A Photography forum. PhotoBanter.com

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » PhotoBanter.com forum » General Photography » In The Darkroom
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

dynamic range and exposure latitude?



 
 
Thread Tools Display Modes
  #1  
Old February 27th 14, 04:08 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

I don't have access to current professional equipment, software, or
media, so I will rely on feedback and past experience, and the criticism
thereof

video sensor and filtration device color space assumptions face a
complexity with other output than CRT (LCD, LED, Plasma, OLED, and I
read better LCD is on the way)

ICC solution to dynamic range is based on ProPhoto RGB according to
wikipedia (there is also Adobe RGB, and Wide Gamut RGB, on wikipedia)
http://en.wikipedia.org/wiki/ProPhoto_RGB
implemented in RIMM,ERIMM, and ROMM
http://www.color.org
http://www.color.org/chardata/rgb/rimmrgb.xalter
http://www.color.org/chardata/rgb/erimmrgb.xalter
http://www.color.org/romm.xalter

ICC does not reveal the assumed film or idealistic/standard film used in
ProPhoto RGB

ProPhotoRGB chromaticity coordinates are linear with CIE chromaticity
coordinates

CIE tone is linear with light (L,Y,B,V) or linear with lightness (L*)

film due to chemical considerations of activity and exhaustion and
design for dynamic range treatments, has a toe and shoulder modeled and
designed using a quadratic as opposed to linear contrast, such as a
rational quadratic which does not bend over the toe or shoulder

since film contrast is not linear, some calculations must be performed
to have it linear

ICC does not reveal such considerations

Kodak designed ProPhoto RGB, probably in light of sRGB workflows being
accepted, as opposed to using an ideal digital camera and an ideal
digital projector as the RIMM,ERIMM, ROMM (additive color used in
displays has more dynamic range than subtractive colors used prints)

one Kodak implementation I know called Premier (a system of scanning
film, manipulating and editing film, and outputting film) used a
linearized film assumption

I believe this linearization was achieved by unbuilding the rationall
quadratic contrast, and some form of interimage of an Ektachrome film of
the time, be it spectral sensitivity interimage or chemical process
interimage, I don't really know which one or if both were used, I heard
it once but I forget

some use cases would prefer color matching as opposed to appearance
matching and would not use RIMM,ERIMM, ROMM, they would use CIE RGB

but most use cases involve a viewing and acceptance of an image, even if
it just a consumer looking at something and saying it is "good enough"

what is ProPhotoRGB? Is it a negative with exposure latitude suiting it
to ERIMM? if so this could complement many hybrid workflows where
transparency film output is used or copied in an analog fashion

in fact you could design a color negative film to be scanned,
manipulated, output, and projected with ICC color management

you unbuild the non-linearity and crosstalk of the film as long as it's
image dyes chromaticity coordinates result in something close enough to
linear with CIE chromaticity coordinates, making it easier to scan on a
scanner whose exposure, filtration and sensitivity are designed to be
linear with CIE chromaticity coordinates

manipulation algorithms relative to CIE are widely available, but you
could add analog editing, and hybrid algorithms to the mix

you can design a projector (exposure, filtration) in a digital
environment, with the right analog and hybrid manipulation
consideration, to display a color negative instead of using a
transparency intermediate

such a projector design leads to an easy film recorder design

same with monitor design ...

is film dead? should you snip most of the above? are professional
digital capture, manipulation and output already exceeding color
negatives for dynamic range and exposure latitude? even considering push
and pull chemical processing?

then why not a digital RIMM,ERIMM and ROMM?

the ICC site says color managed workflows have not taken hold in
digital, I read once, is this because of sRGB(video) and
ProPhotoRGB(film) workflow interference?

are digital RIMM,ERIMM and ROMM to far outside of CIE eye based
considerations? then why not use CIE RGB for the RIMM,ERIMM, and ROMM

probably the best bet considering printed page is not dead and
Perceptual Reference Medium (PRM) can be used in ICC
http://www.color.org/v4_prmg.xalter
is to give customers choices for their use cases of what reference suits
them

things like lighting, surround, flare, viewing angle, measurement
considerations likewise could all be incorporated

a little more education,, maybe too much for "good enough" color,
especially since "more attractive color" exists

some form of device independent "accurate" color and appearance must be
a starting point?

for consumers, white balance might not be the only scene balance that is
used, you could use analog and hybrid models to get to the "more
attractive color" achieved in consumer films like "pop" saturation

if you think I am a troll, give me a entry level imaging systems job in
my area and I will have to keep my ideas to myself, I don't quite
qualify for standards or open systems work, so here I am on usenet,
wikipedia, wiktionary and the web

I have an undergrad honors degree in ChemE with minors in polymer
science and math (forget most of this)
I know a little MATLAB and SAS
I know basic programming on punch cards and punch card readers
I know Fortran data flow programming
I know modular Pascal data flow programming
I know a little C
I know a little object oriented (OO) architecture/design
I know a little C++ OO programming
I know the basics of java systems and OO programming
I just can't get abstract IDEs like netbeans or operating system
required libraries, out of my head to write a complex program
maybe I should spend more time learning java than talking on usenet

--
Dale
  #2  
Old February 27th 14, 04:58 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
isw
external usenet poster
 
Posts: 212
Default dynamic range and exposure latitude?

In article ,
Dale wrote:

you can design a projector (exposure, filtration) in a digital
environment, with the right analog and hybrid manipulation
consideration, to display a color negative instead of using a
transparency intermediate

such a projector design leads to an easy film recorder design


I did some film recorder development about 30 years ago. I don't think
"easy" is a term I'd use in conjunction with their design (assuming you
wanted any sort of decent quality, anyhow).

Isaac
  #3  
Old February 27th 14, 05:03 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

On 02/26/2014 11:08 PM, Dale wrote:

one Kodak implementation I know called Premier (a system of scanning
film, manipulating and editing film, and outputting film) used a
linearized film assumption


sort of like applying "printing density" if you know what that is, maybe
this will explain
http://en.wikipedia.org/wiki/Cineon

--
Dale
  #4  
Old February 27th 14, 05:04 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

On 02/26/2014 11:08 PM, Dale wrote:
if you think I am a troll, give me a entry level imaging systems job in
my area and I will have to keep my ideas to myself, I don't quite
qualify for standards or open systems work, so here I am on usenet,
wikipedia, wiktionary and the web

I have an undergrad honors degree in ChemE with minors in polymer
science and math (forget most of this)
I know a little MATLAB and SAS
I know basic programming on punch cards and punch card readers
I know Fortran data flow programming
I know modular Pascal data flow programming
I know a little C
I know a little object oriented (OO) architecture/design
I know a little C++ OO programming
I know the basics of java systems and OO programming
I just can't get abstract IDEs like netbeans or operating system
required libraries, out of my head to write a complex program
maybe I should spend more time learning java than talking on usenet


9 years on the job imaging R&D at Kodak
17 years reflection and internet/wikipedia, etc. study

--
Dale
  #5  
Old February 27th 14, 06:16 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

On 02/26/2014 11:58 PM, isw wrote:
In article ,
Dale wrote:

you can design a projector (exposure, filtration) in a digital
environment, with the right analog and hybrid manipulation
consideration, to display a color negative instead of using a
transparency intermediate

such a projector design leads to an easy film recorder design


I did some film recorder development about 30 years ago. I don't think
"easy" is a term I'd use in conjunction with their design (assuming you
wanted any sort of decent quality, anyhow).

Isaac


I'm just talking to myself while I write and share my thoughts,
sometimes I'm wrong, I even have two kook awards on alt.usenet.kooks
from my political, philosophical, psychological,, sociological and
religious viewpoints on other groups, feel free to nominate me for
another kook award, I am not a troll, I am a kook

never did any hardware development,

I did paper development, process development, hybrid systems development

no research assignments, an engineer not a scientist, but I dabbled in
science when I could

I'd like to think my mainly applications work that could have led up to
system work at Kodak R&D for 9 years contributed to a little system
development, or so I was complemented sometimes

I had a good boss that told me to specialize and not try to understand
everything about imaging, there are few generals in imaging standards,
people like David McDowell

you really have to read into my rudimentary explanations, somethings are
outright wrong no doubt, just putting some pieces together in 17 years
of reflection and internet

--
Dale
  #6  
Old February 27th 14, 06:22 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

On 02/26/2014 11:08 PM, Dale wrote:
maybe I should spend more time learning java than talking on usenet


and Software as a Service (SaaS) Cloud Computing

java requires a license to distribute development, so C or C++ on my
linux system is where I will look at metafile (vector/raster
combinations) imaging stuff I think

a specialization, better suited to me than trying to be a general of the
whole imaging industry with my limited experience

--
Dale
  #7  
Old March 1st 14, 12:17 PM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

On 03/01/2014 06:08 AM, Jeroen wrote:
Hey Dale,

You will be happy to learn that the movie and TV industries
are collaborating on new standards for any or all of:
- high dynamic range (luminance between 10^-4 and 10^4 nit)
- wide color gamut (the entire visible spectrum, and more)
- higher static resolution (4k x 2k, 8k x 4k), and
- higher frame rates (60, 120, maybe 240 fps).


mpeg or ICC or ?



About adapting images to a limited dynamic range or color
gamut, that is a manual artistic process called "color
grading". It is an illusion that this would be left to the
built-in properties of a chemical or electronic system.


if film workflows exist long enough, I thinkk you could design a hbrid
system with ONE film, ONE chemical process, and a scanner, writer, and
projector best suited to such film



The best that the industry can provide is a transparent
standard for carrying the images to the viewers, the rest
is still up to the creative people of "Hollywood".


I think the film could be negative,, higher exposure latitude, but you
would have to have a scanner, writer, projector designed for that film,
this does mean approvals/edits would have to be viewing "soft" display
or display(output) approvals

a digital projector could receive the right codes values from the right
ICC color management system

after talking about hybrid systems for awhile here I decided to visit
Kodak's website and see what analog and hybrid products they had
http"//www.kodak.com

looks like consumer is only digital I think
no sight of the portrait market I think
commercial products are all digital I think

but there is a huge catalog of motion picture film, chemistry, filters, etc.
http://motion.kodak.com/motion/index.htm
http://motion.kodak.com/motion/Produ...tion/index.htm

they claim video clips highlights, there is no "toe" in digital
contrast, and small gamut sRGB doesn't help, I see dress white shirts
clipped on my CRT television

they don't mention spectral reflectances, wide gamut RIMM, ERIMM, ROMM,
like ProPhoto RGB don't even capture all of the eye's colors, let alone
the clipping of a surface color when wide spectral reflectances hit it,
this was a consideration with CCD scanning when I worked at Kodak R&D 17
years ago
http://en.wikipedia.org/wiki/ProPhoto_RGB
http://www.color.org/search.xalter?q=rimm&go.x=0&go.y=0
http://www.color.org/search.xalter?q...&go.x=0&go.y=0
http://www.color.org/search.xalter?q=romm&go.x=0&go.y=0

are people still using film for quality?
does film still have a dynamic range and exposure latitude advantage?
(film contrast is not linear like gamma, it has a toe and shoulder due
to chemical activity and exhaustion and optimization thereof, that
curves off highlights and shadows leaving them reproducible

do people still prefer the "look and feel" of some films like B&W?
these "looks and feels" could be put into abstract ICC profiles with the
right film characteristic information

the right film characterization information is not even provided in the
standardization of ProPhoto RGB as ICC's RIMM,ERIMM, and ROMM
http://www.color.org

with the right film characterization information, one could develop a
hybrid ICC system to suit Kodak's motion picture catalog, if there is
time before digital capture, manipulation and projection replace the
industry's establishment investment

such a hybrid system, and the abstract ICC profiles mentioned above,
could reduce Kodak's catalog to ONE input/output film and ONE chemistry,
if such film was co-optimized with the right hybrid scanning,
manipulation, and output

if film still has a dynamic range and exposure latitude advantage,
perhaps as it's standardization as RIMM, ERIMM, and ROMM, a color
negative could be scanned, output and projected with the right ICC
processing using film and equipment characterization information

a film program cost around $5million when I was at Kodak.
I have no idea how much or fast an equipment program would take

but at least Kodak should share their film characterization information
for optimization in existing information, use in existing digital
manipulation and incorporation in abstract ICC profiles, this would
allow more quality for the film, unless somehow you say they are
operating on a price only paradigm

included below is a list of some necessary film characterization
information, an expert could add to or correct this list

both empirical (easy way) and mechanistic (hard way) are supported
mathematically by the ICC, but you could do your own system
http:/www.color.org

empirical characterization entails printing an equipment code value
target to the "calibrated" equipment and relating it mathematically as a
profile to the color of the profile connection space, usually cubic, a
three dimensional profile for 3 colorant mediums, I know there are at
least or there once was 4 colorant mediums from Fuji, I'll allow you to
derive this from my post yourself, it is not hard if you know it

even B&W colorants like silver halides have a hue that must be either
maintained or translated in the ICC profile like a three colorant
system, the eye is a three colorant system, I will allow you to derive
B&W yourself, it is not hard if you know it

with the advent of RIMM, ERIMM, and ROMM in ICC you can use digital
manipulation for hybrid systems (you can search for these on the ICC
site and they are from ProPhoto RGB according to wikipedia)

so why would you want to do it the hard way, mechanistically?

1) want to retain analog manipulation methods
2) want to have analog manipulation algorithms within digital
3) want to an analog capture of scene colorimetry
4) multi-stage analog/hybrid systems do not calibrate
(steady-state calibration is a prerequisite for profile characterization)
5) want to design new analog equipment or manipulation
6) want to design new sensitized media for a hybrid system
( a film program was around 5 million at Kodak 17 years ago)
7) want to design a better analog RIMM, ERIMM or ROMM

so how to do it the hard way?

first, you will need a lot of information, the preferred way of getting
this method is from analog media, equipment and software companies, as
opposed to the investment yourself, some analog technology really
requires single layer coatings to resolve crosstalk from spectral
sensitivity and chemical processing, chemical processing can be just the
way it is, process variability across or inside labs, or by design with
things like DIR or DIAR couplers intended to reduce or optimize chemical
crosstalk
http://en.wikipedia.org/wiki/Color_motion_picture_film

Kodak has licensed some hybrid or analog technology to IMAX, the analog
industry may be willing to deal at this point, additionally some analog
and hybrid information may be patented, when I was at Kodak R&D many
things were not patented due to other nations not respecting
intellectual property, PhotoCD was patented as a last ditch effort to
leverage capture film into digital systems

so what type of information will you need?

spectral sensitivity of capture mediums
(for some systems digital capture sensitivity needs resolved to sensor
and filtration)
spectrophotometry of print (subtractive) output mediums
(spectral data might have to be resolved to light source and filtration)
spectroradiometry of display (additive) output mediums
spectroradiometry of analog and hybrid printers
(for some systems such radiometry of equipment needs resolved to light
source and filtration)
chemical colorant response to light of medium (DlogE)
interimage, overall crosstalk of medium
single layer coatings of mediums to resolve chemical versus sensitivity
crosstalk

what are the use cases?
1) captures (digital, hybrid or analog)(scene or like printing density)
2) manipulations (digital, hybrid or analog)
3) outputs (digital, hybrid or analog)

spectral information is a one dimensional look-up table without crosstalk
crosstalks are at least a linear matrix
DlogE is best represented with a rational quadratic, higher math effects
the central linearity, complete linearity effects toe and shoulder,
highlight and shadow detail where dynamic range is low, this is still a
one dimensional look-up table
digital contrast is linear, gamma
hybrid input/output contrast is calibrated for gamma in most cases
multi-stage systems typically use some standard assumptions, mostly what
equipment/software/measurement the systems engineer is working with

any mathematician can take it from here to get all use cases

if you want me to do a use case, just reply, I have a lot of time on my
hands

by the way, there is a book about "making" Kodak film, but not
"designing" it, maybe the author might want to add a understandable
compilation of this to his book
http://www.makingkodakfilm.com/


Many displays will have low dynamic range, narrow color
gamut, low resolution or low frame rates. Maintaining
compatibility with this legacy requires some form of
remapping of the content to the target display gamut.
If this is not sufficiently predictable then the creative
community may decide to stick with the old standards,
because then at least the result is entirely predictable.


if you allowed people their choice of RIMM, ERIMM, ROMM, PRM(G) or some
appearance that is standard to their use case you could solve this

the "looks and feels" of variety of film, filters, etc. could be put
into ICC abstract profiles, like they put such edits into such profiles


Best,
-- J.




--
Dale
  #8  
Old March 1st 14, 01:48 PM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Jeroen[_2_]
external usenet poster
 
Posts: 3
Default dynamic range and exposure latitude?

Hi,

On 2014-03-01 13:17, Dale wrote:
On 03/01/2014 06:08 AM, Jeroen wrote:
You will be happy to learn that the movie and TV industries
are collaborating on new standards for any or all of:
- high dynamic range (luminance between 10^-4 and 10^4 nit)
- wide color gamut (the entire visible spectrum, and more)
- higher static resolution (4k x 2k, 8k x 4k), and
- higher frame rates (60, 120, maybe 240 fps).


mpeg or ICC or ?


SMPTE, MPEG, BDA, ITU, ...

if film workflows exist long enough, I thinkk you could design a hbrid
system with ONE film, ONE chemical process, and a scanner, writer, and
projector best suited to such film


Not likely, the future is digital and digital intermediate.

I think the film could be negative,, higher exposure latitude, but you
would have to have a scanner, writer, projector designed for that film,
this does mean approvals/edits would have to be viewing "soft" display
or display(output) approvals


HDR digital cameras already exist. It's the displays that
are the problem. Or, more often, the lamp power.

a digital projector could receive the right codes values from the right
ICC color management system


Yes yes. Accuracy in Digital Cinema is of prime importance.

http"//www.kodak.com

they claim video clips highlights, there is no "toe" in digital
contrast, and small gamut sRGB doesn't help, I see dress white shirts
clipped on my CRT television


This is all typical of low dynamic range TV.
Trust me that things are about to change in a big way.

with the right film characterization information, one could develop a
hybrid ICC system to suit Kodak's motion picture catalog, if there is
time before digital capture, manipulation and projection replace the
industry's establishment investment


Not likely to happen. Digital is so much more flexible.
But the experience of the Kodak experts is always appreciated.

so what type of information will you need?


Information is one thing, understanding how to use it is
another thing. And then to keep it simple...

any mathematician can take it from here to get all use cases
if you want me to do a use case, just reply, I have a lot of time on my
hands


You are making that clear. ;-)
Today's problem are of a different natu how to best combine
legacy with future needs. To build a standard that can span
decades. And how to reduce the traditional television artefacts
due to trying to do too much with too few bits.

Many displays will have low dynamic range, narrow color
gamut, low resolution or low frame rates. Maintaining
compatibility with this legacy requires some form of
remapping of the content to the target display gamut.
If this is not sufficiently predictable then the creative
community may decide to stick with the old standards,
because then at least the result is entirely predictable.


if you allowed people their choice of RIMM, ERIMM, ROMM, PRM(G) or some
appearance that is standard to their use case you could solve this


Sounds good. Maybe you can give some thought on how a DCI P3
color gamut carried in a BT.2020 wide color gamut can be
automatically mapped back into a BT.709 (sRGB) color gamut ?
There will be a lot of need for that, because most UHD ("4k")
standards will be based on BT.2020 color primaries.

Best,
-- J
  #9  
Old March 2nd 14, 01:24 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

On 03/01/2014 08:48 AM, Jeroen wrote:

Sounds good. Maybe you can give some thought on how a DCI P3
color gamut carried in a BT.2020 wide color gamut can be
automatically mapped back into a BT.709 (sRGB) color gamut ?
There will be a lot of need for that, because most UHD ("4k")
standards will be based on BT.2020 color primaries.


you can do it two ways, mechanistic (hard way), empirical (easy way)

there is a problem of "repurposing" a smaller gamut back into a larger
gamut, best to keep the original with profile information then just
"purpose" it again
--
Dale
  #10  
Old March 2nd 14, 01:37 AM posted to sci.engr.color,sci.image.processing,rec.photo.darkroom,rec.photo.digital,comp.soft-sys.matlab
Dale[_4_]
external usenet poster
 
Posts: 131
Default dynamic range and exposure latitude?

On 03/01/2014 08:48 AM, Jeroen wrote:

Sounds good. Maybe you can give some thought on how a DCI P3
color gamut carried in a BT.2020 wide color gamut can be
automatically mapped back into a BT.709 (sRGB) color gamut ?
There will be a lot of need for that, because most UHD ("4k")
standards will be based on BT.2020 color primaries.


brings up a storage/portability issue, easily solved with ICC

keep a copy of the image in a device independent space with appropriate
RIMM, ERIMM,, ROMM applied like the profile connection space and then
"purpose" it again instead of "repurposing" a file in an ouput device space

you could also keep your edits on the file as ICC abstract profiles
along with the device independent file,, or just keep the edited file in
the working space

mapping gamut can be done the hard way (mechanistic) or the easy way
(empirical)

the easy way is too print a wide variety of machine code values to the
output devices, measure the color or spectral characteristics, and then
choose whether to convert it colorimetrically, absolute colorimetrically
or maintaing saturation (perceptual mapping involves PRM(G) which is a
print space, smaller than display/projection/editing for film or digital

ideally you create a gamut conversions to the profile connection space,
so they are device independent and can be "purposed" instead of "repurposed"

I don't recall the mathematics of gamut mapping, I wasn't that
experienced, but a three dimensional look up table could be used with
linear or high power polynomials

--
Dale
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Digital Dynamic Range and Exposure Latitude Roger N. Clark (change username to rnclark) Digital SLR Cameras 49 August 22nd 09 12:02 AM
Requirements for Good Photography -- Digital Dynamic Range and Exposure Latitude Except for one thing ... Digital Photography 12 August 11th 09 03:03 PM
dynamic range Paul Furman Digital SLR Cameras 36 February 22nd 06 04:05 AM
Are we ignored regarding dynamic range? ThomasH Digital Photography 43 January 1st 05 11:32 PM
Deconfusion request -B&W film exposure latitude Alan Browne Film & Labs 9 November 19th 03 03:48 PM


All times are GMT +1. The time now is 10:33 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright 2004-2017 PhotoBanter.com.
The comments are property of their posters.