Stereo Distance Perception

I=20have=20always=20been=20fascinated=20by=20the=2 0phenomenon=20of=
=20depth=20perception=20in=20vision.=20It=20would= 20seem=20that=20=
this=20is=20a=20combination=20of=20two=20mechanism s=20:

First=20there=20is=20the=20automatic=20simple=20fo cus=20position=
=20of=20the=20eye=20to=20achieve=20a=20clear=20ima ge.=20This=20doe=
sn't=20depend=20on=20using=20both=20eyes=20and=20w ill=20work=20jus=
t=20as=20well=20with=20one=20eye.

Then,=20there=20is=20the=20slight=20though=20very= 20significant=20=
difference=20between=20the=20perceived=20images=20 in=20the=20left=
=20and=20right=20eyes,=20owing=20to=20the=20differ ence=20in=20hori=
zontal=20positions=20of=20the=20eyes.=20This=20is= 20much=20greater=
=20at=20closer=20image=20distances=20and=20dependa nt=20on=20using=
=20both=20eyes.=20It=20is=20my=20perception=20(=20 no=20pun=20inten=
ded=20),=20that=20at=20all=20close=20or=20reasonab ly=20limited=20d=
istances,=20this=20is=20the=20greater=20part=20of= 20depth=20percep=
tion.

Images,=20Stereo=201,=20-2=20and=20-3=20have=20been=20developed=20=
to=20test=20this=20second=20mechanism.=20See=20:=2 0https://postimg=
=2Ecc/gallery/3fnjbwcn4/

These=20depend=20on=20deliberately=20misaligning=2 0eyes=20in=20suc=
h=20a=20way=20that=20the=20two=20orange=20dots=20a t=20the=20top=20=
of=20the=20image=20are=20spilt=20and=20resolved=20 into=20three=20i=
mages.

With=20an=20image=20displayed=20full=20screen,=20s tare=20above=20t=
he=20screen=20as=20to=20something=20more=20distant ,=20which=20will=
=20shift=20the=20left=20image=20to=20the=20right=2 0and=20the=20rig=
ht=20image=20to=20the=20left.=20When=20the=20image s=20resolve=20to=
=20three,=20by=20overlapping=20of=20the=20right=20 dot=20of=20the=
=20left=20eye=20with=20the=20left=20dot=20of=20the =20right=20eye,=
=20the=20eyes=20are=20set=20to=20perceive=20depth= 20in=20the=20ima=
ge.

Each=20image=20consists=20of=20a=20narrow=20random =20display=20of=
=20dots=20extending=20top=20to=20bottom,=20where=2 0this=20displaye=
d=20area=20is=20repeated=20horizontally=20across=2 0the=20image=20w=
idth,=20with=20the=20same=20approximate=20spacing= 20as=20between=
=20the=20three=20orange=20dots.=20The=20eyes=20wil l=20lock=20on=20=
the=20display=20where=20each=20eye=20is=20actually =20locked=20on=
=20subsequent=20repeats=20of=20the=20display.=20No w,=20the=20displ=
ay=20has=20deliberately=20been=20altered=20in=20th e=20horizontal=
=20direction=20at=20various=20areas=20of=20the=20w hole=20image,=20=
such=20that=20the=20eyes=20will=20perceive=20an=20 apparent=20shift=
=20in=20angular=20position=20of=20these=20areas,=2 0which=20will=20=
be=20perceived=20as=20a=20different=20depth=20via= 20the=20second=
=20mechanism.=20A=20very=20neat=20trick=20that=20w orks=20surprisin=
gly=20well=20!

In article ,
says...
I=20have=20always=20been=20fascinated=20by=20the=2 0phenomenon=20of=
=20depth=20perception=20in=20vision.=20It=20would= 20seem=20that=20=
this=20is=20a=20combination=20of=20two=20mechanism s=20:

I'm getting this very hard to read stuff. What did you use to
post this message?
--
Alfred Molon

Olympus 4/3 and micro 4/3 cameras forum at
https://groups.io/g/myolympus
https://myolympus.org/ photo sharing site

On Sun, 7 Feb 2021 13:00:01 +0100, Alfred Molon
wrote:

In article ,
says...
I=20have=20always=20been=20fascinated=20by=20the=2 0phenomenon=20of=
=20depth=20perception=20in=20vision.=20It=20would= 20seem=20that=20=
this=20is=20a=20combination=20of=20two=20mechanism s=20:

I'm getting this very hard to read stuff. What did you use to
post this message?

It reads perfectly fine here using Agent.

Making the question: What are you reading it with?

On Feb 7, 2021, wrote
(in ):

On Sun, 7 Feb 2021 13:00:01 +0100, Alfred Molon
wrote:

In ,
says...
I=20have=20always=20been=20fascinated=20by=20the=2 0phenomenon=20of=
=20depth=20perception=20in=20vision.=20It=20would= 20seem=20that=20=
this=20is=20a=20combination=20of=20two=20mechanism s=20:

I'm getting this very hard to read stuff. What did you use to
post this message?

It reads perfectly fine here using Agent.

Making the question: What are you reading it with?

I believe that Alfred is referring to your three images not the text. So the Usenet client used is irrelevant.

The three images are for me an unviewable mess.

--
Regards,
Savageduck

On Sun, 07 Feb 2021 06:23:12 -0800, Savageduck
wrote:

I believe that Alfred is referring to your three images not the text. So the Usenet client used is irrelevant.

Ah, my mistake.

The three images are for me an unviewable mess.

No, they are stereo images, and work for me.

You need to focus solidly on the two red dots at the top.

Gradually a third dot will appear between them, at which point the
stereo effect kicks in.

These are traditional examples used to demonstrate the stereo effect,.
if I remember correctly.

On Feb 7, 2021, wrote
(in ):

On Sun, 07 Feb 2021 06:23:12 -0800, Savageduck
wrote:

I believe that Alfred is referring to your three images not the text. So the Usenet client used is irrelevant.

Ah, my mistake.

The three images are for me an unviewable mess.

No, they are stereo images, and work for me.

You need to focus solidly on the two red dots at the top.

Gradually a third dot will appear between them, at which point the
stereo effect kicks in.

These are traditional examples used to demonstrate the stereo effect,.
if I remember correctly.

OK! However, while others might be, personally I am not particularly interested in this type of stereo vision trickery.

--
Regards,
Savageduck

Not=20sure=20what=20all=20the=20fuss=20is=20about. =20When=20I=20en=
ter=20https://postimg.cc/gallery/3fnjbwcn4/
in=20Internet=20browser,=20the=203=20images=20come =20up=20with=20n=
o=20problem.=20Be=20happy=20to=20send=20as=20E-mail=20attachments=
=20within=20reason.

=20
=20=20These=20are=20traditional=20examples=20use d=20to=20demonst=
rate=20the=20stereo=20effect,.
=20=20if=20I=20remember=20correctly.

=20OK!=20However,=20while=20others=20might=20be,= 20personally=20I=
=20am=20not=20particularly=20interested=20in=20thi s=20type=20of=20=
stereo=20vision=20trickery.



It=20is=20just=20a=20point=20of=20interest,=20and= 20it=20IS=20an=
=20important=20part=20of=20depth=20perception=20at =20close=20dista=
nces=20IMHO.

On 2/6/2021 6:31 PM, wrote:
I have always been fascinated by the phenomenon of depth perception
in vision. It would seem that this is a combination of two mechanisms
:

First there is the automatic simple focus position of the eye to
achieve a clear image. This doesn't depend on using both eyes and
will work just as well with one eye.

Then, there is the slight though very significant difference between
the perceived images in the left and right eyes, owing to the
difference in horizontal positions of the eyes. This is much greater
at closer image distances and dependant on using both eyes. It is my
perception ( no pun intended ), that at all close or reasonably
limited distances, this is the greater part of depth perception.

Images, Stereo 1, -2 and -3 have been developed to test this second
mechanism. See : https://postimg.cc/gallery/3fnjbwcn4/

These depend on deliberately misaligning eyes in such a way that the
two orange dots at the top of the image are spilt and resolved into
three images.

With an image displayed full screen, stare above the screen as to
something more distant, which will shift the left image to the right
and the right image to the left. When the images resolve to three, by
overlapping of the right dot of the left eye with the left dot of the
right eye, the eyes are set to perceive depth in the image.

Each image consists of a narrow random display of dots extending top
to bottom, where this displayed area is repeated horizontally across
the image width, with the same approximate spacing as between the
three orange dots. The eyes will lock on the display where each eye
is actually locked on subsequent repeats of the display. Now, the
display has deliberately been altered in the horizontal direction at
various areas of the whole image, such that the eyes will perceive an
apparent shift in angular position of these areas, which will be
perceived as a different depth via the second mechanism. A very neat
trick that works surprisingly well !


Have you looked into the work of Bela Julesz?
Seems he discovered this phenomena while
working on visualization of random pattern generators.
He did a lot of work in the field of visual perception.
--
==
Later...
Ron C
--

In article , Alfred
Molon wrote:

In article ,
says...
I=20have=20always=20been=20fascinated=20by=20the=2 0phenomenon=20of=
=20depth=20perception=20in=20vision.=20It=20would= 20seem=20that=20=
this=20is=20a=20combination=20of=20two=20mechanism s=20:

I'm getting this very hard to read stuff. What did you use to
post this message?

the problem is your newsreader.