Difficult technical question on ISO & light

[Guest]

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Colin D wrote:

>
> BillyJoeJimBob wrote:
>
>
>>Tom Phillips wrote:
>>
>>>Quote: "the pixel size of a highly sensitive emulsion layer is
>>>assumed to be 100 square micrometers on the basis of the fact
>>>that a color film with an ISO 400 sensitivity and 135 format
>>>contains 24 million pixels."
>>
>>Typical 135 format film measures 36x24 mm, for a total imaging area
>>of 864 square mm, or 864,000,000 square microns. Dividing this by
>>the quoted pixel size above yields 8,640,000 "pixels" on the 135
>>format film. I have no idea how the authors of that quote came up
>>with 24 million, which at first glance appears to be too large by
>>nearly a factor of three. Perhaps the authors assume some degree of
>>overlap between "pixels" on the emulsion layer?
>>
>>BJJB
>
>
> Because with 8-bit depth, it takes 24 bits, or three bytes per pixel,
> not one as you assume in your calculations.

My calculations have nothing at all to do with bytes, nor does the
original quoted text. We're talking "pixels", as in "spatially
separated discrete imaging sensor elements". The authors of the
original quote did not state anything regarding "24 million bytes"
of data contained in 135 format film. I made no statement regarding
8 million bytes of data.

In the context of the original quote, bytes are irrelevant.

Even if we were to consider the possibility that the authors were
speaking of RGB color, the term "emulsion layer" implies a single
layer (i.e. a single color channel), not three. There's no "three"
to multiply by in a single emulsion layer.

BJJB

 

[Guest]

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A pixel is not a bit. A pixel is a graphical dot consisting of 3D or 4D
information. While the physical placement is only 2D he third dimension is
resolution of colour.

If a pixel was one bit then it can only contain two colours, being
represented by on and off.

For decent photographic representation a pixel would be represented by 24 or
32 bits of information. 32 bit pixels sometimes are 4D, with the fourth
dimension being transparency.

Bits and bytes are not involved in this thread previously. Only pixels vs.
grain of film. How we represent a pixel is another matter.

<JPS@no.komm> wrote in message
news:do77o0psfp2khsurcmvn9va4as6j48ende@4ax.com...
> In message <41836510.C6138E4B@killspam.127.0.0.1>,
> Colin D <ColinD@killspam.127.0.0.1> wrote:
>
> >Because with 8-bit depth, it takes 24 bits, or three bytes per pixel,
> >not one as you assume in your calculations.
>
> A "pixel" is a 2-D spatial unit. As far as depth is concerned, all you
> need for a pixel is two states (one bit, if digital).
> --
>
> <>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
> John P Sheehy <JPS@no.komm>
> ><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><

 

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"BillyJoeJimBob" <bjjb@nowhere.antispam.com> wrote in message
news😛ZCdnThVxcHSIh7cRVn-sQ@rcn.net...
> [...]
> Even if we were to consider the possibility that the authors were
> speaking of RGB color, the term "emulsion layer" implies a single
> layer (i.e. a single color channel), not three. There's no "three"
> to multiply by in a single emulsion layer.

NB: Modern B&W film emulsions are made up of more than one layer, so there
is a multiplier.

 

[Guest]

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In message <C8mdnXh_D6FmOh7cRVn-sw@golden.net>,
"Gymmy Bob" <nospamming@bite.me> wrote:

>A pixel is not a bit.

I didn't say it was. Where did you learn to read? They failed you.

>A pixel is a graphical dot consisting of 3D or 4D
>information. While the physical placement is only 2D he third dimension is
>resolution of colour.

.... of one pixel.

>If a pixel was one bit then it can only contain two colours, being
>represented by on and off.

Sometimes, that's how a pixel is.

>For decent photographic representation a pixel would be represented by 24 or
>32 bits of information. 32 bit pixels sometimes are 4D, with the fourth
>dimension being transparency.

.... of one pixel.

>Bits and bytes are not involved in this thread previously. Only pixels vs.
>grain of film. How we represent a pixel is another matter.

No, I replied to someone who implied that the R, G, and B of the same
2-D location of film are three separate pixels.


--

<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><

 

[Guest]

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In message <AeydnSC6OIt_JR7cRVn-3g@golden.net>,
"Gymmy Bob" <nospamming@bite.me> wrote:

>You just disagree with something but not sure what it is?
>Are you over 12 years old? Having a bad day?

Are you one of those people that see themselves reflected in others?
--

<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><

 

[john]

Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital,rec.photo.equipment.35mm,rec.photo.film+labs,rec.photo.darkroom (More info?)

On Sat, 30 Oct 2004 16:01:30 GMT, JPS@no.komm wrote:

>Are you one of those people that see themselves reflected in others?

Personally I do give people the benefit of a doubt. I tend to
believe that all people are good and intelligent until they prove
otherwise.


Regards,

John S. Douglas, Photographer - http://www.puresilver.org
Vote "No! for the status quo. Vote 3rd party !!

 

[Guest]

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In message <lvl7o09qjq7lv209nic051jph36p95d4ca@4ax.com>,
John <use_net@puresilver.org> wrote:

>On Sat, 30 Oct 2004 16:01:30 GMT, JPS@no.komm wrote:
>
>>Are you one of those people that see themselves reflected in others?
>
> Personally I do give people the benefit of a doubt. I tend to
>believe that all people are good and intelligent until they prove
>otherwise.

I wasn't taking a survey. I asked an individual a question in the
context of his statement.

Everything he said about me applied very well to himself; that's why I
posed the question.
--

<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<>
John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>><

 

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Tom Phillips wrote:

> Chris Brown wrote:
> >
> > In article <41823255.BC08FE81@aol.com>,
> > Tom Phillips <nospam777@aol.com> wrote:
> > >
> > >>
> > >> The medium format does give me superior image quality to both of them, and
> > >> it's dramatically superior. The relative difference between the digital and
> > >> 35mm, in comparison, is not worth bothering with. They're both adequate for
> > >> an A4 print, and ropey for an A3 print.
> > >
> > >Never shot Kodachrome 25 or 64, I gather...
> >
> > Usually Velvia 50, although I'm doing a lot more Provia 100F these days.
> >
> > >The questionn is, why is this even a debate?
> >
> > It's not - in the eyes of nearly everyone who regarded this as some kind of
> > "contest", 35mm "lost" years ago, with the previous genertion of DSLRs.
> > You're trotting out the sort of stuff that used to infest r.p.e.35mm and
> > r.p.d about 2-4 years ago. Pretty much everyone else has accepted reality
> > and moved on.
>
> Pixels are still limited by Nyquist. The garden variety
> consumer digital camera uses a bayer pattern, meaning color
> pixels are interpolated 4:1 to get one full color pixel.
> Thus the sensor reolution does not reflect the actual image
> pixel resolution. There's a long way to go before one
> shot consumer digital cameras can match even 35mm film.
> Now, it may look good in typical consumer prints, but to
> the human eye this only requires about 6mp to achieve.
> What I'm saying is the average 400 speed color film has
> more resolving ability than this available, even if it's
> not typically needed or used by the average consumer.
>
> > >For _pictorial_ imaging, film is the better medium. The
> > >facts bear this out.
> >
> > I quite agree, you just need the film to be 6cm wide or more to compete
> > in the quality stakes these days.
>
> Well, I shoot 4x5. Pixels will never be able to get that
> small or numerous to effectively compete there.
>
> > >Digital,imaging is not photographic. It does not produce
> > >a photograph.
> >
> > If you say so.
>
> It's not what anyone says, it's what the technology actually
> does and doesn't do. It produces data, which is why it's a
> _different_ imaging medium. Data is not an optical image nor
> a phototgraph. Thus while an imaging medium, it's not
> photographic.

There's less difference than you think. A negative or transparency contains data
just as much as a digital file, it just happens to be stored on a suitable medium
and in such a manner that the data is recognisable by the human eye. Digital data
simply requires a computer to rearrange the data so it too is recognisable by the
eye. How does the fact that data in a negative can be recognised by eye make it any
more or less 'photographic' than the same data stored in a file that takes a machine
to make it viewable? What about microfilm images, unreadable unless processed
(magnified) by a machine, are they 'photographic', since you can't read them without
intervention? And at the ultimate resolution, film is not only digital, but binary
- a grain is either black or non-existent. i.e. clear substrate, and the perceived
gradation is dependent on the amount of black grains to white space in a given area.

Colin

Colin.

 

[john]

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On Sat, 30 Oct 2004 23:10:20 +1300, Colin D
<ColinD@killspam.127.0.0.1> wrote:

>How does the fact that data in a negative can be recognised by eye make it any
>more or less 'photographic' than the same data stored in a file that takes a machine
>to make it viewable? What about microfilm images, unreadable unless processed
>(magnified) by a machine, are they 'photographic', since you can't read them without
>intervention?

Photography and image magnification is an analog process
wherein the image is created and developed in the medium.


Regards,

John S. Douglas, Photographer - http://www.puresilver.org
Vote "No! for the status quo. Vote 3rd party !!

 

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"John" <use_net@puresilver.org> wrote in message
news:j7b7o0hk49k11c04lhcf69p154i2n7nkd9@4ax.com...
> On Sat, 30 Oct 2004 17:05:36 +0900, Susan Perkins <deleted@> wrote:
>
>>>Digital sensors produce data.
>>
>>Yes, they produce data based on a light signature. That is to say, their
>>data
>>is completely, 100 percent, dependent on light for generation. Without
>>light,
>>no data. The result is clearly "light writing" (or photography) to anyone
>>except those who would argue about how many angels can dance on the head
>>of a
>>pin.
>
> Nope. The human eye is an analog mechanism. Photography is an
> effort to capture what the eyes can see in a relatively permanent
> medium. Digital is an effort to make money. Digital images are not
> analog nor are they permanent. It follows that digital is NOT
> photography.

The only difference between digital planes and film is that the "pixels" on
film are randomly placed in the sensing plane, and not placed in regular
defined positions as they are in a CCD plane. Otherwise, the film is just as
digital as the CCD plane. As a matter of fact, on some small enough level,
the whole universe is digital.

 

[Guest]

Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital,rec.photo.equipment.35mm,rec.photo.film+labs,rec.photo.darkroom (More info?)

Well said!

It depends how much resolution you want to dig in to. Analogue is just
digital with blur.



"William Graham" <weg9@comcast.net> wrote in message
news:QdVgd.443860$mD.338477@attbi_s02...
>

>
> The only difference between digital planes and film is that the "pixels"
on
> film are randomly placed in the sensing plane, and not placed in regular
> defined positions as they are in a CCD plane. Otherwise, the film is just
as
> digital as the CCD plane. As a matter of fact, on some small enough level,
> the whole universe is digital.
>
>

 

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"Gymmy Bob" <nospamming@bite.me> wrote in message
news:g--dnaKE__IW0BncRVn-tQ@golden.net...
> Well said!
>
> It depends how much resolution you want to dig in to. Analogue is just
> digital with blur.

Digital is digital. Period. You are just so confused.

 

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"Gymmy Bob" <nospamming@bite.me> wrote in message
news:ZsKdnfIad9tWJB7cRVn-jA@golden.net...
> The human eye is not an analogue device. The resolution is estimated at
> around 1000 x 1000 pixels of resolution but the rapid eye movements allow
> the brain to construct images of much higher resolution by interpolating
> over time with repeated scans.

The rods and cones of the retina constitute a digital sensing plane, and the
brains interpretation of the scans (as you mention above) is the, "software"
that produces the final image.

 

[Guest]

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"William Graham" <weg9@comcast.net> wrote in message
news:fiVgd.335836$3l3.5745@attbi_s03...
> The rods and cones of the retina constitute a digital sensing plane, and
> the brains interpretation of the scans (as you mention above) is the,
> "software" that produces the final image.

Most of the processing we are concerned with is in the retina. The brain
couples to recognition of those signals, not interpretation of them.

 

[Guest]

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Tom Phillips wrote:

> Ken Alverson wrote:
> >
> > "Tom Phillips" <nospam777@aol.com> wrote in message
> > news:4182AD9B.B7007F9A@aol.com...
> > >
> > > Ken Alverson wrote:
> > >>
> > >> "Tom Phillips" <nospam777@aol.com> wrote in message
> > >> news:41823255.BC08FE81@aol.com...
> > >> >
> > >> > Photography produces a photograph. And a photograph is an
> > >> > image written on photosensitive materials by the direct
> > >> > action of light. Digital imaging is electronic and about
> > >> > as "photographic" as your television cameraman broadcasting
> > >> > to your T.V. set. Again, no photograph.
> > >>
> > >> Photograph, from the greek "photo-" meaning light and "-graph" meaning
> > >> recording. Whether the recording was made photochemically and stored on
> > >> physical media or photoelectrically and stored on digital media is really
> > >> inconsequential to its status as a photograph.
> > >
> > > No. it means (literally) light writing, i.e., as in physically
> > > drawing with light.
> > >
> > > Digital sensors produce data.
> >
> > Write, draw, or record. All meaning to take something transient and make a
> > more permenant record of it.
> >
> > But let's say "-graph" was a strict literal translation to "writing". Are you
> > implying writers who use word processors aren't really writing?
>
> I'm stating a fact. Digital sensors do not create a
> photograph. They transmit a voltage, regenerated into

> <snip>

'A' voltage comes from 'a' pixel. A sensor produces several million voltages from
several million pixels, which when displayed properly produce a photograph. A
single grain does not produce a photograph either. Several million can. The
storage medium is irrelevant.

Colin

 

[Guest]

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In article <41836A8E.4404EBE1@killspam.127.0.0.1>,
Colin D <ColinD@killspam.127.0.0.1> wrote:

> The storage medium is irrelevant.

Oh really? Try storaging the the roughly 10,000 images, 35mm, 120
4x5, 8x10. I have on film at full digital equivalent resolution at the same
cost I have invested in their storage.
--
LF Website @ http://members.verizon.net/~gregoryblank

"To announce that there must be no criticism of the President,
or that we are to stand by the President, right or wrong,
is not only unpatriotic and servile, but is morally treasonable
to the American public."--Theodore Roosevelt, May 7, 1918

 

[john]

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On Sat, 30 Oct 2004 23:18:54 +1300, Colin D
<ColinD@killspam.127.0.0.1> wrote:

>'A' voltage comes from 'a' pixel. A sensor produces several million voltages from
>several million pixels, which when displayed properly produce a photograph.

No, it creates a digital image.

>A single grain does not produce a photograph either. Several million can.

Nope. It takes light. Usually light strikes a sensitized
emulsion, the emulsion is developed and then light is projected
through that emulsion to create a positive enlargement.

>The storage medium is irrelevant.

Nope. Photography was made possible by the medium. Once you
negate the medium you have negated the craft.


Regards,

John S. Douglas, Photographer - http://www.puresilver.org
Vote "No! for the status quo. Vote 3rd party !!

 

[john]

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On Sat, 30 Oct 2004 13:39:18 GMT, Gregory W Blank
<gblank@despamit.net> wrote:

>> The storage medium is irrelevant.
>
>Oh really? Try storaging the the roughly 10,000 images, 35mm, 120
>4x5, 8x10. I have on film at full digital equivalent resolution at the same
>cost I have invested in their storage.

And don't forget the backups !


Regards,

John S. Douglas, Photographer - http://www.puresilver.org
Vote "No! for the status quo. Vote 3rd party !!

 

[Guest]

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"Colin D" <ColinD@killspam.127.0.0.1> wrote in message
news:41842A7B.7AD50105@killspam.127.0.0.1...

> John wrote:
>
>> On Sat, 30 Oct 2004 23:18:54 +1300, Colin D
>> <ColinD@killspam.127.0.0.1> wrote:
>>
>> >'A' voltage comes from 'a' pixel. A sensor produces several million
>> >voltages from
>> >several million pixels, which when displayed properly produce a
>> >photograph.
>>
>> No, it creates a digital image.
>
> The image, chemical or digital, is created by the action of light - a
> 'light graph'.
> How can you deny that a digital image is created by light?

Nitpicking. Actually, the image comes from radiation, some of which the
eye cannot detect. There's a virtue there to be exploited. But I digress.

 

[Guest]

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Susan Perkins wrote:
>
> On Fri, 29 Oct 2004 16:03:49 GMT, in article
> <so5a52-m89.ln1@narcissus.dyndns.org>, Chris Brown
> <cpbrown@ntlworld.no_uce_please.com> wrote:
>
> >In article <41823255.BC08FE81@aol.com>,
> >Tom Phillips <nospam777@aol.com> wrote:
> >>
> >>>
> >>> The medium format does give me superior image quality to both of them, and
> >>> it's dramatically superior. The relative difference between the digital and
> >>> 35mm, in comparison, is not worth bothering with. They're both adequate for
> >>> an A4 print, and ropey for an A3 print.
> >>
> >>Never shot Kodachrome 25 or 64, I gather...
> >
> >Usually Velvia 50, although I'm doing a lot more Provia 100F these days.
> >
> >>The questionn is, why is this even a debate?
> >
> >It's not - in the eyes of nearly everyone who regarded this as some kind of
> >"contest", 35mm "lost" years ago, with the previous genertion of DSLRs.
> >You're trotting out the sort of stuff that used to infest r.p.e.35mm and
> >r.p.d about 2-4 years ago. Pretty much everyone else has accepted reality
> >and moved on.
> >
> >>For _pictorial_ imaging, film is the better medium. The
> >>facts bear this out.
> >
> >I quite agree, you just need the film to be 6cm wide or more to compete
> >in the quality stakes these days.
> >
> >>Digital,imaging is not photographic. It does not produce
> >>a photograph.
> >
> >If you say so.
>
> Photo = light
>
> Graph = write
>
> If digital photography isn't "light writing", every bit as much as film
> photography, we have a real mystery on our hands as to what exactly these
> digital appliances are really doing. <g>

No mystery at all. Digital is photoelectric. Like your solar panel...

The only mystery is why some moron crossposted this thread...

 

[Guest]

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Susan Perkins wrote:
>
> On Fri, 29 Oct 2004 14:33:08 -0600, in article <4182A902.A58F1699@aol.com>, Tom
> Phillips <nospam777@aol.com> wrote:
>
> >Well, I shoot 4x5. Pixels will never be able to get that
> >small or numerous to effectively compete there.
>
> Never. The man actually said "never" in a rather new technological
> environment. I'm glad I don't own stock in a company that he manages. <g>

Ah... let me know when the electronics that make silicon
sensitive enough to produce a voltage from electromagnectic
radiation can get as small as a silver haliode ***MOLECULE***.

never going to happen. Never...

You want to make a argument, better back it up with something
from _our_ universe of physcal laws...

 

[Guest]

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Tom Phillips wrote:

> Tom Phillips wrote:
> >
> > Chris Brown wrote:
> > >
> > > In article <4181C14A.D6ECD4FA@aol.com>,
> > > Tom Phillips <nospam777@aol.com> wrote:
> > > >
> > > >Film can be exposed for hours. Try that with a digital sensor.
> > > >It simply one of the differences between these two imaging
> > > >mediums.
> > >
> > > You really should avoid such pontifications unless you're absolutely certain
> > > you're correct, as you aren't in this case. Canon's current DSLRs, to take
> > > one example, manage perfectly hapilly with multi-hour exposures. The only
> > > major problem is that holding the shutter open that long may drain the
> > > battery.
> >
> > uh huh... multi-hour digital. And no noise due to heat. right.
> > (and heat is *inherent* in digital sensor exposure...)
> >
> > Show me a "multi hour" digital exposure.
>
> And I don't mean astrophotography.
>
> The ability of the canon EOS to do astrophotography is
> in part due to the employment of a larger pixel. Larger
> pixels mean a better signal and less noise, *but* (also
> less pixel resolution. So _pictorial_ resolution is
> sacrificed for better signal and less noise. This is hardly
> comparable with film, where resolution abilities is not
> based on large grain size, but _small_ grain size and where
> exposure and signal frequency is on a molecular level, not
> a pixel level.

What?? You've just blown what ever credibility you might have had. Of course
larger sensors have larger pixels - but for two cameras with different-sized
sensors, each with the same number of pixels, the pixel resolution is identical.
You are overlooking the fact that the larger sensor will also have a larger image
projected onto it, and (ignoring diffraction and noise effects) each will produce
the same sharpness of image. It is exactly analogous to using a fast film with
coarse grain and countering the grain with a larger format.

By the way, as far as film is concerned, exposure, i.e. photons hitting molecules,
might be on a molecular level, but signal frequency is at grain level, since film
cannot resolve detail finer than the grain clumps resulting from photons
'triggering' the entire grain to blacken. This is why fine-grain thin emulsion
films yield more lp/mm than coarser-grained films. Photography 101.

 

[Guest]

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Susan Perkins wrote:
>
> On Fri, 29 Oct 2004 14:52:46 -0600, in article <4182AD9B.B7007F9A@aol.com>, Tom
> Phillips <nospam777@aol.com> wrote:
>
> >
> >
> >Ken Alverson wrote:
> >>
> >> "Tom Phillips" <nospam777@aol.com> wrote in message
> >> news:41823255.BC08FE81@aol.com...
> >> >
> >> > Photography produces a photograph. And a photograph is an
> >> > image written on photosensitive materials by the direct
> >> > action of light. Digital imaging is electronic and about
> >> > as "photographic" as your television cameraman broadcasting
> >> > to your T.V. set. Again, no photograph.
> >>
> >> Photograph, from the greek "photo-" meaning light and "-graph" meaning
> >> recording. Whether the recording was made photochemically and stored on
> >> physical media or photoelectrically and stored on digital media is really
> >> inconsequential to its status as a photograph.
> >>
> >> Ken
> >
> >
> >No. it means (literally) light writing, i.e., as in physically
> >drawing with light.
> >
> >Digital sensors produce data.
>
> Yes, they produce data based on a light signature.

Give it a rest. You clearlty haven't a clue. And in
photoelectric effects there is no "light signature."
There are photoelectrons and a voltage.

>That is to say, their data

> is completely, 100 percent, dependent on light for generation. Without light,
> no data.

>The result is clearly "light writing" (or photography) to anyone
> except those who would argue about how many angels can dance on the head of a
> pin.

No photograph is produced. Electrons, voltage, and
according to the ISO which organization "writes" all
the standards your liitle digital P&S functions on, A
_signal_ that _represents_ a still picture.

Go chew on the ISO.

I'll stick with my 4x5 that no digital resolution can
ever match. A little thing called the Nyquist limitation
that applies to all electronic signals will forever
limit digital resolution, not to mention photodectors
simple cannot get as small as a silver halide molecule.
Not physically possible and still generate a signal.

Now, go back to your pinhead argument...

 

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Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital,rec.photo.equipment.35mm,rec.photo.film+labs,rec.photo.darkroom (More info?)

"Justín Käse" wrote:
>
> In Message-ID:<418360e9$0$15715$ba620e4c@news.skynet.be> posted on Sat,
> 30 Oct 2004 11:37:51 +0200, imbsysop wrote:
>
> >
> >"Justín Käse" <chupacabra@operamail.com> wrote in message
> >news:4183c6e0.7091124@chupacabra...
> >> In Message-ID:<4182b49f$0$7082$ba620e4c@news.skynet.be> posted on Fri,
> >> 29 Oct 2004 23:22:44 +0200, imbsysop wrote:
> >>
> >>>> Silver hailde exposure occurs at the molecular level.
> >>>
> >>>sure .. but not sure for how many molecules in the crystal ..
> >>
> >> Due to the cellular lattice* structure of crystals,
> >> if any molecule's affected, they all are, in that one crystal.
> >> Therefore, the amount of photons required to "expose" emulsions with
> >> larger crystals is less, making the emulsion react faster and the result
> >> appear grainier.
> >>
> >> *see Minkowski's theorem
> >
> >which makes film a lousy photo medium ?
> >
>
> I didn't say that,
> but if you want to troll up an argument, try that other guy, the one
> that's so full of non sequitur terminology, and will shift the
> conversation in a nanosecond rather than admit he erred.


This from a guy who doesn't know what a photoelectron is.

Go read a textbook on physics and photoelectric effect...

 

[Guest]

Archived from groups: alt.comp.periphs.dcameras,rec.photo.digital,rec.photo.equipment.35mm,rec.photo.film+labs,rec.photo.darkroom (More info?)

"jjs" <jjs@x.x.com> wrote in message
news:10o89bbj4rk4lf5@news.supernews.com...
> "William Graham" <weg9@comcast.net> wrote in message
> news:fiVgd.335836$3l3.5745@attbi_s03...
>> The rods and cones of the retina constitute a digital sensing plane, and
>> the brains interpretation of the scans (as you mention above) is the,
>> "software" that produces the final image.
>
> Most of the processing we are concerned with is in the retina. The brain
> couples to recognition of those signals, not interpretation of them.
>
>
Yes, but they have discovered that a surprising amount of what we, "see" is
actually interpretation by the brain of what is actually a rather poor
optical image. The brain fills in an amazing percentage of the picture,
based on its experience and memory. One might think of this, "filling in" as
part of the software package we develop starting at birth.