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View Full Version : Pie in the sky? Do you see it? Is it in your eye?



2002-Jan-09, 08:57 AM
Having had a few years to ponder as gazing at the blobs of trees nestled on the muttled horizon through my lounge telescope ( not much distortion at 1 / 1 ). The one question which ponderance turned to aggrevation is what the !!!??? are the little dots and wavy things which glow opaquly as they slip slide ( from side to side ) and occasionly form sin waves of ... glowing... lucidness...

You know, the things your big sis or Dad said were 'floaties' when you asked her/him 'what are the things which float in the sky but follw me into my bedroom and live around the lamp at night time'?

Well, rather than think of an answer, please consider some previous observations made of these 'floaties', check out the next blue sky
and post your own.

1. Floaties are lucid shades of grey.

2. I count 2 main types of floaties.
'round' ones and 'wavy' ones.

Round floaties appear to be dark grey on thier circumference and light grey in the middle. Referenced to a bird on my neigbours fence, a round one is about the same size as tweeties head.

Wavy ones are sinusoids which usually look ( to me ) pretty much perfect. But occasionly display a few side bands.

The average amplitude of a wavy is ( approximatly )five 'tweeties on the fence'.

2. They are probably residing in the eyes
fluid center because their image changes position when you move your eyes, but stays stationary when you pan your head without moving your eyes. ( occasionly wavy ones do move if you are holding eyes and head still )

OK enough observations please post an explanation.

Before looking skyward, open your mind and consider this, Why do the wavy ones keep thier shape when I change velocity, why do stationary wavy ones always present there sinusoid on a horozontal axis, when moveing why do wavy ones move at constant vector, when moving why do wavy ones presenet their sinusoid on a axis superimposed on it's flight path.

Im running out of years to answer these questions so please help.

First Guesses:

A round one is a group of particles which are somehow bonded.

Both types maby in tension with.. .. ..not a suface....

Maby they emmit there greyness after stimuli from the big round yellow thing on the horizon.

As they accelerate etc when you move your eye, they have mass.

They conduct do not block photons from the horizon.

They have been magnified, possibly greatly.

Thanks for looking.

Code Red
2002-Jan-09, 09:36 AM
I remember reading an article about them a while back which gave them their name (I'll try and remember where I found it)... anyway, they're bits of stuff floating in your eyeball fluid. Nice.

Chief Engineer Scott
2002-Jan-09, 11:44 AM
If memory serves me correctly, constant "floaties" can be a sign of health problems.

GrapesOfWrath
2002-Jan-09, 12:30 PM
The Straight Dope: What are those threads that float in your field of vision? (http://www.straightdope.com/classics/a2_311.html) They're called "muscae volitantes."

John Kierein
2002-Jan-09, 01:40 PM
I suddenly developed floaters first in one eye and then in the other. Lots of 'em. They were the result of what the eye doc called a PVD or posterior vitreol detachment. They were accompanied at first by some light flashes in the peripheral vision. After a year the first one has faded quite a bit, but the second one which is about two months old is still bothersome. In my case I was told it was blood floating in the fluid in the eye. It is very easily seen against a nice blue sky. If you get this suddenly, you have to be careful that you don't get a retinal detachment which can cause blindness! Retinal detachment is irreversible if it isn't caught in time. Since the optics of your eye invert the image, you must look for a black curtain falling across your vision; if its from the top down then stand up because the retina is detaching at the bottom, and if it's from the bottom up then lie down because it's detaching from the top; then get emergency retinal surgery ASAP.

Code Red
2002-Jan-09, 02:11 PM
They're called "muscae volitantes."


A fine Australian vintage, as I recall... "Earthy, with hints of Oogleberries" (Posh Grub, March 2001)

Code Red
2002-Jan-09, 02:14 PM
On 2002-01-09 08:40, John Kierein wrote:
I suddenly developed floaters first in one eye and then in the other. Lots of 'em. They were the result of what the eye doc called a PVD or posterior vitreol detachment. They were accompanied at first by some light flashes in the peripheral vision. After a year the first one has faded quite a bit, but the second one which is about two months old is still bothersome. In my case I was told it was blood floating in the fluid in the eye. It is very easily seen against a nice blue sky. If you get this suddenly, you have to be careful that you don't get a retinal detachment which can cause blindness! Retinal detachment is irreversible if it isn't caught in time. Since the optics of your eye invert the image, you must look for a black curtain falling across your vision; if its from the top down then stand up because the retina is detaching at the bottom, and if it's from the bottom up then lie down because it's detaching from the top; then get emergency retinal surgery ASAP.


I had a similar problem about five years ago - I woke up one morning with limited vision in my right eye - it wasn't a detached retina, but a huge swath of the optic nerve had died, which is irreversible. I now have only a narrow band of vision on the inner field of my right eye. The good news is that this is really clear, which is handy when using the old scope.

Every cloud.... etc etc.......

2002-Jan-09, 03:33 PM
OK so the doctors above 'believe' floaties are bits of your feotus stuck in your eye. This could be true if there is a beam of Ultra sound or some other mechanical stimuli in our heads which would force these solids to act like a sine wave, as most wavy floties do.

I dont think so.
1.Round floaties are all the same size. The probability of ten ( least thousands )of long dead pieces of artery would be the same size is slim or effectivly 0.

2. Assume your eye is at rest relative to Earth .
The wavy floaty which moves through your vision does so in one direction. You see a sine wave faded at each end, move in the exact plain of it's x axis ( like a slightly off triggered oscilliscope trace of a sinusoid ). There is always a downward component in their velocity . Further more their Velocity is constant from the time they enter your field of view to the time they leave.... ( like they passed 'through' your eye ) ...not likely behaviour for a floatie when they are stuck in a viscous liquid which is at rest ( or swirling gently around ).

To me this rules out floaties as being comprised of bits of gunk which are dead.
If the doctors said tomorrow they were 'Active' living groups of cells I would be excited, But thats not going to happen.
Think a bit harder and have a good look at your floaties next sunny day.

To see a moving wavy, best to keep your eyes steady on the horizon, dont focus on a point, and hardest of all dont try to look at ( focus ) on the wavy as it wriggles by .
An old but good astronermers technique eh?

PS Not being a big head but my eyesight is over 20/20 ( honestly ) and I am certain of my observations, or whatever is taking place on my retina. If you where glasses, ask your friend who doesnt to look for you, cause I can only just see them.

GrapesOfWrath
2002-Jan-09, 04:09 PM
On 2002-01-09 10:33, RPN wrote:
If the doctors said tomorrow they were 'Active' living groups of cells I would be excited, But thats not going to happen.

Actually, that Straight Dope article I linked said that some opthamology texts describe instances of "intraocular parasites," so it has happened, but the condition seems to be rare.

<font size=-1>[Fixed quotation]</font>

<font size=-1>[ This Message was edited by: GrapesOfWrath on 2002-01-09 11:09 ]</font>

ToSeek
2002-Jan-09, 04:23 PM
On 2002-01-09 11:09, GrapesOfWrath wrote:
Actually, that Straight Dope article I linked said that some opthamology texts describe instances of "intraocular parasites," so it has happened, but the condition seems to be rare.


Things I don't need to read about while I'm sitting here eating my sandwich. /phpBB/images/smiles/icon_razz.gif

J-Man
2002-Jan-09, 09:29 PM
RPN said:
"
1.Round floaties are all the same size. The probability of ten ( least thousands )of long dead pieces of artery would be the same size is slim or effectivly 0.

2. Assume your eye is at rest relative to Earth .
The wavy floaty which moves through your vision does so in one direction. You see a sine wave faded at each end, move in the exact plain of it's x axis ( like a slightly off triggered oscilliscope trace of a sinusoid ). There is always a downward component in their velocity . Further more their Velocity is constant from the time they enter your field of view to the time they leave.... ( like they passed 'through' your eye ) ...not likely behaviour for a floatie when they are stuck in a viscous liquid which is at rest ( or swirling gently around ).
"

J-man says:
I don't want to be a party pooper, but I have 2 concerns...
1) How did you measure that all the "round ones" are the same size? Or did you mean similar size?

2) I think you have generalized the patterns of the "wavey ones". I can testify that I have learned (prior to age 12) to make the "wavey ones" move in other directions and speed. It's simply a matter of changing your focus/eye pressure. I believe anyone can learn this, but I don't recommend it as it probably can cause damage.

DStahl
2002-Jan-10, 01:46 AM
Tiny bits of lint and dust on a microscope slide, viewed with the 'scope out of focus or maladjusted, look a lot like my own personal floaties. That leads me to think that the consistencies in shape and form--like the small circular shapes--are optical effects that don't reflect (or refract?) the actual shape of the intra-ocular oddity.

Could be dead wrong, though. Has anybody else tried viewing interference fringes through your eyelashes?

[Later: Oops, that would probably be "diffraction fringes." Sorry.]

--Don

<font size=-1>[ This Message was edited by: DStahl on 2002-01-13 20:17 ]</font>

J-Man
2002-Jan-16, 08:13 PM
DStahl said: "
Could be dead wrong, though. Has anybody else tried viewing interference fringes through your eyelashes?
"

Yup, that kept me occupied for a while as a child... especilly when looking toward street lamps or other light sources... I'm amazed I can still see as well as I can.