #6138583 - 10/15/13 09:03 AM

Quote:

Quote:

This is a well known illusion...this illusion is much less likely to insinuate itself into your brain.



Glenn is correct. Unfortunately, though, it means you're quite sane. Schizophrenics are not fooled by the hollow mask illusion. I hope to observe it sometime soon.




Very true with schizophrenics not having this illusion but then it made me wonder - why not? I mean what if the world was such that this reverse relief effect was actually the way the moon really is - then how this be seen by these individuals? Its a 50/50 flip of the switch to see it this way - and even though we know the right way it should look - if a duplicate moon came along in the same orbit with all relief reversed - would the schizophrenics still see the moon unfooled to its true nature or see it for its false nature? If so how and why - where's the truth coming from?

Pete

Edited by azure1961p (10/15/13 09:06 AM)


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Chuck Hards
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Re: Lunar halucinations new [Re: azure1961p]
      #6138752 - 10/15/13 10:42 AM

I remember years ago looking at stereo pairs from aerial surveys. When the pairs were reversed left-for-right, the same effect happened. River beds were suddenly raised features, mountains became depressions. But that was a two-eyed phenomenon. I'm assuming Lance wasn't using a bino viewer since he wrote "eyepiece", singular.

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Asbytec
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Re: Lunar halucinations new [Re: Chuck Hards]
      #6139892 - 10/15/13 10:00 PM

I can't remember having seen this illusion. Does one really need two eyes to make it happen, or at least happen more easily?

Pete, it's curious schizophrenics have a better grip on the "truth" than we do. Kind of scary.


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ETXer
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Re: Lunar halucinations new [Re: Asbytec]
      #6163622 - 10/28/13 11:09 PM

I remember having the same experience when looking at photos of the Moon taken from the Apollo spacecraft in lunar orbit. I was around 10 years old and I couldn't understand why I was seeing mounds when everyone else saw craters; I had to really concentrate to make them appear correct!

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Steve OK
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Re: Lunar halucinations new [Re: ETXer]
      #6186215 - 11/10/13 10:09 AM Attachment (16 downloads)

This illusion may also have to do with the direction, or perceived direction, of the lighting. Our brains are "trained" to see objects lit from above, as most often happens in nature. When a lunar landscape is lit from "below" in our field of view, and our brains assume the light is coming from above, craters become domes.

Steve


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Michael Rapp
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Re: Lunar halucinations new [Re: Steve OK]
      #6188189 - 11/11/13 09:07 AM

I've had this happen and it is eerie. You recognize what has happened, but it takes some effort to shake it.

Although, pretty cool to have an entire world invert itself before your eyes.


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Asbytec
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Re: Lunar halucinations new [Re: Steve OK]
      #6190034 - 11/12/13 06:13 AM

I'm getting worried, those images still don't fool me and they should. Maybe I'm skitzo.

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Ed D
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Re: Lunar halucinations new [Re: Asbytec]
      #6190139 - 11/12/13 08:34 AM

Last night I was observing the moon, comparing performance of several eyepieces and barlows. I thought it interesting that it was when I used eyepieces of one particular design and focal length the effect kicked in - pretty much as Glenn explained. At least I know I'm not skitzo.

Ed D

Edited by Ed D (11/12/13 08:50 AM)


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Fred Garvin
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Re: Lunar halucinations new [Re: Ed D]
      #6210007 - 11/22/13 06:27 PM

LOL...I'm so glad I saw this post. I just got my NexStar 8SE and due to the new scope curse have only had a couple clear nights, both with 3/4 moon....my previous scopes came nowhere near the detail the 8SE provides....

Toward the end of my last session, the craters suddenly became mounds. At first I couldn't figure out what I was looking at. I consulted my moon maps, and no "mounds"....but....but....I'm seeing mounds......then I realized it must be an illusion so backed off my 9mm to the 25mm and saw craters again....put the 9mm back in and it didn't take long for the mounds to come back....


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