Pages: 1 ... 12 13 [14] 15 16 ... 27   Go Down

Author Topic: sRGB vs. Adobe RGB: New color management stand up comic  (Read 124381 times)

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #260 on: August 25, 2014, 03:48:27 pm »

So that's where that underscore comes from! Now why does it appear in Nikon raw file names?
Embedded JPEG preview in the raw?

More interesting stuff:
http://www.digitalpreservation.gov/formats/fdd/fdd000146.shtml
Quote
Exif 2.2, also termed Exif Print, introduced tags to record camera settings, including scene type (portrait, landscape, night scene, etc.), that can be used to guide automatic adjustments before printing in order to best match the photographer's intent. The key difference between Exif 2.21 and Exif 2.2 is support for the Adobe RGB color space without embedding a color profile. In version Exif 2.2, the default color space is sRGB.
« Last Edit: August 25, 2014, 03:51:19 pm by digitaldog »
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Jim Kasson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2370
    • The Last Word
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #261 on: August 25, 2014, 04:00:31 pm »

Embedded JPEG preview in the raw?

Good thinking. That's probably it. Axe to kill fly, though.

Jim

Rhossydd

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 3369
    • http://www.paulholman.com
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #262 on: August 25, 2014, 04:12:24 pm »

In the sRGB print, colors outside of gamut will be clipped, but they won't disappear, leaving white spots on paper.
White spots on paper ? No. Colours that are clipped just end up as saturated as the destination allows, they don't get changed to white in any system I've seen.
Logged

luxborealis

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2798
    • luxBorealis.com - photography by Terry McDonald
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #263 on: August 25, 2014, 04:16:47 pm »

If a photographer, using their new DSLR or Mirrorless camera, takes photos of the eiffel tower and wants to display them on the web, or make 5x7 prints, and that's as far as they are going to venture with their image use, should they use sRGB or AdobeRGB?  

I've read all 13 (and counting) pages of this discussion and have been fascinated. I'm hesitant to jump in as I am not knowledgeable about colour management, however I am a photography instructor and workshop leader and deal with dispelling internet myths on a regular basis.

Gary - Your instructions to your public regarding setting the camera to sRGB will give people more pleasing results right away. Your error is in explaining it with misinformation and not providing them with enough info to make an informed decision. You bashed aRGB as if you have a vendetta against it.

What dismays me most is the way you close the door to the value of using AdobeRGB. It's similar to telling your public: "Just shoot at a low resolution because you'll never use high resolution for the web and album prints anyway". While it may be expedient for the vast number of your followers at that particular point in time, it sets them up for having less than ideal results once they catch on to photography and wish to take it further.

Years ago, I blindly followed similar advice when I lived in Africa and was new to digital photography. Shooting at lower resolution meant I could get more pictures on my memory card. In your case, you suggest shooting in sRGB so that colours will look better right away. But once I knew more about what I was doing and went back to re-visit those images, I was upset that I had followed such narrow-minded, expediency-driven advice. A local chain of camera stores here in southern Ontario still gives the same, unfortunate advice.

Once I started teaching digital photography, I made a vow to myself to never do this to my students. Never assume they don't want to know more, to explore more and to learn more. I take the same 5 minutes and help them to understand better what the advantages and disadvantages are of both. I give them options and let them choose. I don't treat them like robots - they are thinking human beings who appreciate some background.

They have the ability to understand better than you think, especially when you show them a proper XY or XYZ colour space and superimpose one on the other. They can see the advantage of aRGB even if they may not yet be in a position to use it to their advantage. They can then make a properly informed decision. In fact, borrowing just two or three slides from Andrew's presentation (with appropriate credit) would go miles towards everyone having a better understanding of why using aRGB may be a better option if you want to more from your photography than shooting glorified Polaroids.

I like to use the analogy of a tennis court or basketball court. If the cement walls of the gym are built to the exact size of the court, then you are less likely to play as hard and fast, since you would bash up against the cement walls all the time. This is an sRGB colour space, one that is wrongly used for printing when the person operating it is ignorant of colour spaces and profiling. If you shoot in sRGB, you can't play (edit) as hard as you can compared to, for example, an aRGB colour space (or, better yet, ProPhotoRGB) where the cement walls of the gym are beyond the dimensions of the court, thereby giving you room to play the game as it was meant to be played. My students find this analogy to be very helpful in understanding WHY sRGB may be limiting them.

You see, once your audience starts to realize they can do more with their photographs then simply point-shoot & print (or post), once they realize how they can improve their images with just a bit of editing on a computer they already have, they won't thank you for limiting them by evangelizing the sRGB colour space.

Many of us here the LuLa forum are "that type" who want to do more with their photos than shoot and print/post, so we take issue with well-known instructors like yourself, who make broad proclamations backed by misinformation. Stop turning aRGB into the boogeyman man it isn't.

Gary, your print test will do nothing but further entrench the sRGB mindset. Instead, spend your time, effort and money really helping your audience understand the options they have and the trade-offs they may be making. This is the mark of a good instructor
« Last Edit: August 25, 2014, 04:19:02 pm by luxborealis »
Logged
Terry McDonald - luxBorealis.com

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #264 on: August 25, 2014, 04:21:12 pm »

Another reason to capture the test in raw, and another reason why the image content is so critical to the test has to do with how dark saturated colors are affected when printed (again, the output device, gamut, profiles, RI play a role).

One reason we need big RGB working spaces is that they are based on theoretical emissive devices (ProPhoto being very theoretical when you look at what falls outside human vision). RGB working space matrix profiles when plotted 3 dimensionally illustrate that they reach their maximum saturation chroma at high luminance levels which makes sense since they are based on increased saturation Chroma by the addition of more light. The opposite is seen with print (output) color spaces where this is accomplished by adding ink: a subtractive color model. One reason we need such big RGB working space like ProPhoto RGB is due to its simple size and to counter the disconnect between mapping to the output space without potentially clipping colors. There can be issues where very dark colors of intense saturation Chroma (which do occur in nature and we can capture with many devices) don’t map properly with a smaller working space. Many of these darker colors fall outside Adobe RGB (1998). When you encode using a smaller color space, you clip the colors to the degree that smooth gradations become solid blobs in print, again due to the dissimilar shapes and differences in how the two spaces relate to luminance. I suspect this is why Adobe picked ProPhoto RGB primaries for the processing color space in their raw converters.

Here is a link to a TIFF that I built to show the effect of the 'blobs' and lack of definition of dark but saturated colors using sRGB (Red dots) versus the same image in ProPhoto RGB (Green dots). The image was synthetic, a Granger Rainbow which contains a huge number of different possible colors. You can see that the gamut of ProPhoto is larger as expected. But notice the clumping of the colored red vs. green dots in darker tones which are lower down in the plot.



http://www.digitaldog.net/files/sRGBvsPro3DPlot_Granger.tif
There are two plots, one zoomed out to show the entire color space and one zoomed in making it easier to see the clumping of red dots.
Both plots have exactly the same number of colors and thus dots but the gamut is of course different and the grouping of the dots.
The file is about 2.5mb and JPEG just wasn't clear enough to illustrate this so be warned if you have slow bandwidth.

The original RGB working space indicated above WERE converted to an Epson 3880 profile for luster paper. So you ARE seeing the effect of the working space on the output color space.
« Last Edit: August 25, 2014, 04:58:48 pm by digitaldog »
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Jim Kasson

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 2370
    • The Last Word
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #265 on: August 25, 2014, 04:47:01 pm »

RGB working space matrix profiles when plotted 3 dimensionally illustrate that they reach their maximum saturation at high luminance levels which makes sense since they are based on increased saturation by the addition of more light. The opposite is seen with print (output) color spaces where this is accomplished by adding ink: a subtractive color model. One reason we need such big RGB working space like ProPhoto RGB is due to its simple size and to counter the disconnect between mapping to the output space without potentially clipping colors. There can be issues where very dark colors of intense saturation (which do occur in nature and we can capture with many devices) don’t map properly with a smaller working space. Many of these darker colors fall outside Adobe RGB (1998).

Andrew, I know I'm being pedantic and nerdy here, but I think you want to replace the word "saturation" with "chroma" in the above. There is no measure of saturation in CIELab, but CIELuv has one, and surface colors retain their saturation as illuminant brightness is increased provided the relative spectrum is unchanged, as do emissive displays as brightness of the primaries is scaled linearly.

Jim

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #266 on: August 25, 2014, 04:57:40 pm »

Andrew, I know I'm being pedantic and nerdy here, but I think you want to replace the word "saturation" with "chroma" in the above.
I think you're right although I'm wasn't initially sure if Colorfulness would be better or not in this context. Looking through Fairchild now.

Colorfulness: Attribute of a visual sensation according to which the preceved color of an area appears more or less chromatic.
Chroma: Colorfulness of an area judged as proportion of the brightness of similarly illuminated area that appears white or highly transmitting.

Hum.... I think you're right, Chroma it is, thanks!
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

Slobodan Blagojevic

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 18090
  • When everyone thinks the same, nobody thinks
    • My website
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #267 on: August 25, 2014, 05:02:49 pm »

White spots on paper ? No. Colours that are clipped just end up as saturated as the destination allows, they don't get changed to white in any system I've seen.

Jesus, talking about reading comprehension and truncated quoting ... I specifically said:

Quote
... colors outside of gamut will be clipped, but they won't disappear, leaving white spots on paper. They will be replaced by the nearest printable color.

In other words "they won't be leaving white spots."

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #268 on: August 25, 2014, 05:08:34 pm »

In other words "they won't be leaving white spots."
That sure would have been a nasty effect of the rendering intent <g>.
You also said: And the replacement might look even better to some viewers.
I suppose that is indeed possible but I also wonder if it would, depending on the profile and many other factors produce, color shifts. The blue to magenta issue comes to mind. Another reason why the Macbeth is a terrible item to use solely and why some very saturated blues would be necessary.

You think Gary even knows about the different rendering intents and will make a print using RelCol as well as Perceptual?
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".

supercurio

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 58
  • Hi! New here
    • Google+
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #269 on: August 25, 2014, 05:16:04 pm »

Okay so today garyfong is still all like

- I shoot 2 pictures of a color checker with my favorite camera set to sRGB then Adobe RGB
- I show those two images printed to random people
- Out of the blue, they tell me which one they like best.

 :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D :D

What does that even mean?
How do these fellas evaluate anything and.. oh boy.

No, sorry.. staying serious... oh wait  ;D ;D ;D :D :D :D :D :D :P :P :P ;D ;D :D :D
Can't stay serious.

How random people could know what is best from random photos of a color checker target is just beyond me.
But it sure has a comedy effect, thanks again for that :D
Logged

supercurio

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 58
  • Hi! New here
    • Google+
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #270 on: August 25, 2014, 05:53:02 pm »

Of course, if test results are inconclusive, sRGB is declared winner.
Because: reasons.

As garyfong said, Adobe RGB is expected to "blow sRGB away" instead.

We shall all agree right now on the fact that in no case inconclusive results could be caused by the fact this absurd test doesn't make the slightest bit of sense. 
Logged

Rand47

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1882
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #271 on: August 25, 2014, 06:06:00 pm »

I'd like to get back to something Slobodon said early on in this thread, which was roughly that Gary's message re keeping it simple for people working jpeg and on screen that sticking w/ sRGB makes sense.  And so far none of our resident experts have done anything other than affirm this.

Gary's seeming problem is with defending a "simplified" explanation of why this might be so with completely wrong headed grossly oversimplified and "just plain wrong" illustrations.

It would seem that the issue could be settled with an apt quotation:

Einstein: “Everything should be as simple as it can be, but not simpler."

Thank you Albert.  Are you listening Gary?

As for my personal feelings about properlly processed images, working in large color spaces with a color managed workflow, and printed on printers and paper that have wide gamut capatilities.... well my analogy would go something like this.

sRGB = Thomas Kinkade
Wide gamut = Monet

There are lots of folk out there who prefer Kinkade, I suspect.  What does that prove?
« Last Edit: August 25, 2014, 06:13:39 pm by Rand47 »
Logged
Rand Scott Adams

Slobodan Blagojevic

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 18090
  • When everyone thinks the same, nobody thinks
    • My website
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #272 on: August 25, 2014, 06:23:24 pm »

... How random people could know what is best from random photos of a color checker target is just beyond me...

Because their role is not to "know what is best" but to simply say what they prefer or like the most.

It is like expecting voters to "know" which presidential candidate is "best." Some do know, but even they know only what would be best for them or their social group. Most others go for what they like. As much as there are initiatives to let only highly educated voters to vote, that ain't gonna happen. By the same token, what people like or not about their prints is not going to be determined by a bunch of experts.

supercurio

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 58
  • Hi! New here
    • Google+
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #273 on: August 25, 2014, 06:37:50 pm »

Because their role is not to "know what is best" but to simply say what they prefer or like the most.

Please explain how you like the most one or another printed picture representing a colorchecker target.

And what it's supposed to mean.
Logged

hugowolf

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1001
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #274 on: August 25, 2014, 06:47:14 pm »

Please explain how you like the most one or another printed picture representing a colorchecker target.

And what it's supposed to mean.

I was just going to ask the same question. I mean, what's to like about a ColorChecker card?

Brian A
Logged

mouse

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 260
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #275 on: August 25, 2014, 06:53:23 pm »

When my Canon 5D2 is set to AdobeRGB and is doing in-camera Jpegs, the AdobeRGB profile is not embedded into the image.  Only an Exif flag is set.  I wonder how many printing systems and browsers that normally DO read and interpret correctly embedded ICC profiles would actually ignore AdobeRGB if it was flagged only within the EXIF.

Just curious - you know, among us color nerds and measurebaters.

As one still trying to increase my knowledge of color management, may I insert a slightly off topic question here:

The quoted post by Eyeball, and a few others which follow it suggest that there is a distinction between a color profile embedded within the image and a color profile specified simply by an Exif flag.  Can someone clarify this for me.  Where, within the image file, does one find the embedded profile (data) if not within the Exif data?  Does an embedded ICC profile remain intact if the Exif data is stripped from the file?

My understanding (likely flawed) is that Exif data includes ALL metadata in the image file other than the bytes representing the image itself.
« Last Edit: August 25, 2014, 06:59:40 pm by mouse »
Logged

Slobodan Blagojevic

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 18090
  • When everyone thinks the same, nobody thinks
    • My website
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #276 on: August 25, 2014, 06:55:34 pm »

Please explain how you like the most one or another printed picture representing a colorchecker target.  

You are correct. I made a wrong assumption that Gary will be using the color checker as a part of scene containing a range of colors, from natural to man-made objects.

I agree it does not make much sense to like or not a color checker card, if the goal was to compare two color spaces. If the goal was to show that wrongly printed Adobe RGB looks washed out, than I think the general public will prefer the non-washedout version. Which, of course, is a no brainer.

Royce Howland

  • Full Member
  • ***
  • Offline Offline
  • Posts: 155
    • Vivid Aspect Photography
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #277 on: August 25, 2014, 07:05:31 pm »

I'd like to get back to something Slobodon said early on in this thread, which was roughly that Gary's message re keeping it simple for people working jpeg and on screen that sticking w/ sRGB makes sense.  And so far none of our resident experts have done anything other than affirm this.

I don't have nearly the same stature as others here, but I have not affirmed that, not fully anyway. :) As I stated somewhere above, I believe a better piece of advice for some beginners shooting JPEG may very well be to shoot Adobe RGB and work with somebody who knows what they're doing if they need to print or do something else downstream.

That's for the reason luxborealis also just stated above -- shooting JPEG's in sRGB, the narrow range of colour you get in those files is forever. If real-world colour was lost and you later progress to the point where you care more and want to use a print process (for example) that renders fuller colour from the scenes you shot, you can't do it. As everyone who works in a colour managed workflow knows, print labs that are cited as being able to "only print sRGB" in fact can render more colour than sRGB in certain hue ranges (e.g. yellow and blue-green), and have been able to do so for quite some time. Inkjets in turn can render more colour than even Adobe RGB (let alone sRGB) in certain hue ranges, and have been able to do so for some time. (At least Gary Fong, right at the beginning of the video, very briefly acknowledged that people doing pre-press or inkjet printing might have reason to use Adobe RGB, but then he spends the rest of the video essentially trashing that choice so it doesn't look like a good one. I doubt very many folks doing pre-press work are in Gary Fong's target audience, but many inkjet printers might be.)

Slobodan didn't really buy my rationale, and that's fine; I didn't really want to debate with him over it. Because at the end of the day it's not about who of us is right, it's about what is right... for a given photographer. I don't much care what choice anybody makes, as long as it's a good one for them. I do care a lot more if a load of hooey is delivered by an "expert", and misleads people into making bad choices. If a person is okay with limited colour now and forever, by all means shoot JPEG's in sRGB. If a person wants more colour now, advice to shoot sRGB now is not fine. And if a person is okay with less colour now but may want more later from the same files, it's also not fine.

Quote
Gary's seeming problem is with defending a "simplified" explanation of why this might be so with completely wrong headed grossly oversimplified and "just plain wrong" illustrations.

Well, that's not his only problem, in my opinion. His advice has twin problems. First, it's a simplistic recommendation for people without any real regard to where they're at, what they're doing, and how or when they may want to do more than they're doing today. In other words not really qualifying the audience to say "this simplified recommendation applies to you guys, but not to you other guys, and here's why." And second, he's providing bad information based on flawed premises, that leads not just to simplified understanding but in fact wrong understanding that creates bad decision making both now and later.

Those potentially bad decisions made now will continue to affect all images shot based on them, even if a person later decides to up the game with their workflow. Some photographers will be okay with this, saying "oh well, live & learn, I'll just have to shoot some more". Some photographers will be less thrilled that expert advice guided them to make choices that permanently restricted image colour, throwing away something that was there for them on the table if only they had known the true implications of what they were doing. How many people might be in the latter group? Who knows... but why create that group at all, when a barely more involved up-front explanation could eliminate the misleading confusion.

Quote
It would seem that the issue could be settled with an apt quotation:

Einstein: “Everything should be as simple as it can be, but not simpler."

Thank you Albert.

I agree with the reference to Einstein, completely. :) That's the issue with simplistic advice, provided free of context as one-size-fits-all solutions, bolstered by bogus examples. Such advice is almost guaranteed to be simpler than it should be for somebody... and the very people who are seeking out and following such advice are the ones who -- at that moment -- are least able to discern whether it's really the best advice for them or not. Or is even valid at all. It seems to me obligatory for an expert instructor to not only give people folksy, accessible and fun commentary, but in fact to create (at least for the subset of the audience who care) the capability to make informed, good decisions that apply to their own circumstances.

supercurio

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 58
  • Hi! New here
    • Google+
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #278 on: August 25, 2014, 07:12:25 pm »

You are correct. I made a wrong assumption that Gary will be using the color checker as a part of scene containing a range of colors, from natural to man-made objects.

I agree it does not make much sense to like or not a color checker card, if the goal was to compare two color spaces. If the goal was to show that wrongly printed Adobe RGB looks washed out, than I think the general public will prefer the non-washedout version. Which, of course, is a no brainer.

I made a similar assumption initially, thinking Gary would ask people to compare prints with the physical color checker in their hands.

This is where a calibrated camera was required as well.
But apparently it's not what his test is either.

At this point, Gary uses us to make his point "it's a hot debate" and we used him to show: "here's a complete example of how to approach color management wrong, from A to Z"
He might gain mechanically some publicity for his premium channel, and we get entertained while experimenting new ways to explain color science  8)
« Last Edit: August 25, 2014, 07:15:27 pm by supercurio »
Logged

digitaldog

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 20630
  • Andrew Rodney
    • http://www.digitaldog.net/
Re: sRGB vs. Adobe RGB: New color management stand up comic
« Reply #279 on: August 25, 2014, 07:13:24 pm »

You are correct. I made a wrong assumption that Gary will be using the color checker as a part of scene containing a range of colors, from natural to man-made objects.
Nope, despite suggestions otherwise, he's saying that's all he'll use. Might as well just use a gray or white card! Considering that expect for one patch, the target he uses falls within sRGB, do you now see how some are suggesting he's got an agenda and is producing a test with predetermined results to backup his flat earth color management theories? Not that such a video has any bearing on his previous video's in terms of mistakes and misinformation!

Here's exactly what he wrote:
Quote
It'll be images of an X-rite color checker, same lighting, custom white balanced, within seconds of each other.
Why the color checker?  Because it will show the difference between squares.  If I did a portrait, it would be subjective.
Pretty ridiculous I'd hope you would agree.
« Last Edit: August 25, 2014, 07:30:45 pm by digitaldog »
Logged
http://www.digitaldog.net/
Author "Color Management for Photographers".
Pages: 1 ... 12 13 [14] 15 16 ... 27   Go Up