• June 15, 2023, 7:25 p.m.

    A couple of weeks ago this guide was the subject of some criticism on these forums. Not that it deserved to be picked out, it was just as wrong as most of them are. Still, I left a comment to the publishers pointing out that it was full of errors. Usually when I do that it gets ignored, but this time I got an email from the boss, Rafael, saying that they had asked their staff techie Sandra, who'd agreed that it was erroneous, and they were going to revise it. They asked me to mark up the text for the revision, which I did, and Sandra edited. The result is one of the very, very few web explainers on exposure which isn't full of gross errors. So, kudos to PhotoPills.
    I should say, that neither Sandra nor I wanted to completely eviscerate what the original author had written, so it's not the article that I would have written, and there are some things I don't agree with stylistically, but it doesn't have many errors (I hesitate to say any...).
    So, if you want to point someone at a web guide, why not this:
    www.photopills.com/articles/exposure-photography-guide

  • Members 243 posts
    June 15, 2023, 7:30 p.m.

    And Kudos to you as well.

    Being an editor, I find stuff. Pop Photo recently sent an email covering Nikon all purpose zooms, and they made an error twice on the focal length of a lens. I sent en email and they responded and fixed it with 5 minutes. I was amazed and the lady that handled it was very pleasant and grateful.

  • Members 976 posts
    June 15, 2023, 7:36 p.m.

    Here is a mis-take:
    "Those who know how to correctly expose their photographs regardless of the scene they have in front of them... and those that don't."
    Those who think they know, those who think the camera knows, and those who think.

  • June 15, 2023, 7:49 p.m.

    As I said, it's not how I would have written it. Had I marked up things like that, there wouldn't have been a lot of the original text left.

  • Members 878 posts
    June 15, 2023, 8:51 p.m.

    [deleted]

  • June 15, 2023, 10:14 p.m.

    There's a lor fewer than there were.

    Yes, there is an omission there. More an omission than an error.

    But what it does to the raw file and the JPEG depends on the camera, it is not mandated by ISO. The effect given here is mandated within the standard. If you want to say what the ISO control does on individual cameras, than this artiucle becomes much more complex, and probably fails to serve the purpose of being suitable for beginners. I think the basic principle is 'tell no lies' - not 'put in every truth you can think of'. Again, it's an omission, and a sensible one, not an error.

    Many people seem to call the combination of those things 'the exposure triangle'. In fact that's how it was formed by Peterson. So again, not an error - there is more than one opinion on what is 'the exposure triangle'. Yours just differs from the author's. For myself, I'd have rather excised any reference, but it wasn't my article.

    You sais it. There's loads of rhetoric in this article that I wouldn't have written, but then I'm not the author.

    See the above. I suspect that the author here is talking more about his personal technique rather than hard definitions. It doesn't count as an 'error', it's just not very analytical.

    Again, I think he's talking compositionally here. I don't think the author was very technical. I saw my role, and what I was invited to do, as correcting fundamental errors in the basics, not to expunge everything the author had written, which is what would have happened with your approach.
    I suppose, if it worries you you can volunteer your services.

  • Members 2332 posts
    June 15, 2023, 10:20 p.m.

    Quote :The world is divided into two categories.

    Those who know how to correctly expose their photographs regardless of the scene they have in front of them... and those that don't.

    blog.kasson.com/the-last-word/a-new-way-to-look-at-isolessness-2/

    the world is divided into 3, the third is those that dont care ☺

    "confusion starts when scientists disagree"

  • June 15, 2023, 10:23 p.m.

    The author of this work wasn't a scientist.

  • Members 2332 posts
    June 15, 2023, 10:26 p.m.

    but you corrected the work. so now mash your corrections with Jims latest writings and what do we get !

    conflicting arguments.

  • Members 976 posts
    June 15, 2023, 10:31 p.m.

    There is no disagreement over this trivial matter, nor between scientists, nor between engineers, nor between photographers - given they put a minimal effort to do well-planned experiments.

  • Members 676 posts
    June 16, 2023, 5:01 a.m.

    Fair points to raise. It would be cool if you could contact the author with your criticisms -- I get the feeling that they would appreciate it!

  • June 16, 2023, 7:07 a.m.

    That's not my corrections.

  • June 16, 2023, 7:27 a.m.

    Fundamentally disagree. You're just wrong about this. When you give a description of what something does it's usual that you provide the essential function, not everything that it might do. So, a dictionaray definition of a car says 'a four-wheeled road vehicle that is powered by an engine and is able to carry a small number of people.' It does not say that it will usually provide radio reception to the people in there, that it will often be air conditions, that in many cases it will emit carbon dioxide and pollutants. The ISO definition if what 'ISO' does says it defines the relationship between exposure and lightness. That is what ISO is. All the rest is thangs that an ISO control might do, sometimes does do, but isn't mandated or defined. So, it's not wrong.
    Plus, I think a treatise on all the side effects that occur on different cameras for the ISO control would be very unhelpful. Descriptions of what ISO does are riddled with misleading and often wrong material. If you think otherwise, please suggest an alternative wording.

    No, you don't do that. Language works in two forms. One is colloquial language usage, where things mean what common parlance says they mean. the other is specialist vocabularies where they work by formal definition, usually traced back to the originator of the concept. The second doesn't apply, so far as I can see to the 'exposure triangle'. So it's the former. And in discussions with triangle proponents, it seems that many think of it just as does the author of this article. For myself, I'd rather have expunged all references to the triangle. My markup didn't do that, it just pointed out where discussion of the triangle contained comments that were wrong.

    It's absolutely applicable here. Essentially, DR is about how much information you can capture in the scene. In any case, your comments were again wrong. In imaging, when 'DR' is talked about, it's generally the maximum signal divided by the noise floor, unless it's Bill.

    Than Bill's 'PDR'? Certainly there are. It's very flawed, but as I said, that's a different discussion - and the point here is what is generally understood as 'DR' in the imaging community - For instance here
    The dynamic range of a charge-coupled device (CCD) or complementary metal oxide semiconductor (CMOS) image sensor is typically specified as the maximum achievable signal divided by the camera noise, where the signal strength is determined by the full-well capacity, and noise is the sum of dark and read noises.

    Take it up with the author, not me.

    See above.

  • Foundation 180 posts
    June 16, 2023, 7:39 a.m.

    As ever, Bob, no good turn goes unpunished...

    Tim

  • June 16, 2023, 7:42 a.m.

    Well, the PhotoPills people are grateful, at least 😀

  • Members 2332 posts
    June 16, 2023, 8:56 a.m.

    "Three variables affect exposure: aperture (lens f number), shutter speed and scene luminance."

    wrong.

    Three variables affect "image brightness": aperture (lens f number), shutter speed and scene luminance.

  • Foundation 180 posts
    June 16, 2023, 9:08 a.m.

    I'm going to regret this...! How about:

    Four variables affect "image brightness": aperture (lens f number), shutter speed, scene luminance and ISO.

    An maybe others, as well...