ISO question

[SmilerGrogan]

And yet, Kiwi is the only person on this forum who knows what he's talking about.

I am sure you are capable of running your own tests to try to prove it. I don't believe you will be able to prove it.

As I've always said, that which can be asserted without proof can be dismissed without proof. Let Kiwi go spin his/her/its wheels elsewhere.

 

[David1961]

And yet, Kiwi is the only person on this forum who knows what he's talking about.

Thank you for your opinion.

We'll just have to agree to disagree

 

[David1961]

You might want to ask your sources where they got this tidbit of inside info because if ISO doesn't do anything to raw files it means the engineers are inept and the executives are criminals because they're making us pay for a function that we're not getting.

There is plenty of info on these forums and the www on what ISO does.

Some of it is fact, some is fiction.

I hope you are able to work out which is which

 

[SmilerGrogan]

And what kind of expert am I, you might ask. I am a journalist which means I am an expert in ascertaining whether someone is qualified to speak on a subject. I've been doing this for more than 30 years and hold an advanced degree in the field so that makes me an expert on experts.

That established, there lots of signs that clearly indicate whether someone is an expert or unmask him as an imposter.

One of the easiest ways to tell an imposter is that they don't respond to direct questions with direct answers. Their favorite trick is to attack the question or the questioner. Here on the DPR forums the most popular dodge used by the frauds is to link to Wikipedia as proof of their claim or make reference to another forum post (sometimes people still make reference to that 2008 article about imaging but less and less). In other words, one of the easiest ways to tell a fraud is that he lacks a working knowledge of the current relevant literature.

Pseudo-experts are also fond of using terminology that is so vague as to be meaningless or applying new and contradictory meanings to existing terms.

But the easiest way to tell a pseudo expert is that they are dead certain of their ideas and never admit that their might be a countervailing explanation.

True experts, by contrast, are never afraid to cite real textbooks and legitimate publications (and despite your hopes, that embarrassing vanity rag that published the "article" on equivalence has been exposed as unworthy of notice).

Experts are also skeptical of their own ideas, they love to be challenged.

Finally, real experts have relevant professional experience, academic credentials, and a vast network of colleagues in the relevant field.

Agreed. What I object to is the self-appointed experts who come in and try to second guess the methods of working photographers based on lack of real-world experience. It's the people who say the photographer should have used a different ISO or a different shutter speed or whatever even though doing so would have produced a different photo from the one the photographer intended.

Care to indicate an example of this? As others have said, it doesn't appear to have happened in this thread.

As for 'self-appointed experts', who here is claiming to be an expert? And, even if you can find someone making that claim, how do you know someone hasn't appointed them? Are you appointing yourself to be a self-appointed expert spotting expert?

 

[David1961]

And what kind of expert am I, you might ask. I am a journalist which means I am an expert in ascertaining whether someone is qualified to speak on a subject. I've been doing this for more than 30 years and hold an advanced degree in the field so that makes me an expert on experts.

Thank you for your opinion.

I am not convinced your oponion is true at all because over the years I have seen too many ocassions where people have pretended to be someone they are not.

 

[Michael Fryd]

You might want to ask your sources where they got this tidbit of inside info because if ISO doesn't do anything to raw files it means the engineers are inept and the executives are criminals because they're making us pay for a function that we're not getting.

If we take the "ISO Is A Lie" claim at face value, they are saying the camera makers are going to a huge amount of time, trouble, and expense to equip every camera with an inoperative function, a sham, a photographic placebo. I think the board of directors would want to know what's going on in their engineering departments.

Here's the other question: If the "ISO is a Lie" people are correct, why aren't camera makers racing each other to save costs by deleting the ISO buttons and menu functions and marketing their cameras as ISO-less? Not having to worry about ISO would make everyone's lives easier as well as represent a giant leap forward in photographic technology.

The benefits are endless, why are the camera makers so tight lipped?

...

On modern digital cameras, the ISO setting serves multiple purposes.

Perhaps the most obvious is that it sets a target exposure for the camera's metering system. Increase the ISO by one stop, and the meter will target an exposure that's one stop lower. If you follow the advice of the meter, then the lower exposure will likely result in a noisier image.

An important function of the ISO setting is that it strongly influences the context for how to interpret the captured data. Does a particular amount of light represent a light area or a dark area? The ISO setting is not the only factor, options like Highlight Tone Priority, or Auto Lightening also come into play. If you put the camera in manual mode, and vary the ISO, you get the same exposure (light on the sensor), but at low ISO settings it may be interpreted as being dark grey, and at high ISO that same exposure may be interpreted as being white.

A third function of the ISO setting is to give the camera a chance to optimize processing for the expected ISO. Remember, ISO sets a target exposure for the metering system. The camera expects to see an exposure in that ball park. A clever camera design might take advantage of knowing what exposure to expect. At a simplistic level, the camera can digitally scale the captured data to a more useful range. The camera can also reconfigure itself for the expected light level. Many cameras can alter their processing such that the camera adds less noise, but has less tolerance for high exposures. This can be a useful configuration for situations where low exposures are expected (i.e. high ISO settings). The result is that some cameras add less noise when set to high ISO.

So "ISO" is not a "lie". However, it doesn't alter "gain" or "sensitivity" in the traditional sense of these words.

Nor does increasing ISO directly increase the image noise. It can easily "indirectly" increase noise. Raising the ISO sets a lower target exposure. If you allow that lower target exposure to happen, then the lower exposure will yield a noisier image.

 

[Chato]

And what kind of expert am I, you might ask. I am a journalist which means I am an expert in ascertaining whether someone is qualified to speak on a subject. I've been doing this for more than 30 years and hold an advanced degree in the field so that makes me an expert on experts.

That established, there lots of signs that clearly indicate whether someone is an expert or unmask him as an imposter.

One of the easiest ways to tell an imposter is that they don't respond to direct questions with direct answers. Their favorite trick is to attack the question or the questioner. Here on the DPR forums the most popular dodge used by the frauds is to link to Wikipedia as proof of their claim or make reference to another forum post (sometimes people still make reference to that 2008 article about imaging but less and less). In other words, one of the easiest ways to tell a fraud is that he lacks a working knowledge of the current relevant literature.

Pseudo-experts are also fond of using terminology that is so vague as to be meaningless or applying new and contradictory meanings to existing terms.

But the easiest way to tell a pseudo expert is that they are dead certain of their ideas and never admit that their might be a countervailing explanation.

True experts, by contrast, are never afraid to cite real textbooks and legitimate publications (and despite your hopes, that embarrassing vanity rag that published the "article" on equivalence has been exposed as unworthy of notice).

Experts are also skeptical of their own ideas, they love to be challenged.

Finally, real experts have relevant professional experience, academic credentials, and a vast network of colleagues in the relevant field.

Bobn2, "expert" or no, completely understands the nature of Digital Cameras. After spending six or seven years arguing with him and people who are actual Scientists about the nature of ISO on Digital, I had to eat crow. You are completely mistaken on the question of ISO, making the logical assumption that since the term derives from film, it must be the same as film.

Sorry to say, it juts ain't so.

By no means do I agree with proponents of auto ISO, although the improvement in digital sensors makes it a viable option for many; for my specific needs, thanks but no thanks, I'm sticking to manual.

 

[petrochemist]

And what kind of expert am I, you might ask. I am a journalist which means I am an expert in ascertaining whether someone is qualified to speak on a subject. I've been doing this for more than 30 years and hold an advanced degree in the field so that makes me an expert on experts.

Thank you for your opinion.

I am not convinced your oponion is true at all because over the years I have seen too many ocassions where people have pretended to be someone they are not.

And FAR too many journalistic reports that are total sensationalist garbage.

The evidence certainly does point towards Journalists having any unusual ability to judge the truth of a source!

 

[kiwi2]

If you are convinced that using Auto ISO cannot possibly improve image quality, I am sure you are capable of running your own tests to try to prove it. I don't believe you will be able to prove it.

I don't deny there can be an improvement. I agree with that point in theory. See one of my posts from the other day...

www.dpreview.com/forums/post/63368580

What I'm getting at is those differences can be quite minor. Here's a couple of JPGs straight off my X-T2. One at ISO 200 1/500 sec and the other at ISO 400 1/1000 sec.


1/500 sec, f/6.4, ISO 200


1/1000 sec, f/6.4, ISO 400

The difference is very minor or next to nothing.

Now look how big a difference there is when you work with the light and change your angle a bit...





This difference is a 100 times more impactful on dynamic range and image quality.

My point is, don't go into full geek mode and believe all the nonsense you read in the dpreview forums. It's not really going to improve your photography that much.

--

1 year with Fuji

Explore this photo album by Pete Oliver on Flickr!

flic.kr

 

[bobn2]

And what kind of expert am I, you might ask. I am a journalist which means I am an expert in ascertaining whether someone is qualified to speak on a subject. I've been doing this for more than 30 years and hold an advanced degree in the field so that makes me an expert on experts.

I've had contact with a lot of very good journalists. I find it strange the your posts don't show any of the signs that we might expect from an expert investigative journalist. I've never once seen you quote a source, I've never once seen you spend any effort actually digging under the discussion to find out what's driving it.

That established, there lots of signs that clearly indicate whether someone is an expert or unmask him as an imposter.

One of the easiest ways to tell an imposter is that they don't respond to direct questions with direct answers. Their favorite trick is to attack the question or the questioner. Here on the DPR forums the most popular dodge used by the frauds is to link to Wikipedia as proof of their claim or make reference to another forum post (sometimes people still make reference to that 2008 article about imaging but less and less). In other words, one of the easiest ways to tell a fraud is that he lacks a working knowledge of the current relevant literature.

A journalist knows that any source might yield useful information and knows how to evaluate the reliability of sources. In the case of Wikipedia, the site is a really useful starting point. The articles are of variable quality, but the quality of an individual article can be easily evaluated since it will cite its sources and there is also a 'Talk' tab which shows you the debates and discussions which have produced the article. Wikipedia also has some very authoritative editors. So, I would think that a real journalist, instead of simply adopting the crass 'if it's Wikipedia it must be useless' pre-judgement, would look at a cited page and evaluate it. What sources does it use? Who has contributed to it? What was the underlying discussion?. What are the credentials of the editor dealing with that page? (Note: Most of the pages concerning photography are under the oversight of **** Lyon - https://en.wikipedia.org/wiki/User:Dicklyon - a very decent photographer in his own right and a scientist of some note, who has made an very large personal contribution to digital photography - I leave you to use your advanced journalism skills to find out a bit about him)

As for 'the current relevant literature', that covers current research topics. None of what we are talking about here is anything like current research, it's old, established science. In any case, research papers would not be a suitable source to cite on 'beginner's questions'.

Pseudo-experts are also fond of using terminology that is so vague as to be meaningless

Which is why a great part of these discussions is about clarifying terminology.

or applying new and contradictory meanings to existing terms.

Which terms are you thinking of? Please do be specific. The terms that get argued about are 'exposure', 'ISO' and 'aperture' - all of these are precisely and well defined in authoritative texts, and no-one on the other side of the argument from yourself is redefining them. That would be you.

But the easiest way to tell a pseudo expert is that they are dead certain of their ideas and never admit that their might be a countervailing explanation.

That would be you also. You haven't identified who you think is a 'self-appointed expert', but most of the people I'd guess are in your frame are completely up for a good debate and willing to test their ideas. They just unreasonably think that the other side of the discussion needs to actually put forward some good arguments before they dismantle the conceptual framework that has developed over a long period of reading, thinking, experience and discussion.

True experts, by contrast, are never afraid to cite real textbooks and legitimate publications (and despite your hopes, that embarrassing vanity rag that published the "article" on equivalence has been exposed as unworthy of notice).

Experts are also skeptical of their own ideas, they love to be challenged.

In my experience, it depends in the quality of the challenge. If the challenge exhibits a similar level of thinking and evidence that goes into one's own side of the argument, it's very welcome, because that's how ideas develop. If it's based on obvious fallacies, failure to think and is obviously at odds with the evidence of the real world, it's not worth wasting one's time over.

Finally, real experts have relevant professional experience, academic credentials, and a vast network of colleagues in the relevant field.

As most of the people on the other side of the debate to you do. Simply because they don't list their degrees, publications, etc. in their signatures here doesn't mean that they don't exist. A real journalist wouldn't assume that simply because something wasn't being advertised it didn't exist, would he?

You put me in mind of a troll on the old 'OT' forum who used to insist he was a 'journalist' over many IDs. He used to claim to be working in Italy, as I remember. It was clear from what he posted that he know about as much about journalism as he did about Italy, which was almost nothing.

Care to indicate an example of this? As others have said, it doesn't appear to have happened in this thread.

And just to point out, strange how the 'journalist' was unable to cite a single factual example of the phenomenon that he was reporting, and instead had to fall back on a polemic containing nothing but his own opinions.

--
...because you know, sometimes words have two meanings.

 

[bobn2]

And yet, Kiwi is the only person on this forum who knows what he's talking about.

So, that excludes you. Therefore, when you say Kiwi knows what he's talking about, you don't know what you're talking about.

 

[David1961]

If you are convinced that using Auto ISO cannot possibly improve image quality, I am sure you are capable of running your own tests to try to prove it. I don't believe you will be able to prove it.

I don't deny there can be an improvement. I agree with that point in theory. See one of my posts from the other day...

www.dpreview.com/forums/post/63368580

What I'm getting at is those differences can be quite minor. Here's a couple of JPGs straight off my X-T2. One at ISO 200 1/500 sec and the other at ISO 400 1/1000 sec.

So we are essentially in agreement.

In my earlier post where I spoke about using common sense I said that in some scenarios differences might be difficult to see, if at all, on a screen.

 

[FingerPainter]

If you are convinced that using Auto ISO cannot possibly improve image quality, I am sure you are capable of running your own tests to try to prove it. I don't believe you will be able to prove it.

I don't deny there can be an improvement. I agree with that point in theory. See one of my posts from the other day...

www.dpreview.com/forums/post/63368580

What I'm getting at is those differences can be quite minor.

Is anybody disagreeing with that?

The difference is very minor or next to nothing.

One person's "good enough" is another's "not as good as it could be". Shouldn't we be happy to let each person draw their own line? Why denigrate those who try to be as good as possible?

Now look how big a difference there is when you work with the light and change your angle a bit...

This difference is a 100 times more impactful on dynamic range and image quality.

IDK how you mange to quantify such a difference, but yes, the difference between front-lit and back-lit can often be more noticeable than the difference of a stop of exposure for a given lightness.

My point is, don't go into full geek mode and believe all the nonsense you read in the dpreview forums. It's not really going to improve your photography that much.

There is a big difference (about 567 times )between talking about the relative importance of different considerations and dismissing those you don't personally care about as "nonsense".

 

[FingerPainter]

You might want to ask your sources where they got this tidbit of inside info because if ISO doesn't do anything to raw files it means the engineers are inept and the executives are criminals because they're making us pay for a function that we're not getting.

If we take the "ISO Is A Lie" claim at face value, they are saying the camera makers are going to a huge amount of time, trouble, and expense to equip every camera with an inoperative function, a sham, a photographic placebo. I think the board of directors would want to know what's going on in their engineering departments.

Here's the other question: If the "ISO is a Lie" people are correct, why aren't camera makers racing each other to save costs by deleting the ISO buttons and menu functions and marketing their cameras as ISO-less? Not having to worry about ISO would make everyone's lives easier as well as represent a giant leap forward in photographic technology.

The benefits are endless, why are the camera makers so tight lipped?

Agreed. What I object to is the self-appointed experts who come in and try to second guess the methods of working photographers based on lack of real-world experience. It's the people who say the photographer should have used a different ISO or a different shutter speed or whatever even though doing so would have produced a different photo from the one the photographer intended.

David1961 wrote:
I set the aperture to get the DOF I want and the shutter speed I need to meet the motion criteria - introduce motion blur or freeze action - and then I let the camera set ISO.

The OP said the photographer was using manual mode which is what I and others have suggested.

If he was also using Auto ISO then he was doing what I and others have also been suggesting.

And I am certainly no expert, self appointed or other wise :-D

Before joining these forums recently I believed the exposure triangle to be correct and that ISO was part of an exposure. Now I know better

David1961 didn't say that ISO is a lie. And he didn't say that the ISO setting has no function.

Going from 'ISO is not a parameter of exposure' to 'ISO is a lie' and 'camera manufacturers are cheating you' is quite a leap. An unjustifiable leap.

 

[FingerPainter]

And what kind of expert am I, you might ask. I am a journalist which means I am an expert in ascertaining whether someone is qualified to speak on a subject.

I've seen plenty of evidence to the contrary. There are all sort of examples of journalists citing unqualified sources. Watch Fox News, though it isn't a problem restricted to a single news outlet.

I've been doing this for more than 30 years and hold an advanced degree in the field so that makes me an expert on experts.

Whether it makes you an expert on experts or an expert on some other aspects of journalism depends on your particular course of study. Holding an advanced degree in journalism doesn't automatically make one an expert on experts.

That established, there lots of signs that clearly indicate whether someone is an expert or unmask him as an imposter.

One of the easiest ways to tell an imposter is that they don't respond to direct questions with direct answers. Their favorite trick is to attack the question or the questioner.

So far so good.

Here on the DPR forums the most popular dodge used by the frauds is to link to Wikipedia as proof of their claim or make reference to another forum post (sometimes people still make reference to that 2008 article about imaging but less and less). In other words, one of the easiest ways to tell a fraud is that he lacks a working knowledge of the current relevant literature.

Pseudo-experts are also fond of using terminology that is so vague as to be meaningless or applying new and contradictory meanings to existing terms.

But the easiest way to tell a pseudo expert is that they are dead certain of their ideas and never admit that their might be a countervailing explanation.

True experts, by contrast, are never afraid to cite real textbooks and legitimate publications (and despite your hopes, that embarrassing vanity rag that published the "article" on equivalence has been exposed as unworthy of notice).

The above set of paragraphs are a great example of the opposite of good journalism. No direct citation of evidence or sources. Vague smears. Reference only by allusion.

If you are a journalist, why not try to write according to the standards of your profession? Who are the pseudo-experts? What specifically have they said that is demonstrably wrong? Where and when did they say it? Why are you qualified to judge that what they say about technical aspects of photography is false?

Experts are also skeptical of their own ideas, they love to be challenged.

Finally, real experts have relevant professional experience, academic credentials, and a vast network of colleagues in the relevant field.

So rather than making vague claims about the sins of nameless individuals, why not make a specific claim about particular individuals. Do bobn2 and Iliah Borg qualify as experts? Why or why not?

 

[bobn2]

You might want to ask your sources where they got this tidbit of inside info because if ISO doesn't do anything to raw files it means the engineers are inept and the executives are criminals because they're making us pay for a function that we're not getting.

If we take the "ISO Is A Lie" claim at face value, they are saying the camera makers are going to a huge amount of time, trouble, and expense to equip every camera with an inoperative function, a sham, a photographic placebo. I think the board of directors would want to know what's going on in their engineering departments.

Here's the other question: If the "ISO is a Lie" people are correct, why aren't camera makers racing each other to save costs by deleting the ISO buttons and menu functions and marketing their cameras as ISO-less? Not having to worry about ISO would make everyone's lives easier as well as represent a giant leap forward in photographic technology.

The benefits are endless, why are the camera makers so tight lipped?

Agreed. What I object to is the self-appointed experts who come in and try to second guess the methods of working photographers based on lack of real-world experience. It's the people who say the photographer should have used a different ISO or a different shutter speed or whatever even though doing so would have produced a different photo from the one the photographer intended.

David1961 wrote:
I set the aperture to get the DOF I want and the shutter speed I need to meet the motion criteria - introduce motion blur or freeze action - and then I let the camera set ISO.

The OP said the photographer was using manual mode which is what I and others have suggested.

If he was also using Auto ISO then he was doing what I and others have also been suggesting.

And I am certainly no expert, self appointed or other wise :-D

Before joining these forums recently I believed the exposure triangle to be correct and that ISO was part of an exposure. Now I know better

David1961 didn't say that ISO is a lie. And he didn't say that the ISO setting has no function.

Going from 'ISO is not a parameter of exposure' to 'ISO is a lie' and 'camera manufacturers are cheating you' is quite a leap. An unjustifiable leap.

For a journalist, Mr Grogan doesn't seem to be very concerned about the truth.

 

[kiwi2]

What I'm getting at is those differences can be quite minor.

Is anybody disagreeing with that?

The difference is very minor or next to nothing.

One person's "good enough" is another's "not as good as it could be". Shouldn't we be happy to let each person draw their own line? Why denigrate those who try to be as good as possible?

Well I did ask the question before how much of a noticeable difference would been seen form the advice you were dishing out...

www.dpreview.com/forums/post/62158559

www.dpreview.com/forums/post/62516542

 

[Michael Fryd]

What I'm getting at is those differences can be quite minor.

Is anybody disagreeing with that?

The difference is very minor or next to nothing.

One person's "good enough" is another's "not as good as it could be". Shouldn't we be happy to let each person draw their own line? Why denigrate those who try to be as good as possible?

Well I did ask the question before how much of a noticeable difference would been seen form the advice you were dishing out...

www.dpreview.com/forums/post/62158559

www.dpreview.com/forums/post/62516542

Modern cameras are capable of very high quality. When you are shooting in favorable conditions, there may be no need to absolutely maximize image quality.

Once, the image quality is "good enough", there may be no visible difference in further improvements.

However, sometimes you may need to shoot in marginal circumstances. It may not be possible to reach the quality level where problems are not visible. In those circumstances, It can make a visible difference to use techniques that maximize image quality

 

[kiwi2]

Modern cameras are capable of very high quality. When you are shooting in favorable conditions, there may be no need to absolutely maximize image quality.

Once, the image quality is "good enough", there may be no visible difference in further improvements.

However, sometimes you may need to shoot in marginal circumstances. It may not be possible to reach the quality level where problems are not visible. In those circumstances, It can make a visible difference to use techniques that maximize image quality

I know. In very low light I need to maximize light gathering potential as much as I can.



Auto-ISO is not on the cards for me here either. Exposures as long as possible before star trailing shows up. As fast an aperture that is still sharp. And stitching frames together for more total light.

Auto-ISO isn't the be-all and end-all on image quality.

--

1 year with Fuji

Explore this photo album by Pete Oliver on Flickr!

flic.kr

 

[FingerPainter]

Modern cameras are capable of very high quality. When you are shooting in favorable conditions, there may be no need to absolutely maximize image quality.

Once, the image quality is "good enough", there may be no visible difference in further improvements.

However, sometimes you may need to shoot in marginal circumstances. It may not be possible to reach the quality level where problems are not visible. In those circumstances, It can make a visible difference to use techniques that maximize image quality

I know. In very low light I need to maximize light gathering potential as much as I can.



Auto-ISO is not on the cards for me here either. Exposures as long as possible before star trailing shows up. As fast an aperture that is still sharp. And stitching frames together for more total light.

Auto-ISO isn't the be-all and end-all on image quality.

I don't think ultra long exposures using a camera with a crippled implementation of Auto-ISO have much to do with OP.

You are right that there are certain circumstances when Auto-ISO is not the best choice.