Film Negative Invert and Processing in L* Gamma FAQ

Discussion in 'Digital Darkroom' started by dmitry_shijan, Mar 23, 2021.

  1. digitaldog

    digitaldog Andrew Rodney

    Fine, then we can jot this comment of yours down as rubbish (because due to your misunderstanding of how ACR works, that's exactly what it is):

    Yes, you do seem to find items you don't understand but comment about, a mystery.
    "Learning is not attained by chance. It must be sought for with ardor and attended to with diligence. "-Abigail Adams
    Your lack of diligence is now clear.
    There is nothing empty there. Another of your assumptions.
    I believe you need a primer in understanding Histograms which I don't expect you'll study:
    Video tutorial: Everything you thought you wanted to know about Histograms
    http://digitaldog.net/files/Histogram_Video.mov
    And (look, empty areas and more data to learn):
    Beware the Histogram
     
    Last edited: Apr 23, 2021
  2. Nothing new for me in that basic video about histograms.
    All i wanted to explain here is that different RAW converters produce slightly different "native" scene-referred image look.
    [​IMG]
     
  3. digitaldog

    digitaldog Andrew Rodney

    It WAS explained and in these posts.
    You assume (again) each converter is producing a scene-referred rendering. And they should match. Stop assuming.

    Got Photoshop?
    Make a document and fill it with 50% gray.
    Examine the Histogram. Still confused by the “empty” areas or you are able to understand them even with a video primer on Histograms??? Fill the image with White or Black only. Understand the difference between each and WHY the Histogram shows what it shows?

    Got nothing to do with raw per se. It's got nothing to do with Scene Referred or not per se. But if and when you understand how Histograms are drawn AND accept all raw converters are proprietary and differ based on the SAME raw, differ in what and how they construct that Histogram, maybe you'll connect the dots about “empty” areas of the Histogram.
    Digital imaging 101 really. Nothing new or unexpected for some.....
     
    Last edited: Apr 23, 2021
  4. Assuming, comparing and making conclusions is the core of everything that i do and learn.
    I didn't talk about how different histogram redrawn or previewed in different raw converters
    I exported images from different raw converters with same color space and gamma, put them to PhotoLine and compare their histograms from there.
    I agree that different converters produce a different scene-referred rendering (or whatever you name that "flat" look). And i didn't talk that they should match. I already illustrate and confirm that difference in side by side examples.
    I understand why the Histogram (as well as other more complicated monitoring tools) shows what it shows.
    I can't see nothing bad if i name that "gap" in histogram as "empty space in histogram". But is that terminology really so matter for this particular case? Why cling to words?
     
  5. digitaldog

    digitaldog Andrew Rodney

    Lots of evidence of assuming. Not so much elsewhere. Sorry.
    You have made up terms that don't exist.
    You have complained about an Adobe product you don't understand how to use.
    You have assumed a lot about raw data, Histograms and more; much based on assumptions.
    My paid grade here isn't sufficient to continue trying, sometimes, often in vain, to explain how this stuff actually works with of course, outside references.
    So what? They differ. Nothing at all unexpected from this fact! I don’t know if you are purposely trying not to understand this, or if you are really struggling with it. IF the former, let's move on. If the later, maybe I'll attempt to explain again, all I've already explained about Histograms, resetting curves, how all raw converters differ in rendering (AND HISTOGRAM). My patience with you is limited.
    Again, you seem to have massive issues reading and comprehending. Perhaps it's a difference in native language? I told you this has NOTHING to do per se with scene referred rendering and you either didn't read or understand this as illustrated in the quote above. Clearly your idea of 'flat' being or having anything to do with scene referred shows you didn't read or understand the ICC white paper I co-authored and posted here. I can't help you any further if you refuse to slow dow, read and attempt to comprehend the facts!
    Great, IF so (if) my job is done here (despite your confusion in the last post, quoted here as well).
    Hopefully you found a copy of Photoshop and found out how a Histogram can be reported with flat (what you incorrectly call 'empty') areas. There is absolutely nothing unusual about this or that each raw converter shows this differently.
    You wrote: "i assume that there is always some sort of reserved empty space in debayered source image."
    Your assumption is just incorrect as well as the terminology . It shows an utter lack of understanding of what a Histogram plots. I've tried to explain it, I've provided a video AND article you say you saw/read but the evidence you understand the assumption above is wrong isn't yet clear to me and others I suspect. That's fine, assume and believe the earth is flat if you must.
    You don't despite the fact it isn't a gap or empty space.
    As the Chinese proverb says: "The first step towards genius is calling things by their proper name."
    But if you prefer to make up terms and attempt to confuse yourself and worse, your readers, go for it. It's the opposite of genius.
     
  6. First of all dude, we are not in your "online class" or whatever, so don't act like you are some sort of professor in kindergarten. If you came to participate in my thread please stay calm or go away.
    Don't forget that this thread is all about real life film negative processing workflow, but not about some pure theoretical geek color science tech stuff and terminology.

    A lot of that mess and misunderstanding was started after you introduce that idea of "scene referred rendering" described pdf and article on color.org. I never hear about that scene referred rendering thing before and it is essential that i can do mistakes at the first steps of understanding.
    Anyway, i still have no idea how it may help with film scans processing. There is no clean technical explanation in that article and pdf about what actually those ICC profile do when you convert to them. Only some abstract concepts and the fact that i need to convert image to that profile. (Maybe i need to re-read it few more times).
    I never convert something to something without knowing what is actually going on. So i checked those scene referred ICC profiles with different ICC inspectors and tools and i see now that they do some transformations. I can't explain for myself the purpose of those transformations yet, so i will stay away of those scene referred ICC profiles yet.
    So after these deeper tests now i see that "scene referred rendering" is not the same as uncorrected "flat" export with removed contrast curve in raw editor.

    At least you are correct that i am not a native English speaker. I am from Ukraine but my skills are enough to read/write tech articles in English natively.
    You can see some of my works and contributions to other apps and projects during last years:
    Blackmagic Forum • View topic - Final Explanation of Gamma and Color Shift Problems
    VapourSynth + QTGMC Deinterlace + Hybrid UI FAQ for macOS
    [Legacy] Large List of Suggestions and Requests for Photoline UI and Tools - PhotoLine Forum
    PhotoLine UI Icons Customization Project by shijan on DeviantArt
    Facebook
     
  7. digitaldog

    digitaldog Andrew Rodney

    A lot of the mess was your inability to understand seen referred rendering histograms,color spaces, color accuracy, ACR, AND MORE. We’re done here. What we have is a failure to communicate. More and more likely what we have is a failure for you to be able to read and comprehend, colorimetric facts!

    I agree completely with your last point:
    I have provided plenty of other areas you equally have no idea.

    As to your chops (so called “experience”) if or not as sloppy as your understanding of our discussion, I'm not at all impressed by your multiple misunderstandings locked forever in this post.

    You are lost in color space as the 8 pages of comments have illustrated towards your post here. Happy no one here took you seriously? :(
    Try posting this nonsense in the color management forums on Luminous Landscape and you'll get ever harsher treatment from “your peers” if I can be that generous to you.
     
    Last edited: Apr 24, 2021
  8. And that, Ladies and Gentlemen, is how digitaldog, aka Andrew Rodney, makes himself feel good.
     
  9. Everything i wanted to share for now, i shared here in the first page of this thread.
    Same discussion goes on other forums and people share ideas and suggestions with respect there.
    But here the 7 pages of "discussion" consists of formal spamming by rodeo_joe|1's who seems barely understand difference between color space and gamma, and of digitaldog's nervous insolent posts that seems makes him feel "too smart", but have low practical real life usability and in most cases follow to areas not related to this topic.
     
  10. digitaldog

    digitaldog Andrew Rodney

    Ah, Frans, equally confused by colorimetric facts drops in to troll off topic....again.
    Frans may invent an explanation for “empty spaces” in Histogams which should be a hilarious read.
    Upload any image you have ever “made” to your gallery here yet Frans?
     
    Last edited: Apr 24, 2021
  11. digitaldog

    digitaldog Andrew Rodney

    And immediately dismissed as low practical real life usability.

    Such as?
    Give it a try here; you'll be in for a wake-up call.
    Colour Management
    Frans has suffered the fools arrows he deserves there.

    Neither Joe or I, actually anyone here has taken you seriously due to your assumptions and misunderstood writings. You call that peer review “spamming”. Once again you have shown us; ”Sometimes wrong; never in doubt." -Atul Gawande

    You seem unable to accept that you are not taken seriously by those here who understand the topic. The real troll posted less than an hour ago and has a history of posts worse than your in terms of this topic so feel good about that. At least you have shown us you can take a photograph.
     
  12. Ok "professor" i done few more tests just for fun.
    ICC profiles from https://www.color.org/scene-referred.xalter are cLUT-based ICC profiles.
    linear_RIMM-RGB_v4.icc use ProPhotoRGB color space with Gamma 1.0
    ISO22028-3_RIMM-RGB-exCR.icc use ProPhotoRGB ProPhotoRGB color space with sRGB gamma.

    Based on Histogram look, image converted to these profiles is identical to Image converted to normal custom-made matrix-based ProPhotoRGB color space with Gamma 1.0 and ProPhotoRGB ProPhotoRGB color space with sRGB gamma.

    So thanks to personal independent tests and compare now i have real life proof of my earlier theory. The only point of that "too smart named" scene-referred "workflow" from 2007 was to simply convert image back to ProPhoto color space with Linear or with sRGB gamma. It was done like this because in those times legacy ACR was able to export only to sRGB/sRGB gamma, AdobeRGB/2.2gamma and ProPhotoRGB/1.8gamma profiles.
    In modern ACR you can just export directly to custom-made ProPhotoRGB color space with Gamma 1.0 or any other ICC profile you like

    So what was the point to provide that legacy useless workflow that only confuse things?
     
  13. digitaldog

    digitaldog Andrew Rodney

    What is the average and max deltaE of the images? Based on 8 pages here, I'm not at all willing accept your visual acuity and Histogram analysis due to much of your writing and basic lack of understanding of Histograms.
    Just tell us the colorimetric differences, ideally using dE 2000 formula. You of course have tools to do this right?
    If not, someone here can do that for you but his patience in aiding in your understanding is nearly gone.
    Another assumption or factual? Who other than you provided independent tests that were accepted? Look up "Peer Review" and assume as you must, you're one of our peers.
    Your lack of understanding of ACR and Scene Referred rendering is locked in stone here, no need to continue to post more misunderstandings of ACR.
    That statement again confirms your misunderstandings of ACR as well as your misunderstandings of what Scene Refereed rendering really is.
    Do we need more pages of examples of your already admitted misunderstandings? You've already shown to all your readers here this is CWOBaT (colossal waste of bandwidth and time).
    Like so much text you've ignored, the point was to answer, factually, a process you didn't understand and incorrectly posted:
    Of course, 'Normal Processing" is an assumption and generalization without any fact based explanation so typical of your writings. From someone who's stated he's not using (and has proven utter confusion) over the product. You're not qualified to tell anyone what is possible or impossible in ACR/LR! You can't even figure out how to reset the darn Curves panel!
    What's really impossible is having you read, comprehend and accept colorimetric facts provided here by multiple experts. Something you've as yet never provided. What's really impossible is having you provide a lick of colorimetric proof.
    KISS: Negative Lab Pro
    We done yet or do you need more pages here to illustrate to me, Joe and other readers, you're over your head in this topic?

    "I'm all in favor of keeping dangerous weapons out of the hands of fools. Let's start with typewriters." -Frank Lloyd Wright
    Or in this context, keyboards. :)
     
    Last edited: Apr 24, 2021
  14. Just get it over with already guys.
    Pull 'em out and let's find out whose is the biggest.
    I volunteer to be the judge.

    :rolleyes::rolleyes::rolleyes::rolleyes::rolleyes::rolleyes::rolleyes::rolleyes:
     
  15. digitaldog

    digitaldog Andrew Rodney

    The absurd is the last refuge of a pundit without an argument.
    Of course you can't provide ANY colorimetric data to back up your statements. Just fictional writings. Of course you can't back up any outside peer review of your 'technique' even when asked to do so. Just more imaginary constructs.
    If you have only imagined it, you haven't experienced it.
    You are of course entitled to your uninformed opinions on this subject. As I am entitled to my fact based data points.
    By all means, do get in the last and again, misinformed fact-free post here on this subject. I know you can't help yourself.
     
    Last edited: Apr 24, 2021
  16. So you post again imaginary statements about my skills ("including can't even figure out how to reset the darn Curves panel").
    Now i start really worry, because you forget to quote in the end some random historical person to make appearance of something really important and smart in your post.
     
  17. digitaldog

    digitaldog Andrew Rodney

    Imaginary to you:
    Multiple options exist unknown to you! Nothing complicated once you LEARN how.
    As predicted: By all means, do get in the last and again, misinformed fact-free post here on this subject. I know you can't help yourself. :D:D:D

    One never needs their humor as much a when they argue with a fool."
    -Chinese Proverb
     
    Last edited: Apr 24, 2021
  18. Now i see. You can't mistake because of bold text. Everything written in bold automatically became true.
    More you digg into this strange confrontation - less respect you got from other people.
    I even start to think that the whole concept of your "help" here was simply seed some technical confusion, next show everyone how smart are you and involve confused people to pay for your video master classes where you "explain how to fix everything".
    If you so triggered by that deltaE thing - go compare and measure it yourself. I have no idea why you ask me to do it again and again. It is your thing, not mine. I look at colors and at monitoring tools and it is enough for any real life tests. I don't measure deltaE between images and don't interested to to know if they are different by 0.0001% or by 0.1% in brightness or color somewhere.
     
  19. digitaldog

    digitaldog Andrew Rodney

    Don't and can't: colorimetric data from measurements** would get in the way of your assumptions ("0.0001% or by 0.1% in brightness or color") and misunderstandings of color difference you think you don't see.
    Keep posting; maybe someone like Frans will take you seriously, the rest; not so much.

    ** "I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind."-Lord Kelvin

    Ever heard of him?
     
    Last edited: Apr 24, 2021

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