Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-19 Thread graywolf
Since it does not seem to be generally realized quantum foam is the 
current version of the unified field theory (any one remember ether?). I 
recently read a SF where the starship was powered by tapping the charge 
gradient of the quantum foam. Hence the battery comment. No, I do not 
think the author had any better idea what that means than I do.

Anyone who actually knows me would not mention Bud and my name in the 
same sentence without including the verb hates. Bud and Coors are the 
two brews I will not even drink when they are free.

-- 
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---


David Savage wrote:
> At 01:12 AM 19/09/2006, mike wilson wrote:
> 
>>> From: graywolf <[EMAIL PROTECTED]>
>>>
>>> For those of you who insist that quantum mechanics apply at the real
>>> world level, please send me a quart of quantum foam, I want to use it as
>>> a battery. Reading too much SF lately .
>> That would be a couple of bottles of Bud.  Battery acid by any name is 
>> still battery acid.  Foamy or not.
> 
> 
> Battery acid has more flavour
> 
> 
> Dave 
> 
> 

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread David Savage
At 01:12 AM 19/09/2006, mike wilson wrote:

> >
> > From: graywolf <[EMAIL PROTECTED]>
> >
> > For those of you who insist that quantum mechanics apply at the real
> > world level, please send me a quart of quantum foam, I want to use it as
> > a battery. Reading too much SF lately .
>
>That would be a couple of bottles of Bud.  Battery acid by any name is 
>still battery acid.  Foamy or not.


Battery acid has more flavour


Dave 


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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread DagT
You are missing the fact that the holes in this case is not in  
molecules but in crystals having energy gaps corresponding to certain  
energy levels, so they can move around a bit and get excited by both  
phonons (e.g, thermal) and photons.  Now, lets all jump into  
reciprocal space to look at it from another point of view...  .-)

DagT

Den 18. sep. 2006 kl. 20.24 skrev graywolf:

> Oh, lets make it more interesting. A hole is actually a molecule with
> one or more missing electrons, hence holes, that can be picked up,
> usually from an adjacent molecule. That explains all those moving  
> holes
> I had so much trouble understanding back when transistors came out.  
> And
> to finish off solid state electronics is made postible by having
> material that will give off, and receive electrons easily. Hence,  
> again,
> those moving holes.
>
> There, I have explained in one sentence what whole books have had
> trouble getting across , and no fair saying my explaination is
> over simplified.
>
> -- 
> graywolf
> http://www.graywolfphoto.com
> http://webpages.charter.net/graywolf
> "Idiot Proof" <==> "Expert Proof"
> ---
>
>
> Digital Image Studio wrote:
>> On 19/09/06, graywolf <[EMAIL PROTECTED]> wrote:
>>> Thanks, Toralf, I have skimmed that and bookmarked to read more  
>>> closely.
>>>
>>> Getting a bit of an Ah-Ha from that skim, apparently folks are  
>>> talking
>>> about electrons and holes as if they are the same thing. They  
>>> definately
>>> are not. A hole is a space that can accept an electron, and if we  
>>> are
>>> talking about 40K or so holes in the photodiode then that makes  
>>> sense as
>>> that would be the amount of additional free electrons that the  
>>> diode can
>>> accept (note that lots of them will bounce around and never find  
>>> a hole
>>> to fit into). Still in the real world sense the output can not be
>>> considered stepped but a fairly smooth analog curve. Sometimes we  
>>> try to
>>> apply too much to our understanding of things.
>>
>> Yes, but I don't know if here is the place to discuss Solid-state
>> technology in detail :-)
>>
>
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DagT
http://dag.foto.no

Beware of internet links. You never know what is on the other side.




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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread graywolf
Oh, lets make it more interesting. A hole is actually a molecule with 
one or more missing electrons, hence holes, that can be picked up, 
usually from an adjacent molecule. That explains all those moving holes 
I had so much trouble understanding back when transistors came out. And 
to finish off solid state electronics is made postible by having 
material that will give off, and receive electrons easily. Hence, again, 
those moving holes.

There, I have explained in one sentence what whole books have had 
trouble getting across , and no fair saying my explaination is 
over simplified.

-- 
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---


Digital Image Studio wrote:
> On 19/09/06, graywolf <[EMAIL PROTECTED]> wrote:
>> Thanks, Toralf, I have skimmed that and bookmarked to read more closely.
>>
>> Getting a bit of an Ah-Ha from that skim, apparently folks are talking
>> about electrons and holes as if they are the same thing. They definately
>> are not. A hole is a space that can accept an electron, and if we are
>> talking about 40K or so holes in the photodiode then that makes sense as
>> that would be the amount of additional free electrons that the diode can
>> accept (note that lots of them will bounce around and never find a hole
>> to fit into). Still in the real world sense the output can not be
>> considered stepped but a fairly smooth analog curve. Sometimes we try to
>> apply too much to our understanding of things.
> 
> Yes, but I don't know if here is the place to discuss Solid-state
> technology in detail :-)
> 

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread David J Brooks
Quoting Digital Image Studio <[EMAIL PROTECTED]>:

> On 19/09/06, graywolf <[EMAIL PROTECTED]> wrote:
>> Thanks, Toralf, I have skimmed that and bookmarked to read more closely.
>>
>> Getting a bit of an Ah-Ha from that skim, apparently folks are talking
>> about electrons and holes as if they are the same thing. They definately
>> are not. A hole is a space that can accept an electron, and if we are
>> talking about 40K or so holes in the photodiode then that makes sense as
>> that would be the amount of additional free electrons that the diode can
>> accept (note that lots of them will bounce around and never find a hole
>> to fit into). Still in the real world sense the output can not be
>> considered stepped but a fairly smooth analog curve. Sometimes we try to
>> apply too much to our understanding of things.
>
> Yes, but I don't know if here is the place to discuss Solid-state
> technology in detail :-)

What about tube radio's.:-)

Dave
>
> --
> Rob Studdert
> HURSTVILLE AUSTRALIA
> Tel +61-2-9554-4110
> UTC(GMT)  +10 Hours
> [EMAIL PROTECTED]
> http://home.swiftdsl.com.au/~distudio//publications/
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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread mike wilson

> 
> From: graywolf <[EMAIL PROTECTED]>
> 
> For those of you who insist that quantum mechanics apply at the real 
> world level, please send me a quart of quantum foam, I want to use it as 
> a battery. Reading too much SF lately .

That would be a couple of bottles of Bud.  Battery acid by any name is still 
battery acid.  Foamy or not.


-
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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread Digital Image Studio
On 19/09/06, graywolf <[EMAIL PROTECTED]> wrote:
> Thanks, Toralf, I have skimmed that and bookmarked to read more closely.
>
> Getting a bit of an Ah-Ha from that skim, apparently folks are talking
> about electrons and holes as if they are the same thing. They definately
> are not. A hole is a space that can accept an electron, and if we are
> talking about 40K or so holes in the photodiode then that makes sense as
> that would be the amount of additional free electrons that the diode can
> accept (note that lots of them will bounce around and never find a hole
> to fit into). Still in the real world sense the output can not be
> considered stepped but a fairly smooth analog curve. Sometimes we try to
> apply too much to our understanding of things.

Yes, but I don't know if here is the place to discuss Solid-state
technology in detail :-)

-- 
Rob Studdert
HURSTVILLE AUSTRALIA
Tel +61-2-9554-4110
UTC(GMT)  +10 Hours
[EMAIL PROTECTED]
http://home.swiftdsl.com.au/~distudio//publications/
Pentax user since 1986, PDMLer since 1998

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread graywolf
Thanks, Toralf, I have skimmed that and bookmarked to read more closely.

Getting a bit of an Ah-Ha from that skim, apparently folks are talking 
about electrons and holes as if they are the same thing. They definately 
are not. A hole is a space that can accept an electron, and if we are 
talking about 40K or so holes in the photodiode then that makes sense as 
that would be the amount of additional free electrons that the diode can 
accept (note that lots of them will bounce around and never find a hole 
to fit into). Still in the real world sense the output can not be 
considered stepped but a fairly smooth analog curve. Sometimes we try to 
apply too much to our understanding of things.

For those of you who insist that quantum mechanics apply at the real 
world level, please send me a quart of quantum foam, I want to use it as 
a battery. Reading too much SF lately .

-- 
graywolf
http://www.graywolfphoto.com
http://webpages.charter.net/graywolf
"Idiot Proof" <==> "Expert Proof"
---


Toralf Lund wrote:
>> So you are saying a 22 bit ADC is overkill. Wonder if Pentax knows that?
>>   
> The marketing people probably don't know, or care; they only know they 
> can quote a higher number than the competitors.
> 
> The engineers probably deliberately chose to have extra bits, so as to 
> avoid problems with accumulating round-off errors etc. in the processing 
> stages.
>> BTW, Rob's explanation was clearer, but still not documented for my 
>> curiosity.
>>   
> I'm not sure this can be considered an authoritative reference, but at 
> least it contains some actual numbers:
> 
> http://micro.magnet.fsu.edu/primer/digitalimaging/concepts/dynamicrange.html
> 
> - Toralf
> 
> 

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RE: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread Antti-Pekka Virjonen
Toralf,

I think you got it all just right and I believe we were both 
talking about the same thing in the first place :-). Sometimes
it just takes a lot of writing when trying to describe not so easy
things.

I have to admit I wasn't looking too deep into the DSLR ccd data
sheets when trying to figure out why they chose 22 bits.
Plus, it is not very easy to get the bare foot data from the
current sheets, since the ccd manufacturers seem to be 
hiding the basic facts to get more of their sensors sold (?).
Astronomical sensors generally have quite big pixel sizes
(but there are quite small as well, comparable to DSLR).

The smaller the wells, the higher the noise (because of the
smaller area to capture photons and smaller space to store 
electrons. Making better signal processing stages is one
way (maybe the only one at this time) to improve the results.
Pentax seems to be ahead of the competition with the new 
(to DSLR world) approach when using better designed signal 
processing.

Let us hope there will also be better sensors in the future :-).

Actually the only negative thing I have with the K10D is
I hoped they would incorporate a full frame sensor to get more
sensitivity and lower noise (more exposure latitude). But maybe 
it would have competed with their coming 645D too much.

BTW I did preorder my K10D today! 

It will be exciting to see the sample photos of production model
K10D. I think what we will see is a little different digital pictures
(closer to film kind of images). But I have been proven wrong before...

Antti-Pekka



Antti-Pekka Virjonen

Computec Oy
R&D Turku

www.computec.fi

> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf
> Of Toralf Lund
> Sent: Monday, September 18, 2006 3:41 PM
> To: Pentax-Discuss Mail List
> Subject: Re: It is ingenious! Was: Does this mean what I think it
> means?
> 
> Antti-Pekka Virjonen wrote:
> >> I think the actual sensors do have the 14-16 bits you mention - [
> ... ]
> >>
> >>
> >
> > Hi,
> >
> > Yes, actually I was talking about usable bits, taking the noise into
> > account, thus giving 14-16bits of usable data.
> >
> > This is so at least with the good quality astronomical ccd sensors
> but I
> >
> > am sure the DSLR camera sensors are coming close nowadays (or am I
> just
> > hoping?).
> >
> As has also been mentioned many times, the max. charge or "full-well"
> capacity of the sensor depends directly on the pixel area. Apparently
> it's approximately 1000 electrons per square micrometer in a normal
> CCD
> 
> I'm not sure about astronomical sensors, but in the linear CCDs I've
> used at work, the pixels are 12x12 or 14x14 micrometers, which should
> give you 2-3 times the data required for 16 bits. That may not be
> quite
> enough to leave you with 16 "good" bits after you've thrown away the
> noise, but 14 should be no problem.
> 
> On a DSLR, on the other hand, the pixel size has been something like
> 8x8
> microns for a while now, but on the latest (10MP) cameras, it's down
> to
> 6x6 or so. In other words, the DSLRs cameras are not "coming close";
> they are actually moving further away in that the pixels keep getting
> smaller!
> 
> A different side of this is obviously the noise situation. You can
> also
> improve the number of usable bits by reducing the noise, and this is
> an
> area where the DLSRs probably are getting better - but they also have
> to, in order to compensate for the smaller pixels. And it wouldn't
> surprise me if the astronomical sensors have very low noise, too.
> > In any case, when designing measuring systems (using amplifiers and
> a/d
> > converters) it is a good thing to have plenty of more bits and
> precision
> > compared to the original signal. This way you will minimize the
> added
> > noise. When having a 22 bits a/d converter on the K10D you can also
> > measure and analyze the "noise" of the low expusure pixels. You will
> get
> > all the available information out of the sensor.
> >
> Yes. It definitely seems like I good thing to keep *all* the info for
> the early image processing stages. Also, having some extra bits around
> will minimise round-off errors that might accumulate across multiple
> pixel value adjustment steps. You may think of extra bits as more
> decimals in intermediate results. I think this may be the most
> important
> consideration behind the choice of 22 bits.
> 
> - Toralf
> 
> 
> 
> 
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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread Toralf Lund

> So you are saying a 22 bit ADC is overkill. Wonder if Pentax knows that?
>   
The marketing people probably don't know, or care; they only know they 
can quote a higher number than the competitors.

The engineers probably deliberately chose to have extra bits, so as to 
avoid problems with accumulating round-off errors etc. in the processing 
stages.
> BTW, Rob's explanation was clearer, but still not documented for my 
> curiosity.
>   
I'm not sure this can be considered an authoritative reference, but at 
least it contains some actual numbers:

http://micro.magnet.fsu.edu/primer/digitalimaging/concepts/dynamicrange.html

- Toralf


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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-18 Thread Toralf Lund
Antti-Pekka Virjonen wrote:
>> I think the actual sensors do have the 14-16 bits you mention - [ ... ]
>>
>> 
>
> Hi,
>
> Yes, actually I was talking about usable bits, taking the noise into
> account, thus giving 14-16bits of usable data.
>   
> This is so at least with the good quality astronomical ccd sensors but I
>
> am sure the DSLR camera sensors are coming close nowadays (or am I just
> hoping?). 
>   
As has also been mentioned many times, the max. charge or "full-well" 
capacity of the sensor depends directly on the pixel area. Apparently 
it's approximately 1000 electrons per square micrometer in a normal CCD

I'm not sure about astronomical sensors, but in the linear CCDs I've 
used at work, the pixels are 12x12 or 14x14 micrometers, which should 
give you 2-3 times the data required for 16 bits. That may not be quite 
enough to leave you with 16 "good" bits after you've thrown away the 
noise, but 14 should be no problem.

On a DSLR, on the other hand, the pixel size has been something like 8x8 
microns for a while now, but on the latest (10MP) cameras, it's down to 
6x6 or so. In other words, the DSLRs cameras are not "coming close"; 
they are actually moving further away in that the pixels keep getting 
smaller!

A different side of this is obviously the noise situation. You can also 
improve the number of usable bits by reducing the noise, and this is an 
area where the DLSRs probably are getting better - but they also have 
to, in order to compensate for the smaller pixels. And it wouldn't 
surprise me if the astronomical sensors have very low noise, too.
> In any case, when designing measuring systems (using amplifiers and a/d 
> converters) it is a good thing to have plenty of more bits and precision
> compared to the original signal. This way you will minimize the added
> noise. When having a 22 bits a/d converter on the K10D you can also
> measure and analyze the "noise" of the low expusure pixels. You will get
> all the available information out of the sensor.
>   
Yes. It definitely seems like I good thing to keep *all* the info for 
the early image processing stages. Also, having some extra bits around 
will minimise round-off errors that might accumulate across multiple 
pixel value adjustment steps. You may think of extra bits as more 
decimals in intermediate results. I think this may be the most important 
consideration behind the choice of 22 bits.

- Toralf




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RE: It is ingenious! Was: Does this mean what I think it means?

2006-09-17 Thread Antti-Pekka Virjonen
> I think the actual sensors do have the 14-16 bits you mention - which
> literally means that the max charge is up to some 65000 electrons.
> However, they also have a readout noise of at least 10 electrons,
> which
> is equivalent to 3 or 4 bits. This essentially means that you are left
> with a usable dynamic range or latitude equivalent to 12 bits; any
> additional bits would just be "measuring the noise", if they contained
> any information at all. That's why a 12-bit A/D is traditionally used.
> 
> Furthermore, when you amplify the signal for a higher ISO setting, you
> also amplify the noise, thus shifting up the 3 or 4 bits so that
> contain
> noise, so it enters even the 12 bits you keep.
> 
> But like I said, this has been discussed a lot in the past few weeks.
> In
> in several rounds before that, too. Enough for now.
> 
> I'm not sure I've read the data sheets of the *exact* sensors used in
> the Pentax cameras, either, by the way (I've seen technical data for
> various ones of similar type...)
> 
> - Toralf

Hi,

Yes, actually I was talking about usable bits, taking the noise into
account, thus giving 14-16bits of usable data.

This is so at least with the good quality astronomical ccd sensors but I

am sure the DSLR camera sensors are coming close nowadays (or am I just
hoping?). 

In any case, when designing measuring systems (using amplifiers and a/d 
converters) it is a good thing to have plenty of more bits and precision
compared to the original signal. This way you will minimize the added
noise. When having a 22 bits a/d converter on the K10D you can also
measure and analyze the "noise" of the low expusure pixels. You will get
all the available information out of the sensor.

Antti-Pekka




Antti-Pekka Virjonen

Computec Oy
R&D Turku

www.computec.fi



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RE: It is ingenious! Was: Does this mean what I think it means?

2006-09-17 Thread Antti-Pekka Virjonen
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf
> Of graywolf
> Sent: Friday, September 15, 2006 5:37 PM
> To: Pentax-Discuss Mail List
> Subject: Re: It is ingenious! Was: Does this mean what I think it
> means?
> 
> Lets back up a bit here. You have a sensor that has an analog out put.
> You send that output to an analog to digital converter. The converter
> produces an 8, or 10, or 12, or in this case 22 bit digital
> representation of the analog signal. Then that digital representation
> is
> processed digitally. Note that the analog signal does not change. The
> only difference is that the higher bit rates produce a more accurate
> representation of the analog signal. There is no magic here, just
> technology.
> 
> Rephrasing that, the analog signal is simply broken up into more
> digital
> pieces, nothing is added to it.
> 
> --
> graywolf
> http://www.graywolfphoto.com
> http://webpages.charter.net/graywolf
> "Idiot Proof" <==> "Expert Proof"

Hi,

I did not say the digital processing would add anything else than noise!

If you look closely at the "if" part:

Yes, it has to decide the exposure time and f-stop but *IF* the imaging
*AND* image processing has a really wide dynamic range you can still 
choose the correctly exposed part of that range (choose the most
fitting 12 bits space from the full 22 bit space for example).

With *imaging* I mean the sensor and with *image processing* I mean
the analog amplifier stage and the a/d conversion.

Sorry for maybe not being very clear (English not my first language).
In another e-mail to this thread I already said this was going into 
a bit too technical (and theoretical). I know there is no magic in the
electronics design (I do it at work) but sometimes I sure feel like
a magician...

At least in theory (and I am sure we will see that partly in practice
with the K10D), using a higher bit depth in the a/d stage is a really
good thing to do.

Antti-Pekka


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Computec Oy
R&D Turku

www.computec.fi


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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-16 Thread Digital Image Studio
On 17/09/06, graywolf <[EMAIL PROTECTED]> wrote:
> So you are saying a 22 bit ADC is overkill. Wonder if Pentax knows that?
> BTW, Rob's explanation was clearer, but still not documented for my
> curiosity.

A theoretically perfect 22 bit ADC should be able to resolve 4,194,304
voltage levels between zero and it the voltage represented by all bits
at 1. This is clearly overkill given the noise figures of the source
device, if the ADC was 18 bits I'm sure you'd be seeing far less
discussion regarding the validity of sampling at such high resolution.
I'll try to dredge up some decent links on the subject.

Personally I'm sure that the mention of 22 bits is true but purely
marketing hype. In in the case of the K10D it's great marketing
fodder, regardless of the fact that it's overkill or not. The chip
that they've likely used is is marketed as a generic imaging system
building block which when coupled with an appropriate sensor (and
cooling system) may be entirely justifiable.

Let's just hope that in the case of the K10D the pre-processing stages
following the ADC live up to the hype and deliver a very usable 12 bit
RAW image file.


-- 
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HURSTVILLE AUSTRALIA
Tel +61-2-9554-4110
UTC(GMT)  +10 Hours
[EMAIL PROTECTED]
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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-16 Thread graywolf
So you are saying a 22 bit ADC is overkill. Wonder if Pentax knows that?
BTW, Rob's explanation was clearer, but still not documented for my 
curiosity.

-- 
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http://www.graywolfphoto.com
http://webpages.charter.net/graywolf
"Idiot Proof" <==> "Expert Proof"
---


John Francis wrote:
> On Sat, Sep 16, 2006 at 05:45:09PM -0400, graywolf wrote:
>> Can you provide a reference on that? A quick goggle search* finds 
>> nothing the contradicts my explanation. Your comment may be accurate on 
>> the quantum level but I do not think we can quite apply it to current 
>> image sensors, but would be interested in seeing something about where 
>> you are getting that from. Photons, like all quantum particles, are very 
>> slippery critters and probably act that way, but I do not know of any 
>> photo diode that gives out a quantized signal --in a macro world sense. 
> 
> The point is that you're not in a macro world.  The change in voltage level
> that would be indicated by the smallest possible change in a 22-bit number
> is well below the change in voltage that would be caused by the presence of
> just one additional electron in the sensor site (by a couple of orders of
> magnitude).  You're trying to measure an "analog" quantity to a precision
> that puts you firmly in the quantum domain.
> 
> 

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-16 Thread John Francis
On Sat, Sep 16, 2006 at 05:45:09PM -0400, graywolf wrote:
> Can you provide a reference on that? A quick goggle search* finds 
> nothing the contradicts my explanation. Your comment may be accurate on 
> the quantum level but I do not think we can quite apply it to current 
> image sensors, but would be interested in seeing something about where 
> you are getting that from. Photons, like all quantum particles, are very 
> slippery critters and probably act that way, but I do not know of any 
> photo diode that gives out a quantized signal --in a macro world sense. 

The point is that you're not in a macro world.  The change in voltage level
that would be indicated by the smallest possible change in a 22-bit number
is well below the change in voltage that would be caused by the presence of
just one additional electron in the sensor site (by a couple of orders of
magnitude).  You're trying to measure an "analog" quantity to a precision
that puts you firmly in the quantum domain.


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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-16 Thread Digital Image Studio
On 17/09/06, graywolf <[EMAIL PROTECTED]> wrote:
> Can you provide a reference on that? A quick goggle search* finds
> nothing the contradicts my explanation. Your comment may be accurate on
> the quantum level but I do not think we can quite apply it to current
> image sensors, but would be interested in seeing something about where
> you are getting that from. Photons, like all quantum particles, are very
> slippery critters and probably act that way, but I do not know of any
> photo diode that gives out a quantized signal --in a macro world sense.
>   I admit my physics knowledge is not as up to date as it could be. But
> I do believe folks are trying to digitalize non-digital phenomena, if
> the information was digital we would not need an ADC.

It's still an analogue signal it's just not continuous, an ADC is
still required in order to produce digital representations of the
voltage levels. You have to consider that real size of the photo diode
component of the sensor. Its width is only tens of wavelengths
(considering active sensitivity to about 700nm) across (6.05 x 6.05um)
in the case of the sensor in the K10D and it may only be two or three
atoms deep, this is why numbers like 40k electrons for saturation are
being bandied about (though I suspect that the sensor in the K10D
would be closer to about 32k, unfortunately Sony specs aren't direct
comparable with those from the majority of other manufacturers). It's
a bit mind contorting but the analogue output of the sensor is
governed by the electron count so if the devices were noiseless you
would see discrete steps in the analogue output.

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-16 Thread graywolf
Can you provide a reference on that? A quick goggle search* finds 
nothing the contradicts my explanation. Your comment may be accurate on 
the quantum level but I do not think we can quite apply it to current 
image sensors, but would be interested in seeing something about where 
you are getting that from. Photons, like all quantum particles, are very 
slippery critters and probably act that way, but I do not know of any 
photo diode that gives out a quantized signal --in a macro world sense. 
  I admit my physics knowledge is not as up to date as it could be. But 
I do believe folks are trying to digitalize non-digital phenomena, if 
the information was digital we would not need an ADC.

*Unfortunately, the liberal arts university here in Boone does not have 
much in the way of science texts in its library (singular). Sigh, I do 
miss having the U of M libraries at my fingertips, so to speak.


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John Francis wrote:
> On Sat, Sep 16, 2006 at 02:47:56PM -0400, graywolf wrote:
>> Still trying to turn things around. The sensor is simply a photocell. 
>> The brighter the light hitting it the higher the voltage output. 
>> Visualize analog as curves, digital as steps. Don't get them crossed in 
>> your mind if you want to understand what is going on.
> 
> Unfortunately, Tom, you're incorrect here.  The "analog" output
> from that sensor is still quantized into discrete steps (either
> the number of electrons in the well, or the number of photons
> that hit the sensor - take your pick).  Both of those numbers
> are below 2^17 (around 128000).  So you're never going to get
> more than that many different values in your digital output.
> (Or in your "analog" input curve, either, if you look closely).
> 
> 
> 

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-16 Thread John Francis
On Sat, Sep 16, 2006 at 02:47:56PM -0400, graywolf wrote:
> Still trying to turn things around. The sensor is simply a photocell. 
> The brighter the light hitting it the higher the voltage output. 
> Visualize analog as curves, digital as steps. Don't get them crossed in 
> your mind if you want to understand what is going on.

Unfortunately, Tom, you're incorrect here.  The "analog" output
from that sensor is still quantized into discrete steps (either
the number of electrons in the well, or the number of photons
that hit the sensor - take your pick).  Both of those numbers
are below 2^17 (around 128000).  So you're never going to get
more than that many different values in your digital output.
(Or in your "analog" input curve, either, if you look closely).



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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-16 Thread graywolf
Still trying to turn things around. The sensor is simply a photocell. 
The brighter the light hitting it the higher the voltage output. 
Visualize analog as curves, digital as steps. Don't get them crossed in 
your mind if you want to understand what is going on. All the talk about 
sensors like they are photon counters is pretty counter-productive also, 
as they definitely are not. It is not like they have a capacity of x 
photons, but that at a certain point the out put voltage cannot go any 
higher even if the light is brighter. If you have ever used an old 
fashioned light meter with a swinging needle, think of a sensor as an 
super tiny array of them. The ADC converts the voltage into a digital 
signal with the voltage as a binary number. At this point we are still 
dealing with the output of a single pixel, the next step is integrating 
all those signals that is where it gets complicated.

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Jim King wrote:
>> Lets back up a bit here. You have a sensor that has an analog out put.
>> You send that output to an analog to digital converter. The converter
>> produces an 8, or 10, or 12, or in this case 22 bit digital
>> representation of the analog signal. Then that digital  
>> representation is
>> processed digitally. Note that the analog signal does not change. The
>> only difference is that the higher bit rates produce a more accurate
>> representation of the analog signal. There is no magic here, just
>> technology.
>>
>> Rephrasing that, the analog signal is simply broken up into more  
>> digital
>> pieces, nothing is added to it.
> 
> But the analog signal output is not a smooth curve; it is a stepped  
> voltage representing the capture of from 0 to about 50,000  
> electrons.  Sampling at 22 bits will simply give a number of similar  
> outputs for each step where the voltage is the same.  The benefit  
> will come from averaging these to reduce noise.  At least that is how  
> I envision it...
> 
> Regards, Jim
> 

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-15 Thread Jim King
graywolf wrote on Fri, 15 Sep 2006 07:39:11 -0700

> Lets back up a bit here. You have a sensor that has an analog out put.
> You send that output to an analog to digital converter. The converter
> produces an 8, or 10, or 12, or in this case 22 bit digital
> representation of the analog signal. Then that digital  
> representation is
> processed digitally. Note that the analog signal does not change. The
> only difference is that the higher bit rates produce a more accurate
> representation of the analog signal. There is no magic here, just
> technology.
>
> Rephrasing that, the analog signal is simply broken up into more  
> digital
> pieces, nothing is added to it.

But the analog signal output is not a smooth curve; it is a stepped  
voltage representing the capture of from 0 to about 50,000  
electrons.  Sampling at 22 bits will simply give a number of similar  
outputs for each step where the voltage is the same.  The benefit  
will come from averaging these to reduce noise.  At least that is how  
I envision it...

Regards, Jim

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-15 Thread Toralf Lund

>> It's been mentioned about two point six zillion times by now that you
>> probably don't, though. The sensor itself doesn't have a lot more than
>> 12-bits worth of latitude, so producing more bits in the A/D doesn't
>> help a lot.
>> 
>
> I disagree with that a little. It's still the same sensor reveiving the 
> photons no matter if you set the ISO to 100 or 1600 in a normal
> DSLR. When setting the camera to ISO 1600 you just capture a lot
> less photons in one pixel well than you would if you set ISO 100
> (having the same amount of light available on both exposures). This
> is because you will have less light entering the sensor to get the
> correct exposure. Every single photon generates one electon (not
> exactly but to about 70% success rate) and there is a lot of
> space for those electrons. A good modern CCD sensor does have 14-16 bits
> worth of depth (or latitude). Don't know about these DSLR camera
> sensors though, maybe they are just 12 bits :(. 
I think the actual sensors do have the 14-16 bits you mention - which 
literally means that the max charge is up to some 65000 electrons. 
However, they also have a readout noise of at least 10 electrons, which 
is equivalent to 3 or 4 bits. This essentially means that you are left 
with a usable dynamic range or latitude equivalent to 12 bits; any 
additional bits would just be "measuring the noise", if they contained 
any information at all. That's why a 12-bit A/D is traditionally used.

Furthermore, when you amplify the signal for a higher ISO setting, you 
also amplify the noise, thus shifting up the 3 or 4 bits so that contain 
noise, so it enters even the 12 bits you keep.

But like I said, this has been discussed a lot in the past few weeks. In 
in several rounds before that, too. Enough for now.

I'm not sure I've read the data sheets of the *exact* sensors used in 
the Pentax cameras, either, by the way (I've seen technical data for 
various ones of similar type...)

- Toralf


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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-15 Thread graywolf
Lets back up a bit here. You have a sensor that has an analog out put. 
You send that output to an analog to digital converter. The converter 
produces an 8, or 10, or 12, or in this case 22 bit digital 
representation of the analog signal. Then that digital representation is 
processed digitally. Note that the analog signal does not change. The 
only difference is that the higher bit rates produce a more accurate 
representation of the analog signal. There is no magic here, just 
technology.

Rephrasing that, the analog signal is simply broken up into more digital 
pieces, nothing is added to it.

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Antti-Pekka Virjonen wrote:
>> -Original Message-
>> It's been mentioned about two point six zillion times by now that you
>> probably don't, though. The sensor itself doesn't have a lot more than
>> 12-bits worth of latitude, so producing more bits in the A/D doesn't
>> help a lot.
> 
> I disagree with that a little. It's still the same sensor reveiving the 
> photons no matter if you set the ISO to 100 or 1600 in a normal
> DSLR. When setting the camera to ISO 1600 you just capture a lot
> less photons in one pixel well than you would if you set ISO 100
> (having the same amount of light available on both exposures). This
> is because you will have less light entering the sensor to get the
> correct exposure. Every single photon generates one electon (not
> exactly but to about 70% success rate) and there is a lot of
> space for those electrons. A good modern CCD sensor does have 14-16 bits
> worth of depth (or latitude). Don't know about these DSLR camera
> sensors though, maybe they are just 12 bits :(. That would be a little
> disappointing, heh. (Ok, I need to do some CCD data sheet reading I 
> guess).
> 
> If you shoot at 1600, the amplifier gain is set high because
> less photon generated electrons are available to be read from the CCD 
> wells to get the output voltage values for all the pixels in the picture
> to closely fill the full dynamic range of the following a/d converter.
> The overexposed cells or wells (still far from flowing over) overflow
> the amplifier (at the set gain) and the a/d reads full scale value for
> those "pixels" (overexposure).
> 
> If you set the same camera to lower ISO (like 100). You still use the
> same ccd, just the wells of the sensor get a lot more photons and
> a lot more electrons are generated. Then you use a lower gain amplifier 
> to get the output matched as close as possible to the input range of the
> 
> a/d conversion.
> 
> When using the 22 bits a/d you can have a lower gain amplifier and then
> choose the suitable part of the full scale input of the a/d converter to
> get the (for example) 12 bits of the wanted exposure and latitude (which
> 
> is a small part of the whole dynamic range of the conversion).
> At least, this is how I believe it could work in theory. In real world
> the CCD well depth vs. noise level (dynamic range) is of course less
> than 22 bits but you still can have an optimized fixed gain amplifier.
> It is a lot more easier to design a good fixed gain amp than a variable 
> one.
>  
>> Not amplifying the signal (in a variable manner) probably does help *a
>> bit* as one source of noise has been removed (and the 12 bits are the
>> latitude after noise has been chopped off), but it's probably not too
>> significant compared to the noise in the actual sensor and/or the
>> interface to it.
>>
>> - Toralf
> 
> Of course, the real world "gain" from all this technology is not 
> world breaking but I think we may well notice an easily visible 
> difference between Pentax and the current competition. I don't think
> either that we can set the post prosessing ISO value from the whole
> 100-1600 range, but I am pretty convinced there will be an advantage
> over the current models.
> 
> It would be nice if they would explain exactly why they decided to
> have 22 bits of a/d.
> 
> This got a bit too technical... I even did some amplifier design today 
> and looked at bit too deep into the future *grin*.
> 
> Can't help it, being an electronics design engineer...
> 
> Let's just wait and see,
> Antti-Pekka
> 
> 
> Antti-Pekka Virjonen
> 
> Computec Oy
> R&D Turku
> 
> www.computec.fi
> 
> 
> 

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RE: It is ingenious! Was: Does this mean what I think it means?

2006-09-15 Thread Antti-Pekka Virjonen
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf
> Of Hans Imglueck
> Sent: Friday, September 15, 2006 9:30 AM
> To: Pentax-Discuss Mail List
> Subject: Re: It is ingenious! Was: Does this mean what I think it
> means?
> 
> Hi,
> 
> but the camera has to choose the exposure time for the shot and
> therefore everything is fixed after the exposure. Setting an ISO in
> a digital camera is just another word for under- or overexposure. So
> I think what you discribe is just not possible - but a nice
> imagination!
> 
> Best regards, Hans.

Yes, it has to decide the exposure time and f-stop but if the imaging
and image processing has a really wide dynamic range you can still 
choose the correctly exposed part of that range (choose the most
fitting 12 bits space from the full 22 bit space for example).

I guess we'll have to wait and see,
Antti-Pekka


Antti-Pekka Virjonen

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RE: It is ingenious! Was: Does this mean what I think it means?

2006-09-15 Thread Antti-Pekka Virjonen
> -Original Message-
> It's been mentioned about two point six zillion times by now that you
> probably don't, though. The sensor itself doesn't have a lot more than
> 12-bits worth of latitude, so producing more bits in the A/D doesn't
> help a lot.

I disagree with that a little. It's still the same sensor reveiving the 
photons no matter if you set the ISO to 100 or 1600 in a normal
DSLR. When setting the camera to ISO 1600 you just capture a lot
less photons in one pixel well than you would if you set ISO 100
(having the same amount of light available on both exposures). This
is because you will have less light entering the sensor to get the
correct exposure. Every single photon generates one electon (not
exactly but to about 70% success rate) and there is a lot of
space for those electrons. A good modern CCD sensor does have 14-16 bits
worth of depth (or latitude). Don't know about these DSLR camera
sensors though, maybe they are just 12 bits :(. That would be a little
disappointing, heh. (Ok, I need to do some CCD data sheet reading I 
guess).

If you shoot at 1600, the amplifier gain is set high because
less photon generated electrons are available to be read from the CCD 
wells to get the output voltage values for all the pixels in the picture
to closely fill the full dynamic range of the following a/d converter.
The overexposed cells or wells (still far from flowing over) overflow
the amplifier (at the set gain) and the a/d reads full scale value for
those "pixels" (overexposure).

If you set the same camera to lower ISO (like 100). You still use the
same ccd, just the wells of the sensor get a lot more photons and
a lot more electrons are generated. Then you use a lower gain amplifier 
to get the output matched as close as possible to the input range of the

a/d conversion.

When using the 22 bits a/d you can have a lower gain amplifier and then
choose the suitable part of the full scale input of the a/d converter to
get the (for example) 12 bits of the wanted exposure and latitude (which

is a small part of the whole dynamic range of the conversion).
At least, this is how I believe it could work in theory. In real world
the CCD well depth vs. noise level (dynamic range) is of course less
than 22 bits but you still can have an optimized fixed gain amplifier.
It is a lot more easier to design a good fixed gain amp than a variable 
one.
 
> Not amplifying the signal (in a variable manner) probably does help *a
> bit* as one source of noise has been removed (and the 12 bits are the
> latitude after noise has been chopped off), but it's probably not too
> significant compared to the noise in the actual sensor and/or the
> interface to it.
> 
> - Toralf

Of course, the real world "gain" from all this technology is not 
world breaking but I think we may well notice an easily visible 
difference between Pentax and the current competition. I don't think
either that we can set the post prosessing ISO value from the whole
100-1600 range, but I am pretty convinced there will be an advantage
over the current models.

It would be nice if they would explain exactly why they decided to
have 22 bits of a/d.

This got a bit too technical... I even did some amplifier design today 
and looked at bit too deep into the future *grin*.

Can't help it, being an electronics design engineer...

Let's just wait and see,
Antti-Pekka


Antti-Pekka Virjonen

Computec Oy
R&D Turku

www.computec.fi



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Re: Does this mean what I think it means?

2006-09-15 Thread Toralf Lund

> Hi,
>
> French is my mother tongue (as my name suggests), and I can say that the 
> babelfish translation is accurate in saying that it is "possible to 
> *act* on ... the ISO adjustment".
>
> To my ears this means that the ISO can be somehow (?) set at 
> post-processing.
>
> How they achieve such a result while storing only the 12bits in the RAW 
> file is still a mystery to me. I wouldn't say so if at least 4 more bits 
> were stored into the RAW.
>   
I'm not sure I understand how that would help. Haven't we written off 
those bits as containing only random variation caused by noise?

Not that I necessarily think it's a bad idea to use 22 bits internally, 
either. It does seem right somehow to apply some of the processing on 
data that contains all info, *including noise* - but I don't think it is 
significantly different in terms of image quality.
> Otherwise, with a 12bit RAW, +1 EV push gives roughly 11 useful bits, +4 
> EV (100->1600) gives only 8 useful bits => nothing I can't do with my 
> *ist DS...
>   
But do you have more than 8 useful  when setting the camera at 1600? 
Again, considering the noise situation.

- Toralf

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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-15 Thread Toralf Lund

> Hi,
>
> Wanted to add: 
> Maybe the raw files contain the 22 bit data. If so, you can set the ISO
> to anything you wish in the post prosessing (and as many times as you
> wish).
>   
May guess is this:

The signal is converted into 22 bits without a variable gain stage (like 
you say). The ISO setting is then applied in the image processor, along 
with various other (optional) adjustment steps, and the processed data 
is output as a 12-bit "raw" image. But the unprocessed input data is 
also saved temporarily, and may be run through the image processor 
additional times, if you change the processing parameters on the camera.

Whether this "fully unprocessed" data can actually be read out, is a 
different matter.


>
> 5) With a relatively low gain amplifier and 22 bit A/D (and both having
> low 
> noise) you will get a really wide exposure latitude. The K10D differs
> from the competition in this respect. It is like how negative film
> differs from 
> slide film.
>   
It's been mentioned about two point six zillion times by now that you 
probably don't, though. The sensor itself doesn't have a lot more than 
12-bits worth of latitude, so producing more bits in the A/D doesn't 
help a lot.

Not amplifying the signal (in a variable manner) probably does help *a 
bit* as one source of noise has been removed (and the 12 bits are the 
latitude after noise has been chopped off), but it's probably not too 
significant compared to the noise in the actual sensor and/or the 
interface to it.

- Toralf


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Re: It is ingenious! Was: Does this mean what I think it means?

2006-09-14 Thread Hans Imglueck
Hi,

but the camera has to choose the exposure time for the shot and
therefore everything is fixed after the exposure. Setting an ISO in
a digital camera is just another word for under- or overexposure. So
I think what you discribe is just not possible - but a nice imagination!

Best regards, Hans.


 Original-Nachricht 
Datum: Fri, 15 Sep 2006 08:45:01 +0300
Von: "Antti-Pekka Virjonen" <[EMAIL PROTECTED]>
An: "Pentax-Discuss Mail List" 
Betreff: It is ingenious! Was: Does this mean what I think it means?

> Hi,
> 
> I was thinking about the 22 bit A/D converter and about the ISO 
> setting last night.
> 
> Then it struck me, right into the back of my head... :-)
> 
> It is simply ingenious (if this is what Pentax has done):
> 
> 1) By utilizing a 22 bit A/D you get a wide dynamic range
> 
> 2) When you have a wide dynamic range on the A/D converter, you don't
> have to
> use a high gain amplifier stage (to get high ISO sensitivity) but you
> can use
> a constant (lower) gain low noise (optimized) amplifier.
> 
> 3) This way you can "choose" the ISO setting after exposure, before
> storing 
> the image into the raw (or converting to jpg). You can analyze the data
> and
> then decide "how to actually expose". I think this is what Pentax may be
> doing 
> with the "automatic ISO setting". It's like having all the different ISO
> 
> negative films in your camera the same time.
> 
> (Of course you can have a variable gain amp if you wish to get
> "standard"
> DSLR behaviour...)
> 
> 5) With a relatively low gain amplifier and 22 bit A/D (and both having
> low 
> noise) you will get a really wide exposure latitude. The K10D differs
> >from the competition in this respect. It is like how negative film
> differs from 
> slide film.
> 
> In theory you will get a very nice package. We'll see how it will
> perform
> in reality, but I am sure it will do quite nicely. Pentax wouldn't have
> used a 22 bits A/D if there wasn't a good reason. 
> 
> Antti-Pekka
> 
> 
> 
> Antti-Pekka Virjonen
> 
> Computec Oy
> R&D Turku
> Fiskarsinkatu 7 D
> FIN-20750 Turku Finland
> 
> Puh. +358 20 7908 300
> GSM +358 500 789 753
> Telefax +358 20 7908 319
> 
> Y-tunnus 1974184-5
> Kotipaikka Helsinki
> 
> www.computec.fi
> 
> 
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It is ingenious! Was: Does this mean what I think it means?

2006-09-14 Thread Antti-Pekka Virjonen
Hi,

Wanted to add: 
Maybe the raw files contain the 22 bit data. If so, you can set the ISO
to anything you wish in the post prosessing (and as many times as you
wish).

I wrote:
---

I was thinking about the 22 bit A/D converter and about the ISO 
setting last night.

Then it struck me, right into the back of my head... :-)

It is simply ingenious (if this is what Pentax has done):

1) By utilizing a 22 bit A/D you get a wide dynamic range

2) When you have a wide dynamic range on the A/D converter, you don't
have to
use a high gain amplifier stage (to get high ISO sensitivity) but you
can use
a constant (lower) gain low noise (optimized) amplifier.

3) This way you can "choose" the ISO setting after exposure, before
storing 
the image into the raw (or converting to jpg). You can analyze the data
and
then decide "how to actually expose". I think this is what Pentax may be
doing 
with the "automatic ISO setting". It's like having all the different ISO

negative films in your camera the same time.

(Of course you can have a variable gain amp if you wish to get
"standard"
DSLR behaviour...)

5) With a relatively low gain amplifier and 22 bit A/D (and both having
low 
noise) you will get a really wide exposure latitude. The K10D differs
from the competition in this respect. It is like how negative film
differs from 
slide film.

In theory you will get a very nice package. We'll see how it will
perform
in reality, but I am sure it will do quite nicely. Pentax wouldn't have
used a 22 bits A/D if there wasn't a good reason. 

Antti-Pekka



Antti-Pekka Virjonen

Computec Oy
R&D Turku

www.computec.fi



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It is ingenious! Was: Does this mean what I think it means?

2006-09-14 Thread Antti-Pekka Virjonen
Hi,

I was thinking about the 22 bit A/D converter and about the ISO 
setting last night.

Then it struck me, right into the back of my head... :-)

It is simply ingenious (if this is what Pentax has done):

1) By utilizing a 22 bit A/D you get a wide dynamic range

2) When you have a wide dynamic range on the A/D converter, you don't
have to
use a high gain amplifier stage (to get high ISO sensitivity) but you
can use
a constant (lower) gain low noise (optimized) amplifier.

3) This way you can "choose" the ISO setting after exposure, before
storing 
the image into the raw (or converting to jpg). You can analyze the data
and
then decide "how to actually expose". I think this is what Pentax may be
doing 
with the "automatic ISO setting". It's like having all the different ISO

negative films in your camera the same time.

(Of course you can have a variable gain amp if you wish to get
"standard"
DSLR behaviour...)

5) With a relatively low gain amplifier and 22 bit A/D (and both having
low 
noise) you will get a really wide exposure latitude. The K10D differs
from the competition in this respect. It is like how negative film
differs from 
slide film.

In theory you will get a very nice package. We'll see how it will
perform
in reality, but I am sure it will do quite nicely. Pentax wouldn't have
used a 22 bits A/D if there wasn't a good reason. 

Antti-Pekka



Antti-Pekka Virjonen

Computec Oy
R&D Turku
Fiskarsinkatu 7 D
FIN-20750 Turku Finland

Puh. +358 20 7908 300
GSM +358 500 789 753
Telefax +358 20 7908 319

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Re: Does this mean what I think it means?

2006-09-14 Thread Adam Maas
Patrice LACOUTURE (GMail) wrote:
> Adam Maas a écrit :
> 
>> From the Pentax France Page:
>>
>>Le traitement interne des fichiers RAW permet d'agir sur la taille, la 
>>compression, la balance des blancs, le réglage des ISO (Pentax est le 
>>seul), le ton de l'image, la saturation, la netteté et le contraste.
>>
>>via Babelfish:
>>
>>The internal treatment of files RAW makes it possible to act on the 
>>size, compression, the balance of the white, the adjustment of the ISO 
>>(Pentax is only), the tone of the image, saturation, clearness and contrast.
>>
>>It sounds like ISO adjustment in post is possible with RAW files. That 
>>would be an earth-shaking capability.
>>
>>-Adam
>>
>>
>>  
> 
> Hi,
> 
> French is my mother tongue (as my name suggests), and I can say that the 
> babelfish translation is accurate in saying that it is "possible to 
> *act* on ... the ISO adjustment".
> 
> To my ears this means that the ISO can be somehow (?) set at 
> post-processing.
> 
> How they achieve such a result while storing only the 12bits in the RAW 
> file is still a mystery to me. I wouldn't say so if at least 4 more bits 
> were stored into the RAW.
> 
> Otherwise, with a 12bit RAW, +1 EV push gives roughly 11 useful bits, +4 
> EV (100->1600) gives only 8 useful bits => nothing I can't do with my 
> *ist DS...
> 
> Patrice
> 

My french is passable and that's what I came up with. The DPReview 
Preview indicates that you can set ISO when processing RAW's in-camera, 
after shooting.

-Adam


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Re: Does this mean what I think it means?

2006-09-14 Thread Patrice LACOUTURE (GMail)
Adam Maas a écrit :
>  From the Pentax France Page:
>
> Le traitement interne des fichiers RAW permet d'agir sur la taille, la 
> compression, la balance des blancs, le réglage des ISO (Pentax est le 
> seul), le ton de l'image, la saturation, la netteté et le contraste.
>
> via Babelfish:
>
> The internal treatment of files RAW makes it possible to act on the 
> size, compression, the balance of the white, the adjustment of the ISO 
> (Pentax is only), the tone of the image, saturation, clearness and contrast.
>
> It sounds like ISO adjustment in post is possible with RAW files. That 
> would be an earth-shaking capability.
>
> -Adam
>
>
>   
Hi,

French is my mother tongue (as my name suggests), and I can say that the 
babelfish translation is accurate in saying that it is "possible to 
*act* on ... the ISO adjustment".

To my ears this means that the ISO can be somehow (?) set at 
post-processing.

How they achieve such a result while storing only the 12bits in the RAW 
file is still a mystery to me. I wouldn't say so if at least 4 more bits 
were stored into the RAW.

Otherwise, with a 12bit RAW, +1 EV push gives roughly 11 useful bits, +4 
EV (100->1600) gives only 8 useful bits => nothing I can't do with my 
*ist DS...

Patrice

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Re: Does this mean what I think it means?

2006-09-14 Thread Digital Image Studio
On 14/09/06, Rob Brigham <[EMAIL PROTECTED]> wrote:
> http://www.dpreview.com/articles/PentaxK10D/Images/Captures/TV2006090616253900-01.jpg
>
> This shot which illustrates the in camera RAW processing does indeed suggest 
> setting ISO after the event?  Or are they just misleading by using ISO in the 
> display to mean brightness in general?

Yes, it's a bit confusing.

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RE: Does this mean what I think it means?

2006-09-14 Thread Rob Brigham
http://www.dpreview.com/articles/PentaxK10D/Images/Captures/TV2006090616253900-01.jpg

This shot which illustrates the in camera RAW processing does indeed suggest 
setting ISO after the event?  Or are they just misleading by using ISO in the 
display to mean brightness in general?

Rob

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Adam Maas
Sent: 13 September 2006 21:44
To: Pentax-Discuss Mail List
Subject: Re: Does this mean what I think it means?


What program allows ISO changes during RAW conversion? Exposure yes, ISO no.

-Adam


Dario Bonazza wrote:
> ISO setting during PC conversion is common stuff.
> ISO seting during in-camera conversion is what they claim.
> 
> Dario
> 
> - Original Message -
> From: "Adam Maas" <[EMAIL PROTECTED]>
> To: "Pentax-Discuss Mail List" 
> Sent: Wednesday, September 13, 2006 10:16 PM
> Subject: Re: Does this mean what I think it means?
> 
> 
> Toralf Lund wrote:
> 
>>>From the Pentax France Page:
>>>
>>>Le traitement interne des fichiers RAW permet d'agir sur la taille, 
>>>la compression, la balance des blancs, le réglage des ISO (Pentax est 
>>>le seul), le ton de l'image, la saturation, la netteté et le 
>>>contraste.
>>>
>>>via Babelfish:
>>>
>>>The internal treatment of files RAW makes it possible to act on the 
>>>size, compression, the balance of the white, the adjustment of the 
>>>ISO (Pentax is only), the tone of the image, saturation, clearness 
>>>and contrast.
>>>
>>>It sounds like ISO adjustment in post is possible with RAW files. 
>>>That would be an earth-shaking capability.
>>>
>>
>>Really?
>>
>>I've always been thinking that since the lower few bits in current 
>>high-ISO shots is essentially just noise, you might get output of the 
>>same quality by shooting at a lower ISO (and under-exposing), then 
>>"multiplying up" the pixels from the RAW file...
>>
>>But what this sound like to me (who doesn't speak much French, 
>>either), is merely that details on the ISO setting that already was 
>>applied, will be stored in the tags of the file. (And maybe ISO 
>>adjustment will be a somewhat more complex operation in this camera?)
>>
>>- Toralf
>>
> 
> 
> However, that would not be a 'Pentax Only' feature, which they are 
> claiming. ISO adjustment in post would be.
> 
> -Adam
> 
> 
> 



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Re: Does this mean what I think it means?

2006-09-14 Thread graywolf
Basically, all pushing, or pulling, is is moving the exposure up and 
down the sensometric curve and adjusting the contrast with processing. 
RAW converter seems to do about the same thing.

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Paul Stenquist wrote:
> Push/pull processing is extremely limited. With most film, it's  
> relatively ineffective and quickly causes degradation.
> Paul
> On Sep 13, 2006, at 5:00 PM, Brendan MacRae wrote:
> 
>>
>> --- Adam Maas <[EMAIL PROTECTED]> wrote:
>>
>>
>>> It sounds like ISO adjustment in post is possible
>>> with RAW files. That
>>> would be an earth-shaking capability.
>>>
>>> -Adam
>>>
>> Except that I can do that everyday with film;
>> push/pull processing. My earth ain't really shakin
>> over here yet.
>>
>> -Brendan
>>> -- 
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Re: Does this mean what I think it means?

2006-09-14 Thread Toralf Lund

>> I think push processing is a very good analogy. You can't strictly
>> speaking change the ISO on a digital camera - the sensor has a fixed
>> sensitivity. ...
>> 
>
> ... at a specified voltage input/output level. If you change the  
> voltage levels, you are changing the response curve and thus the ISO.  
> Changing ISO is not the same as multiplying the pixel values from a  
> sensor with a fixed voltage level, which is basically what the  
> exposure compensation slider in a RAW converter does unless the  
> programmer who designed it includes additional processing of  
> differential values.
>   
But doesn't the ISO setting in the camera amplify the voltages after the 
data is read from the sensor? I really can't see how this is different 
from multiplying the pixel values. Or it's different, as in one case you 
multiply the values before they are converted to digital, in the other 
after - but in principle there's not much difference, and the final 
image quality ought to be the same. Unless  the A/D that chops off real 
data in the low end when the gain is 1 (i.e. when the max value of the 
A/D matches saturation of the sensor), but I gather that it doesn't. The 
theoretical extra bits that get thrown away, are assumed to contain only 
random variation caused by noise.

Also, ISO for a digital sensor is apparently defined in terms of 
signal-to-noise ratio, and that obviously doesn't change when you 
multiply the signal.

- Toralf


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Re: Does this mean what I think it means?

2006-09-13 Thread Brendan MacRae
Fair enough...except some films are designed
specifically to "pushed around" .

What about in digital? Won't an increase in the ISO
later on still "degrade" the image (more noise)?

-Brendan
--- Paul Stenquist <[EMAIL PROTECTED]> wrote:

> Push/pull processing is extremely limited. With most
> film, it's  
> relatively ineffective and quickly causes
> degradation.
> Paul
> On Sep 13, 2006, at 5:00 PM, Brendan MacRae wrote:
> 
> >
> >
> > --- Adam Maas <[EMAIL PROTECTED]> wrote:
> >
> >
> >> It sounds like ISO adjustment in post is possible
> >> with RAW files. That
> >> would be an earth-shaking capability.
> >>
> >> -Adam
> >>
> >
> > Except that I can do that everyday with film;
> > push/pull processing. My earth ain't really shakin
> > over here yet.
> >
> > -Brendan
> >>
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> >
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Re: Does this mean what I think it means?

2006-09-13 Thread Ryan Brooks
Adam Maas wrote:
> No, you're changing the conversion curve and levels. ISO is normally set 
>   at the ADC stage.
>
>   
No, it's set by the amplifier(s) before the A/D.

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Re: Does this mean what I think it means?

2006-09-13 Thread Paul Stenquist
Push/pull processing is extremely limited. With most film, it's  
relatively ineffective and quickly causes degradation.
Paul
On Sep 13, 2006, at 5:00 PM, Brendan MacRae wrote:

>
>
> --- Adam Maas <[EMAIL PROTECTED]> wrote:
>
>
>> It sounds like ISO adjustment in post is possible
>> with RAW files. That
>> would be an earth-shaking capability.
>>
>> -Adam
>>
>
> Except that I can do that everyday with film;
> push/pull processing. My earth ain't really shakin
> over here yet.
>
> -Brendan
>>
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>
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Re: Does this mean what I think it means?

2006-09-13 Thread Godfrey DiGiorgi

On Sep 13, 2006, at 2:55 PM, Toralf Lund wrote:

> I think push processing is a very good analogy. You can't strictly
> speaking change the ISO on a digital camera - the sensor has a fixed
> sensitivity. ...

... at a specified voltage input/output level. If you change the  
voltage levels, you are changing the response curve and thus the ISO.  
Changing ISO is not the same as multiplying the pixel values from a  
sensor with a fixed voltage level, which is basically what the  
exposure compensation slider in a RAW converter does unless the  
programmer who designed it includes additional processing of  
differential values.

Given a reference film emulsion and density curve with a given  
developer, push processing with the same developer and emulsion means  
reducing the exposure so as not to block up highlights while  
extending the development. This changes the gamma curve and allows  
you to treat overall exposure as a rise in sensitivity, but you're  
shortening the dynamic range of the capture.

It is directly analogous to modifying the voltage environment of the  
sensor and has similar results except that the digital sensor, within  
its range of acceptable voltages, can be more pliant about change and  
more controllable about side effects. With film, you're locked into  
the inflexible world of chemical reactions and can't apply  
mathematical transformations to correct a problem which develops.

Godfrey


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Re: Does this mean what I think it means?

2006-09-13 Thread Toralf Lund
Dario Bonazza wrote:
> I keep thinking in photographic terms. In my understanding, exposure depends 
> on:
>
> 1 - Subject's brightness
> 2 - Lens aperture
> 3 - Shutter speed
> 4 - Film/Sensor sensitivity
>
> Sure you cannot change 1/2/3 during processing, but you can change 4 
> (sensitivity). OK, Rawshooter calls it Exposure Compensation, not 
> Sensitivity. But since you cannot change 1/2/3...
>
> Please slide that Exposure Compensation slider right or left and see what 
> happens to the histogram. You can even recover clipping, isn't that a 
> sensitivity change? OK, let's call it software sensitivity, as opposed to 
> the hardware sensitivity at ADC stage, but we can also call it push 
> processing... Push processing can change ISO, can't it?
>   
I think push processing is a very good analogy. You can't strictly 
speaking change the ISO on a digital camera - the sensor has a fixed 
sensitivity. You can only do exposure compensation and/or *emulate* a 
different ISO. It's the same thing with push processing, isn't it? It 
doesn't *really* change the ISO of the film, but simulates the 
appearance of exposures on a higher ISO film?

Maybe digital sensors respond to push processing in a better way than 
most film, though...

- Toralf

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Re: Does this mean what I think it means?

2006-09-13 Thread Dario Bonazza
I keep thinking in photographic terms. In my understanding, exposure depends 
on:

1 - Subject's brightness
2 - Lens aperture
3 - Shutter speed
4 - Film/Sensor sensitivity

Sure you cannot change 1/2/3 during processing, but you can change 4 
(sensitivity). OK, Rawshooter calls it Exposure Compensation, not 
Sensitivity. But since you cannot change 1/2/3...

Please slide that Exposure Compensation slider right or left and see what 
happens to the histogram. You can even recover clipping, isn't that a 
sensitivity change? OK, let's call it software sensitivity, as opposed to 
the hardware sensitivity at ADC stage, but we can also call it push 
processing... Push processing can change ISO, can't it?

So at the end the K10D is (among many other things) a reincarnation of a 
Polaroid camera capable of controlled push processing.

Or at least this is how I see it. You can well see it as levels and curves.

Dario

- Original Message - 
From: "Adam Maas" <[EMAIL PROTECTED]>
To: "Pentax-Discuss Mail List" 
Sent: Wednesday, September 13, 2006 11:01 PM
Subject: Re: Does this mean what I think it means?


No, you're changing the conversion curve and levels. ISO is normally set
  at the ADC stage.

-Adam

Dario Bonazza wrote:
> Since a PC is not a camera, what would you adjust when you adjust exposure
> during RAW conversion?
> Sure you change neither aperture nor shutter speed! I've always thought 
> you
> change ISO sensitivity.
>
> I can be wrong, but I bet that such a feature is what Pentax is claiming
> here. If so, who cares of in-camera RAW conversion?
>
> Dario
>
> - Original Message - 
> From: "Adam Maas" <[EMAIL PROTECTED]>
> To: "Pentax-Discuss Mail List" 
> Sent: Wednesday, September 13, 2006 10:43 PM
> Subject: Re: Does this mean what I think it means?
>
>
> What program allows ISO changes during RAW conversion? Exposure yes, ISO 
> no.
>
> -Adam
>
>
> Dario Bonazza wrote:
>
>>ISO setting during PC conversion is common stuff.
>>ISO seting during in-camera conversion is what they claim.
>>
>>Dario
>>
>>- Original Message - 
>>From: "Adam Maas" <[EMAIL PROTECTED]>
>>To: "Pentax-Discuss Mail List" 
>>Sent: Wednesday, September 13, 2006 10:16 PM
>>Subject: Re: Does this mean what I think it means?
>>
>>
>>Toralf Lund wrote:
>>
>>
>>>>From the Pentax France Page:
>>>
>>>>Le traitement interne des fichiers RAW permet d'agir sur la taille, la
>>>>compression, la balance des blancs, le réglage des ISO (Pentax est le
>>>>seul), le ton de l'image, la saturation, la netteté et le contraste.
>>>>
>>>>via Babelfish:
>>>>
>>>>The internal treatment of files RAW makes it possible to act on the
>>>>size, compression, the balance of the white, the adjustment of the ISO
>>>>(Pentax is only), the tone of the image, saturation, clearness and
>>>>contrast.
>>>>
>>>>It sounds like ISO adjustment in post is possible with RAW files. That
>>>>would be an earth-shaking capability.
>>>>
>>>
>>>Really?
>>>
>>>I've always been thinking that since the lower few bits in current
>>>high-ISO shots is essentially just noise, you might get output of the
>>>same quality by shooting at a lower ISO (and under-exposing), then
>>>"multiplying up" the pixels from the RAW file...
>>>
>>>But what this sound like to me (who doesn't speak much French, either),
>>>is merely that details on the ISO setting that already was applied, will
>>>be stored in the tags of the file. (And maybe ISO adjustment will be a
>>>somewhat more complex operation in this camera?)
>>>
>>>- Toralf
>>>
>>
>>
>>However, that would not be a 'Pentax Only' feature, which they are
>>claiming. ISO adjustment in post would be.
>>
>>-Adam
>>
>>
>>
>
>
>
>



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Re: Does this mean what I think it means?

2006-09-13 Thread Toralf Lund
Adam Maas wrote:
> No, you're changing the conversion curve and levels. ISO is normally set 
>   at the ADC stage.
>   
You emulate a different ISO value by modifying the signal/pixel level in 
both cases, it's no more (or less) an ISO setting just because you do it 
in the analogue domain.

- Toralf


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Re: Does this mean what I think it means?

2006-09-13 Thread Adam Maas
No, you're changing the conversion curve and levels. ISO is normally set 
  at the ADC stage.

-Adam

Dario Bonazza wrote:
> Since a PC is not a camera, what would you adjust when you adjust exposure 
> during RAW conversion?
> Sure you change neither aperture nor shutter speed! I've always thought you 
> change ISO sensitivity.
> 
> I can be wrong, but I bet that such a feature is what Pentax is claiming 
> here. If so, who cares of in-camera RAW conversion?
> 
> Dario
> 
> - Original Message - 
> From: "Adam Maas" <[EMAIL PROTECTED]>
> To: "Pentax-Discuss Mail List" 
> Sent: Wednesday, September 13, 2006 10:43 PM
> Subject: Re: Does this mean what I think it means?
> 
> 
> What program allows ISO changes during RAW conversion? Exposure yes, ISO no.
> 
> -Adam
> 
> 
> Dario Bonazza wrote:
> 
>>ISO setting during PC conversion is common stuff.
>>ISO seting during in-camera conversion is what they claim.
>>
>>Dario
>>
>>- Original Message ----- 
>>From: "Adam Maas" <[EMAIL PROTECTED]>
>>To: "Pentax-Discuss Mail List" 
>>Sent: Wednesday, September 13, 2006 10:16 PM
>>Subject: Re: Does this mean what I think it means?
>>
>>
>>Toralf Lund wrote:
>>
>>
>>>>From the Pentax France Page:
>>>
>>>>Le traitement interne des fichiers RAW permet d'agir sur la taille, la
>>>>compression, la balance des blancs, le réglage des ISO (Pentax est le
>>>>seul), le ton de l'image, la saturation, la netteté et le contraste.
>>>>
>>>>via Babelfish:
>>>>
>>>>The internal treatment of files RAW makes it possible to act on the
>>>>size, compression, the balance of the white, the adjustment of the ISO
>>>>(Pentax is only), the tone of the image, saturation, clearness and
>>>>contrast.
>>>>
>>>>It sounds like ISO adjustment in post is possible with RAW files. That
>>>>would be an earth-shaking capability.
>>>>
>>>
>>>Really?
>>>
>>>I've always been thinking that since the lower few bits in current
>>>high-ISO shots is essentially just noise, you might get output of the
>>>same quality by shooting at a lower ISO (and under-exposing), then
>>>"multiplying up" the pixels from the RAW file...
>>>
>>>But what this sound like to me (who doesn't speak much French, either),
>>>is merely that details on the ISO setting that already was applied, will
>>>be stored in the tags of the file. (And maybe ISO adjustment will be a
>>>somewhat more complex operation in this camera?)
>>>
>>>- Toralf
>>>
>>
>>
>>However, that would not be a 'Pentax Only' feature, which they are
>>claiming. ISO adjustment in post would be.
>>
>>-Adam
>>
>>
>>
> 
> 
> 
> 



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Re: Does this mean what I think it means?

2006-09-13 Thread Toralf Lund

> ISO setting during PC conversion is common stuff.
> ISO seting during in-camera conversion is what they claim.
>   
That's what I thought. Except I posted something here before thinking... 
I do know some French. Not much. A little less than that actually...

Like I said earlier, in other cameras, the pixel data is read from the 
sensor, then passed though a gain stage that will amplify the signal 
according to the ISO setting, then converted to 12-bit digital, then fed 
into an image processor that does further work on the data. Or that's 
how I *think* it works.

On the K10D, the data will probably be fed directly from the sensor into 
a 22-bit A/D, then to a more advanced, 22-bit image processor that also 
does the ISO adjustment. Only in the far end of that processor is it 
converted to 12 (or a few more) bits...

- Toralf



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Re: Does this mean what I think it means?

2006-09-13 Thread Brendan MacRae


--- Adam Maas <[EMAIL PROTECTED]> wrote:


> It sounds like ISO adjustment in post is possible
> with RAW files. That 
> would be an earth-shaking capability.
> 
> -Adam
> 

Except that I can do that everyday with film;
push/pull processing. My earth ain't really shakin
over here yet.

-Brendan
> 
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Re: Does this mean what I think it means?

2006-09-13 Thread Dario Bonazza
Since a PC is not a camera, what would you adjust when you adjust exposure 
during RAW conversion?
Sure you change neither aperture nor shutter speed! I've always thought you 
change ISO sensitivity.

I can be wrong, but I bet that such a feature is what Pentax is claiming 
here. If so, who cares of in-camera RAW conversion?

Dario

- Original Message - 
From: "Adam Maas" <[EMAIL PROTECTED]>
To: "Pentax-Discuss Mail List" 
Sent: Wednesday, September 13, 2006 10:43 PM
Subject: Re: Does this mean what I think it means?


What program allows ISO changes during RAW conversion? Exposure yes, ISO no.

-Adam


Dario Bonazza wrote:
> ISO setting during PC conversion is common stuff.
> ISO seting during in-camera conversion is what they claim.
>
> Dario
>
> - Original Message - 
> From: "Adam Maas" <[EMAIL PROTECTED]>
> To: "Pentax-Discuss Mail List" 
> Sent: Wednesday, September 13, 2006 10:16 PM
> Subject: Re: Does this mean what I think it means?
>
>
> Toralf Lund wrote:
>
>>>From the Pentax France Page:
>>>
>>>Le traitement interne des fichiers RAW permet d'agir sur la taille, la
>>>compression, la balance des blancs, le réglage des ISO (Pentax est le
>>>seul), le ton de l'image, la saturation, la netteté et le contraste.
>>>
>>>via Babelfish:
>>>
>>>The internal treatment of files RAW makes it possible to act on the
>>>size, compression, the balance of the white, the adjustment of the ISO
>>>(Pentax is only), the tone of the image, saturation, clearness and
>>>contrast.
>>>
>>>It sounds like ISO adjustment in post is possible with RAW files. That
>>>would be an earth-shaking capability.
>>>
>>
>>Really?
>>
>>I've always been thinking that since the lower few bits in current
>>high-ISO shots is essentially just noise, you might get output of the
>>same quality by shooting at a lower ISO (and under-exposing), then
>>"multiplying up" the pixels from the RAW file...
>>
>>But what this sound like to me (who doesn't speak much French, either),
>>is merely that details on the ISO setting that already was applied, will
>>be stored in the tags of the file. (And maybe ISO adjustment will be a
>>somewhat more complex operation in this camera?)
>>
>>- Toralf
>>
>
>
> However, that would not be a 'Pentax Only' feature, which they are
> claiming. ISO adjustment in post would be.
>
> -Adam
>
>
>



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Re: Does this mean what I think it means?

2006-09-13 Thread Toralf Lund

>> But what this sound like to me (who doesn't speak much French, either), 
>> is merely that details on the ISO setting that already was applied, will 
>> be stored in the tags of the file. (And maybe ISO adjustment will be a 
>> somewhat more complex operation in this camera?)
>>
>> - Toralf
>>
>> 
>
> However, that would not be a 'Pentax Only' feature, which they are 
> claiming. ISO adjustment in post would be.
>   
I have a third theory, too. (Let me post it really fast before someone 
who actually speak the language comes along):

What it says is simply that the ISO setting is applied by the "raw" 
image processor - and not by a pre-A/D gain stage. I've already 
speculated about this once today ;-)

- Toralf



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Re: Does this mean what I think it means?

2006-09-13 Thread Adam Maas
What program allows ISO changes during RAW conversion? Exposure yes, ISO no.

-Adam


Dario Bonazza wrote:
> ISO setting during PC conversion is common stuff.
> ISO seting during in-camera conversion is what they claim.
> 
> Dario
> 
> - Original Message - 
> From: "Adam Maas" <[EMAIL PROTECTED]>
> To: "Pentax-Discuss Mail List" 
> Sent: Wednesday, September 13, 2006 10:16 PM
> Subject: Re: Does this mean what I think it means?
> 
> 
> Toralf Lund wrote:
> 
>>>From the Pentax France Page:
>>>
>>>Le traitement interne des fichiers RAW permet d'agir sur la taille, la
>>>compression, la balance des blancs, le réglage des ISO (Pentax est le
>>>seul), le ton de l'image, la saturation, la netteté et le contraste.
>>>
>>>via Babelfish:
>>>
>>>The internal treatment of files RAW makes it possible to act on the
>>>size, compression, the balance of the white, the adjustment of the ISO
>>>(Pentax is only), the tone of the image, saturation, clearness and 
>>>contrast.
>>>
>>>It sounds like ISO adjustment in post is possible with RAW files. That
>>>would be an earth-shaking capability.
>>>
>>
>>Really?
>>
>>I've always been thinking that since the lower few bits in current
>>high-ISO shots is essentially just noise, you might get output of the
>>same quality by shooting at a lower ISO (and under-exposing), then
>>"multiplying up" the pixels from the RAW file...
>>
>>But what this sound like to me (who doesn't speak much French, either),
>>is merely that details on the ISO setting that already was applied, will
>>be stored in the tags of the file. (And maybe ISO adjustment will be a
>>somewhat more complex operation in this camera?)
>>
>>- Toralf
>>
> 
> 
> However, that would not be a 'Pentax Only' feature, which they are
> claiming. ISO adjustment in post would be.
> 
> -Adam
> 
> 
> 



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Re: Does this mean what I think it means?

2006-09-13 Thread Dario Bonazza
ISO setting during PC conversion is common stuff.
ISO seting during in-camera conversion is what they claim.

Dario

- Original Message - 
From: "Adam Maas" <[EMAIL PROTECTED]>
To: "Pentax-Discuss Mail List" 
Sent: Wednesday, September 13, 2006 10:16 PM
Subject: Re: Does this mean what I think it means?


Toralf Lund wrote:
>> From the Pentax France Page:
>>
>>Le traitement interne des fichiers RAW permet d'agir sur la taille, la
>>compression, la balance des blancs, le réglage des ISO (Pentax est le
>>seul), le ton de l'image, la saturation, la netteté et le contraste.
>>
>>via Babelfish:
>>
>>The internal treatment of files RAW makes it possible to act on the
>>size, compression, the balance of the white, the adjustment of the ISO
>>(Pentax is only), the tone of the image, saturation, clearness and 
>>contrast.
>>
>>It sounds like ISO adjustment in post is possible with RAW files. That
>>would be an earth-shaking capability.
>>
>
> Really?
>
> I've always been thinking that since the lower few bits in current
> high-ISO shots is essentially just noise, you might get output of the
> same quality by shooting at a lower ISO (and under-exposing), then
> "multiplying up" the pixels from the RAW file...
>
> But what this sound like to me (who doesn't speak much French, either),
> is merely that details on the ISO setting that already was applied, will
> be stored in the tags of the file. (And maybe ISO adjustment will be a
> somewhat more complex operation in this camera?)
>
> - Toralf
>

However, that would not be a 'Pentax Only' feature, which they are
claiming. ISO adjustment in post would be.

-Adam



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Re: Does this mean what I think it means?

2006-09-13 Thread Toralf Lund
Toralf Lund wrote:
>>  From the Pentax France Page:
>>
>> Le traitement interne des fichiers RAW permet d'agir sur la taille, la 
>> compression, la balance des blancs, le réglage des ISO (Pentax est le 
>> seul), le ton de l'image, la saturation, la netteté et le contraste. [ ... ]
>>
>> 
>
> But what this sound like to me (who doesn't speak much French, either), 
> is merely that details on the ISO setting that already was applied, will 
> be stored in the tags of the file.
>   
Or perhaps not. After reading it again, I'm wondering if not what it 
says is that the camera's ISO adjustment process may be configured somehow.

- Toralf


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Re: Does this mean what I think it means?

2006-09-13 Thread Adam Maas
Toralf Lund wrote:
>> From the Pentax France Page:
>>
>>Le traitement interne des fichiers RAW permet d'agir sur la taille, la 
>>compression, la balance des blancs, le réglage des ISO (Pentax est le 
>>seul), le ton de l'image, la saturation, la netteté et le contraste.
>>
>>via Babelfish:
>>
>>The internal treatment of files RAW makes it possible to act on the 
>>size, compression, the balance of the white, the adjustment of the ISO 
>>(Pentax is only), the tone of the image, saturation, clearness and contrast.
>>
>>It sounds like ISO adjustment in post is possible with RAW files. That 
>>would be an earth-shaking capability.
>>  
> 
> Really?
> 
> I've always been thinking that since the lower few bits in current 
> high-ISO shots is essentially just noise, you might get output of the 
> same quality by shooting at a lower ISO (and under-exposing), then 
> "multiplying up" the pixels from the RAW file...
> 
> But what this sound like to me (who doesn't speak much French, either), 
> is merely that details on the ISO setting that already was applied, will 
> be stored in the tags of the file. (And maybe ISO adjustment will be a 
> somewhat more complex operation in this camera?)
> 
> - Toralf
> 

However, that would not be a 'Pentax Only' feature, which they are 
claiming. ISO adjustment in post would be.

-Adam



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Re: Does this mean what I think it means?

2006-09-13 Thread Toralf Lund

>  From the Pentax France Page:
>
> Le traitement interne des fichiers RAW permet d'agir sur la taille, la 
> compression, la balance des blancs, le réglage des ISO (Pentax est le 
> seul), le ton de l'image, la saturation, la netteté et le contraste.
>
> via Babelfish:
>
> The internal treatment of files RAW makes it possible to act on the 
> size, compression, the balance of the white, the adjustment of the ISO 
> (Pentax is only), the tone of the image, saturation, clearness and contrast.
>
> It sounds like ISO adjustment in post is possible with RAW files. That 
> would be an earth-shaking capability.
>   
Really?

I've always been thinking that since the lower few bits in current 
high-ISO shots is essentially just noise, you might get output of the 
same quality by shooting at a lower ISO (and under-exposing), then 
"multiplying up" the pixels from the RAW file...

But what this sound like to me (who doesn't speak much French, either), 
is merely that details on the ISO setting that already was applied, will 
be stored in the tags of the file. (And maybe ISO adjustment will be a 
somewhat more complex operation in this camera?)

- Toralf



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Does this mean what I think it means?

2006-09-13 Thread Adam Maas
 From the Pentax France Page:

Le traitement interne des fichiers RAW permet d'agir sur la taille, la 
compression, la balance des blancs, le réglage des ISO (Pentax est le 
seul), le ton de l'image, la saturation, la netteté et le contraste.

via Babelfish:

The internal treatment of files RAW makes it possible to act on the 
size, compression, the balance of the white, the adjustment of the ISO 
(Pentax is only), the tone of the image, saturation, clearness and contrast.

It sounds like ISO adjustment in post is possible with RAW files. That 
would be an earth-shaking capability.

-Adam


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