Ken Rockwell on Color Management

[scott_eaton]

<I>He looks down his nose with condescending derision at everything else (inkjet printers, Windows, Adobe RGB). In other words, if he gets it, it's great; otherwise, it's rubbish. </i><P>For a second there I thought you were talking about Andrew Rodney. I hate to defend Ken, but at least he shoots and produces his own work rather than just provide a service for the people doing the work, ahem.

[digitaldog]

Scotty, good to see you back on the planet. We missed your sense of humor.

 

As for being a legitimate photographer, we've been down this road before. And it has

NOTHING to do with the science fiction Ken's spouting (love the stuff about ink jet

printers).

 

Hang in there Scotty, and keep up the heat. The site isn't as amusing when you're off the planet looking for WMD's in Macintosh's.

[marshall]

I LOVE these threads. I don't need to turn on the t.v. to see conflict and lunacy: I can get it right here on a photography forum!

 

No one's going to listen to me. I don't like to insult poeople; I don't have a controverial website; and I don't have established credibility among photography experts. But with some experience in these matters, I can navigate my way through this and see where some of the real information is. I hope others who stumble on this thread can do so as well.

[pete_su]

Some of the responses here strike me as having the same tone as people who used to

sneer at anyone who didn't do their own printing, as if the transfer of the image from the

negative to paper were where the true soul and artistry of the picture were created.

 

Bullshit.

 

You need to understand color management under very specific circumstances... most of

which are analogous to the needs of those who felt compelled to do their own printing in

the past.

 

Color management is important if

 

- you need to match the color response of different devices.

 

- you need to evaluate images on multiple device and be able to relate what you see on

one to what you see on another with some objective basis

 

- you do your own digital color printing.

 

if these are not true for you, then in general I agree with Ken. Use sRGB and don't think

about it.

 

if these are not true for you, then you have to work harder. but, that does NOT make you

 

(a) smarter

 

(b) a better person

 

It just means that the process that you use to get from digital capture to print is more

complicated.

 

He's probably right about JPEG/RAW too, but I'm addicited to post-capture RAW tweaking.

I don't delude myself into thinking that this particular foible of mine means that I'm taking

better pictures.

[digitaldog]

-->Color management is important if

--> you need to match the color response of different devices.

 

So the display is one device and any print is another right?

 

Of two displays?

[peter_berger]

<p>Yes. And sRGB will match both of those just fine, without your having to particularly

worry about it.</p>

 

<p>Peter Su's point seems to be that for most sophisticated photographers using

standard equipment &mdash those of us who aren't taking pictures of canaries in a field of

goldenrod at sunset and then making prints on our Obscuromat 8500 XT Gamutotron

inkjets — , the only thing you get by <em>actively</em> managing your color

profiles is a more complex workflow and more opportunities to screw up your peterfectly

good photos.</p>

 

I agree.

[digitaldog]

-->Yes. And sRGB will match both of those just fine, without your having to particularly

worry about it.

 

Not the display, not unless you calibrate it to sRGB. That's called color management.

 

There are no output devices other than a CRT display that produce sRGB.

[peter_berger]

Like I said -- you don't need to spend money on overly complicated books about this topic.

<a href="http://www.tleaves.com/weblog/archives/000690.html">Just use sRGB</a>.

[digitaldog]

Like I said, if you want the preview to match anything else but a display in the exact sRGB

behavior, (not a print), you need a profile for the application to properly preview the file to

that device. There's only ONE sRGB output device on the planet. It's a display that has been

calibrated to sRGB specifications (sRGB is a mathematical, synthetically constructed color

space). If you want what you're viewing to match another output device and ALL YOU'RE

USING is sRGB, the only device you can match it to is another sRGB display. And to get two

sRGB displays, you need to calibrate them using hardware and tell the software you want

the output to be sRGB EXACTLY!

 

No output (print) device can produce sRGB. The reference media specified by sRGB is an

emissive display.

 

If you want to pretend otherwise, then you use incorrect and delusional thinking to make

this all simple and pretend that anything can produce sRGB. But that's simply NOT the case

and anyone who believes this doesn't understand what sRGB is nor how it's specified.

[digitaldog]

-->Like I said -- you don't need to spend money on overly complicated books about this

topic. Just use sRGB.

 

BTW, if this link is your article, you better do some serious editing, there's some serious

errors:

 

-->Back in the day, the ICC defined the CIE space for this purpose.

 

You're confusing two very different bodies. The CIE predates the ICC by years. One is an

organization that works on specifications for defining the science and art of lighting.

(Commission Internationale de L??lairage) the other is a group of companies, gathered by

Apple computer to build a cross platform system of defining color management.

 

-->The sRGB color space is defined as a mapping from one triple of values (R,G,B) to a

point in the CIE color space (X,Y,Z). The details are not that important.

 

All color spaces can be defined by CIEXYZ. So you haven't told us anything about the

origins of sRGB or it's specifications. sRGB is not base on "standard" "typical" or any other

type of PC monitor,but is directly derived from the HDTV standard ITU-R BT.709/2. The

specifications are built using math to define a theoretical CRT display and the

specifications are down to the ambient light this theoretical display resides. It's based on a

very old set of phosphors (P22) which are virtually extinct today.

 

-->The actual mapping defines the range of colors that can be represented using sRGB

and things like the default gamma (2.2).

 

Incorrect. There are actually TWO curves used to define sRGB and as such, they are not

gamma curves (they are tone response curves). There's a very important tweak to the sRGB

specifications in the shadows...

 

-->Color profiles are like color spaces,

 

Color profiles DEFINE color spaces! That's all they do. Oh, the use that info to convert from

color space to colors space (using LAB).

 

-->first, for web pictures, it is the only way to know that what the web browser on the

other end of the internet will be looking at something that looks anything like what you

were editing in Photoshop.

 

Wrong again. First, you need a color managed Web Browser to match Photoshop (few

around, none on the PC). Otherwise all the RGB numbers are sent directly to the display

without having a clue about the display profile (which is color management bud) or the

embedded profile (assume sRGB). They don't match. We recommend sRGB simply because

most web browser are NOT color managed and of all the color spaces out there, the one

lowest common reference is sRGB since it's based on 1990's CRT technology and most

people willing can calibrate their displays to something reasonable close to sRGB (which is

color management).

 

-->There is one simple reason for this: Web browsers do not use color management.

 

Incorrect again., Safair does as does IE on the Mac among a few others. You could upload

ProPhoto RGB and the images will appear EXACTLY as they do in Photoshop.

 

-->Suppose you put a lot of pictures up on the web and they are all in JPEG files that are

tagged with the Adobe RGB color space. What will these pictures look like in your

grandmother's web browser? They will look like shit.

 

Except in the browsers many of us are using, they will look just fine.

 

-->For printing, the situation is similar.

 

Not even close! The gamut of my Epson 2400 exceeds that of Adobe RGB (1998). The

gamut potential of my digital camera exceeds that even more.

 

-->Almost all consumer output devices, including those huge digital printing mini-labs

that they have at Costco assume that the incoming file is in the sRGB color space.

 

Assuming a file is in sRGB and having an sRGB gamut are two totally different things.

Those Costco devices do not have an sRGB gamut nor do they output in sRGB. They

assume. You know the old saying about assuming right?

 

-->The truth is that most digital cameras make this choice for you anyway. You shoot,

you get sRGB JPEG files

 

Incorrect again. You're misunderstand the difference between color spaces for encoding

data and color rendering.

 

-->Just like everything in photography, you can get away with being lazy...

 

That about sums up the mindset of the author!

[ellis_vener_photography]

Most of you who are attacking Andrew Rodney now are missing a really important point;

After KR says it is a waste of time he then freely admits he uses color management. Read

his piece. He calibrates and profiles his monitor. On important prints he says he uses

Calypso's profiles. on snapshots he trusts Costco or Wolf's system and he is much more

interested in getting some of your money through kickbacks from dealers than Andrew is

from prfiling people's printers.

 

So sneer at color management if you like, but it absolutely does have its place if you care

about your work.

 

The problem with color management as its implemented today today is that the profiling

devices should be integrated into the printers and as far as I know only HP is doing that

with their new top of the line printers. The process should be invisble to photoraphers

and it just isn't. That I think will come with time.

[ellis_vener_photography]

Most of you who are attacking Andrew Rodney are missing a really important point.

 

After KR says it is a waste of time he then freely admits he uses color management. Read

his piece. He calibrates and profiles his monitor. On important prints he says he uses

Calypso's profiles. On snapshots he trusts Costco or Wolf's system and he is much more

interested in getting some of your money through kickbacks from dealers than Andrew is

from profiling people's printers.

 

So sneer at color management if you like, but it absolutely does have its place if you care

about your work.

 

The problem with color management as it's implemented today is that the profiling

devices should be integrated into the printers --and as far as I know only HP is doing that

with their new top of the line printers. The process should be invisible to photographers

and it just isn't. That I think will come with time.

 

KR is right about one thing though. Today's printers and ink sets and papers as long as

you stick with the manufacturer's inks and papers are much better than they were just two

years ago.

[peter_berger]

"-->There is one simple reason for this: Web browsers do not use color management.

 

Incorrect again., Safair does as does IE on the Mac among a few others"

 

 

Like the man said, while painting in broad strokes: Web browers do not use color

management. Relying on them to do so is anywhere from foolish to downright tragic --

And I say that as someone posting this using Safari. IE for Mac has been a dead and

unsupported product for, let's see, about the last 72 years. If this failure to acknowledge

reality is indicative of the quality of _your_ advice then I feel sorry for your customers.

[digitaldog]

-->Like the man said, while painting in broad strokes: Web browers do not use color

management. Relying on them to do so is anywhere from foolish to downright tragic --

And I say that as someone posting this using Safari.

 

First, I can't fathom why you'd say it's tragic for a web browser to be color managed. You

don't get it bud.

 

2nd, you're WRONG about Safari (or maybe Apple is?):

 

http://www.apple.com/pro/photo/colorsync.html

 

Across-the-Board Accuracy

Because ColorSync ensures that built-in, up-to-date color management specs are

integrated into Tiger, it?s easy for software developers to build color management features

into their applications. So when everything from Mail to Safari to any useful little

shareware program can access the same color management tools, everything on your Mac

works together much more reliably.

 

Unless English is a second language OR you feel Apple doesn't understand how their own

Browser operates (I'd suggest you don't), I think you have a lot of reading to do on the

subject.

[peter_berger]

My point is not "Safari doesn't do color management." Of course it does. My point is that if

you are targeting a photo for the web, then relying on web browsers to do color

management is absolutely utter barking madness, since the _vast majority of them_ don't do

anything useful with color profiles.

[digitaldog]

> My point is not "Safari doesn't do color management." Of course it does. My point is....

 

Oh I could I have misunderstood that? You only wrote:

 

> Web browers do not use color management. Relying on them to do so is anywhere from

>foolish to downright tragic -- And I say that as someone posting this using Safari.

 

So some Web browsers DO color manage? I think we know the answer to that now.

 

> you are targeting a photo for the web, then relying on web browsers to do color

>management is absolutely utter barking madness, since the _vast majority of them don't

> do anything useful with color profiles.

 

Again, how could I have misread what you wrote?:

 

> Relying on them to do so is anywhere from foolish to downright tragic

 

So your solution is to throw up your hands and dismiss color management because only

the good browsers use it. Expecting more to color manage their content is therefore

foolish?

 

Your circular logic is confusing to say the least.

[peter_berger]

Yes. Relying on web browsers to support color management profiles, since most of them

don't, is foolish. I'm glad you now seem to understand.

[peter_berger]

Also, hey, good job quoting me selectively, and removing the part of my sentence that said

"painting in broad strokes..."

[digitaldog]

> "painting in broad strokes..."

 

Oh yes, that makes your loose statements totally on the mark.

 

So you didn't say " Web browers do not use color management" or maybe you meant to

say few web browsers do color management. I must have misunderstood "do not" for

meaning none. I should have understood you wanted to say some don't support color

management. Your writing style is perfectly clear, it must be me.

 

" IE for Mac has been a dead and unsupported product for, let's see, about the last 72

years"

 

That long?

 

-->" Relying on web browsers to support color management profiles, since most of them

don't, is foolish."

 

Relying on cars that use E85 for fuel, since most of them don't, is foolish.

 

Relying on computers that use Mac OS X for as an OS, since most of them don't, is foolish.

 

Relying on wide gamut display for image editing, since most of them don't, is foolish.

 

Relying on you to clearly define what you mean, since most of the time you don't, is

foolish.

 

Relying on web browsers that DO support color management profiles, isn't foolish.

 

We're done here, this is getting far too OT. Back to the topic at hand, Ken's silly article

(and the one you referenced).

[peter_berger]

I want to let people who don't use color-managed web browsers to be able to view my

images. You want to sell books.

 

It's left as an exercise to the reader to figure out which one of us has the bigger axe to grind.

[digitaldog]

A far more useful set of discussions about how sRGB isn't all it's cracked up to be (based

on very old technology), the issues with the web, the FACT that some browsers are color

managed and some interesting tibits about Lightroom can be heard in the first 15 minutes

of the Lightroom Podcast #8:

 

http://photoshopnews.com/2006/07/07/lightroom-podcast-episode-8-posted/

 

That above site will get you to the podcast where you can hear people such as Bruce

Fraser, Thomas Knoll and Mark Hamburg talk about stuff Ken (and a few others) are totally

missing!

[digitaldog]

-->I want to let people who don't use color-managed web browsers to be able to view my

images.

 

They can, they will all just look different from each other unless they apply color

management. It's that simple. Listen to the podcast. It's all very clear!