Let's get real..exposure? shutter speed? aperture?

Detail Man wrote:
You must admit, it often becomes little more than a "cheap and dirty" way of attempting to ignore the need to compose frames with selectivity and care. (IMO), "Bookay" seems often the first refuge of the lazy and clueless. I am impressed with the few that have worked out for you, however. In a larger sense, perhaps it does not really (in the end) increase the "keepers" and "gem" rates ?
I understand the use of creamy bokeh in studio and for the occasional abstract background where the subject is a person or object. But for most of the photography I do I always crave more detail. It's lovely that you have the subject nicely in focus, but when I photograph her child I want to be able read the title of the book she's holding in years to come, or see detail in the leaves behind her.

Unfortunately the cliche has become that if you take a portrait, you need sharp eyes and the rest be damned. Then people spend time comparing how creamy the circles are and spend 5 times as much on the lens trhat gives bigger blurrier circles. I honestly don't get it. That's just one kind of shot. And it's nothing like what your eyes see.
 
Sammy Yousef wrote:
Detail Man wrote:
Many beginners don't know much about DoF either.
Well, why else would one adjust F-Number ? I kind of doubt if you would be teaching about "diffraction" to such relative newbies. Adjusting F-Number to attenuate light is just plain stupid.
f/ number is not just a depth of field control. It has other effects.

You don't have to know a great deal about diffraction to know that setting too high an f/ number is going to give you softer pictures.
Wow, Sammy, you've opened my eyes to a whole new world ! So I started a little thread:

http://www.dpreview.com/forums/thread/3475094
f/ number is your primary control of how much light you're letting in when using flash at or below flash sync speed. Shutter doesn't factor in because the flash duration is shorter than the shutter duration. Granted that's not a concept many new photographers understand. (It was a real eye opener when I "got it").
OK. I'll buy that one. In the case of flash, the extra light makes up for the light attenuation.
Most new users don't shoot in Aperture or Manual mode. Should DoF be taught earlier? Yes. But a new photographer is typically overwhelmed with settings and ideas at the start.
Sure. I was. So, get the lowest feasible Shutter Speeds worked out for various situations - and then onward to DOF. It truly is a lot to handle. Have yet to see a thread on these DPR forums where the large bulk of the contributors themselves have not (often) expressed the strangest (non mathematical) linguistic ways of talking and thinking about DOF. Then, in the end (after all the jawing), they likely just make crude guesses, anyway. Many seem to think that their itty-bitty EVF/LCD screens and preview modes will guide them. Good luck with that bit ... ;)
Their first experience with wanting to take control is typically motion blur. At least the beginners I have observed (and my own experience).
Makes sense. Make that Lesson One (Shutter Time). Lesson Two would be DOF (F-Number).
Ideally yes. In practice I've seen few inexperienced camera users in A or M modes.
Well, it would seem that in order to learn about such matters, that is what needs to happen.
Following the above order ensures (nearly) best possible SNR. Minor tweaking of F-Number and/or Shutter Speed can then be used to "fine tune" to the desired recorded Image Brightness.
There are situations in which raising ISO early makes sense. For instance if you walk into a low light concert and refuse to raise your ISO you're going to have trouble. If you're trying to shoot your friends in low light at a party/pub/club, you'd be crazy to refuse to raise ISO.
But that is not what I said. Trying reading what I wrote. I said:

... minimizing as much as is practical (given desired DOF and implementable camera-stability) the F-Number and Shutter Speed prior to adjusting the ISO setting.

A bit of "anticipation" on the ISO setting is fine. The important thing to do is to ensure that the minimum possible ISO setting value is utilized (after adjusting F-Number and Shutter Speed).
...and after a handful of grainy shots users understand this well.
Really ? If so, it's a mystery to me why this whole sensor-level Exposure (as opposed to the mere scaling of ISO settings) has led to scads of agitated and upset people going on and on about how Brightness is essentially no different than sensor-level Exposure (which is pure bunk).

Seems to me that if they (themselves) adjusted F-Number and Shutter Speed prior to ISO as a matter of course in their technique, then they would "get it" (about maximizing SNR by maximizing sensor-level Exposure), and there would not be any issue to froth at the mouth about.
Or is that something that you think is just "too hard" to learn how to do ? If so, time to go "Auto".
Some people get good results never progressing beyond auto.
Then they hardly need much addition help (if any), do they ? Wait till the little box in the preview-screen turns "green", hold your breath, gently squeeze that little button located on top.
There's still framing/composition, timing, people skills etc.
Yeah, but how much of that stuff (of meaningful value) can really be imparted in an instructional setting ? Those things are learned by actually capturing images (as opposed to listening to lectures, advice, and silly "rules of composition"). Everybody is different in what they want to shoot and how they want to shoot it. That road is made by walking (not talking). They need to get out there and do it - then see what results back home on the "big screen".
But yes the technical side is hardly a challenge if they never venture out of auto, and they won't get the most out of their gear. You'd be much better teaching them about the exposure triangle to get their interest and get them utilising other modes before going into intricacies about the definition of Exposure.
Funny thing, though, is that with the squared relationship of the F-Number, nobody calculates that stuff in their head. You just get the basic interplay into your head. The more important part is developing a strategic order of operations in one's setting-adjustment techniques (as I have previously described), so that the DOF and camera/subject stability desired is there, while also maximizing SNR.
Most/all people reading this message are interested in doing better than that. People use a wide variety of different techniques.
Indeed. And the last thing they usually feel that they need is somebody telling them to "change".
I find I grow most when I make a voluntary change/discover a new idea. Like most, I HATE forced change.
Perhaps that's why some of the best people at everything are the ones who teach themselves what they know and figure out. One's own self-criticism - and natural curiosity as to how to improve matters - may well (in some cases, anyway) be a better teacher than some authority-figure, or boring textbook approach ?

I'm a real "do it myself-er" and rarely "read the directions" type person. In the end, I find and reduce the "errors in my ways" my taking an active and direct interest in better understanding what affects what. (I think) in many disciplines, those who want to try to passively absorb knowledge by proxy (especially where aesthetics are involved) may travel a slow road of progress. Jumping in, getting one's hands dirty, and self-criticism is the way that (I, myself) learn.

Education is an admirable thing, but it is well to remember from time to time that nothing that is worth knowing can be taught.
- Oscar Wilde


DM ... :P
 
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Sammy Yousef wrote:
Great Bustard wrote:

You know, and I know, that in the magical world of zero diffraction and noiseless photos regardless of the light, hardly anyone would give a squat about aperture.

If anything, shallow DOF is an annoying crutch for wannabe photographer-artists who don't know any other way to compose a scene. For everyone else, it's all about being able to use a lower ISO so they will have less noisy photos.
Personally, for most photos I HATE shallow depth of field. I want everything sharp in the capture.
Shame that you can't have it, isn't it?
 
bobn2 wrote:
Sammy Yousef wrote:
Great Bustard wrote:

You know, and I know, that in the magical world of zero diffraction and noiseless photos regardless of the light, hardly anyone would give a squat about aperture.

If anything, shallow DOF is an annoying crutch for wannabe photographer-artists who don't know any other way to compose a scene. For everyone else, it's all about being able to use a lower ISO so they will have less noisy photos.
Personally, for most photos I HATE shallow depth of field. I want everything sharp in the capture.
Shame that you can't have it, isn't it?
I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
 
Detail Man wrote:

I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
I think you're mixing up your mechanics. "Gravity" waves are a Newtonian thing.

A detail, to be sure, but an important one.
 
olliess wrote:
Detail Man wrote:

I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
I think you're mixing up your mechanics. "Gravity" waves are a Newtonian thing.

A detail, to be sure, but an important one.
I don't remember that. I'd be grateful for a refresher course. Since Newtonian gravity fields act instantaneously, presumably these waves propagate at infinite velocity. So, what's the relationship between wavelength and frequency?
 
bobn2 wrote:
olliess wrote:
Detail Man wrote:

I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
I think you're mixing up your mechanics. "Gravity" waves are a Newtonian thing.

A detail, to be sure, but an important one.
I don't remember that. I'd be grateful for a refresher course. Since Newtonian gravity fields act instantaneously, presumably these waves propagate at infinite velocity. So, what's the relationship between wavelength and frequency?
"Gravity waves" (waves in fluids with gravity as the restoring force) were studied long before the "theory of gravitation," let alone any notion of "gravitational waves."

They are completely different animals.

As with most waves in a medium, the relationship between wavelength and frequency depends on the details of the medium.
 
olliess wrote:
bobn2 wrote:
olliess wrote:
Detail Man wrote:

I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
I think you're mixing up your mechanics. "Gravity" waves are a Newtonian thing.

A detail, to be sure, but an important one.
I don't remember that. I'd be grateful for a refresher course. Since Newtonian gravity fields act instantaneously, presumably these waves propagate at infinite velocity. So, what's the relationship between wavelength and frequency?
"Gravity waves" (waves in fluids with gravity as the restoring force) were studied long before the "theory of gravitation," let alone any notion of "gravitational waves."

They are completely different animals.

As with most waves in a medium, the relationship between wavelength and frequency depends on the details of the medium.
Thank you for that. It is bookmarked ready for my next 'Pedantry 101' course. I couldn't have done better myself.

--

Bob
 
bobn2 wrote:
olliess wrote:
bobn2 wrote:
olliess wrote:
Detail Man wrote:

I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
I think you're mixing up your mechanics. "Gravity" waves are a Newtonian thing.

A detail, to be sure, but an important one.
I don't remember that. I'd be grateful for a refresher course. Since Newtonian gravity fields act instantaneously, presumably these waves propagate at infinite velocity. So, what's the relationship between wavelength and frequency?
"Gravity waves" (waves in fluids with gravity as the restoring force) were studied long before the "theory of gravitation," let alone any notion of "gravitational waves."

They are completely different animals.

As with most waves in a medium, the relationship between wavelength and frequency depends on the details of the medium.
Thank you for that. It is bookmarked ready for my next 'Pedantry 101' course. I couldn't have done better myself.
Well, it would certainly be hard to be more disingenuous than you just were. But definitely, for pedantry, it could rank up there with your best efforts.
 
bosjohn wrote:
bobn2 wrote:
bosjohn wrote:
gollywop wrote:
bosjohn wrote:
Great Bustard wrote:
tomhongkong wrote:

It's fun to read all those posts on exposure and what it means, but let's get back in the land of reality.
Is this land to be found on DPR? ;-)
Photography has a number of terms which are not literal, but which have come to mean something specific through long use. It is pretty senseless to try to change something which is clearly understood (or should be) by the majority of photographers.
And photography has a number of terms with precise, and conceptually simple, definitions that are misused.
Exposure was originally (I think) just a measure of how long you took the lens cap off your plate camera and literally 'exposed' the emulsion to light. Without a measure of the size of the lens this is a pretty meaningless term so 'exposure' became a composite measure of time and lens 'aperture' and measures the amount of light falling on the emulsion/sensor or whatever. Amount of light ...nothing to do with film speed, sensor equivalent iso, or how the image turns out.
Actually, the exposure is the density of the light falling on the sensor (recording medium), not the total amount of light (Total Light = Exposure x Effective Sensor Area).
(It actually refers to amount of light per unit of sensor area, as well, thereby removing the misunderstanding that there is more light 'gathered' by an FF camera than an MFT...More total light, maybe, but not in terms of per sensor area)
I see you beat me to it!
Aperture is another composite term, properly understood but misused. Aperture implies a linear dimension, but we have used the term for a dimensionless ratio (F number). In reality, the 'aperture', the size of the object lens, does not tell us much without knowing the FL, and converting it to an F number...but we all know what we mean by 'aperture' which becomes an extremely useful measure.
You mean something like this?

The term "aperture", by itself, is vague -- we need a qualifying adjective to be clear. There are three different terms using "aperture":
  1. The physical aperture (iris) is the smallest opening within a lens.
  2. The virtual aperture (entrance pupil) is the image of the physical aperture when looking through the FE (front element).
  3. The relative aperture (f-ratio) is the quotient of the focal length and the virtual aperture.
Thus, the "f" in an f-ratio stands for focal length. For example f/2 on a 50mm lens means the diameter of the virtual aperture (entrance pupil) is 50mm / 2 = 25mm. Likewise, a 50mm lens with a 25mm virtual aperture has an f-ratio of 50mm / 25mm = 2.
Shutter speed is another. What has the speed of the shutter got to do with anything unless we know how far it travels, and possibly how the closing blade(s) also perform? What we mean is shutter open time, but we all know what we mean by 'shutter speed'
Sure.
I am sure you can think of other similar terms
Like ISO? ;-)
Our use of the term, 'Exposure' looks very precise, as long as we keep away from iso (in camera processing), what next? does 'exposure' include adjustment in LR as well..why distinguish between in camera processing and post processing?
Exposure is what exposure is defined as; ISO is what ISO is defined as. There's a reason that ISO is not an element of exposure and there's a reason that exposure and ISO are both elements of the brightness of the photo.

Whether or not any particular person cares, or whether or not this will help any particular person produce a more "successful" photo, however, is another matter all together.
These two posts have done an admirable job of explaining what a scientific meaning could be for exposure in relation to photography however The English language is not any way near a simple as that.

Words get meanings in any of a number of ways one of the most potent is usage. For the vast majority of photographers exposure means manipulation of the aperture (common usage again say these are the little numbers on the lens barrel ) and shutter speed ( again in common usage the settings on the camera that regulate the shutter) in a direct relation to the iso being used.

iso is an acronym for International Standards Organization and replaced an older asa system of rating film sensitivity called asa, The reason for iso is to standardize what different film makers around the world mean when they rate their emulsions. However history of film photography teaches us that like now iso is an elastic and movable concept and changing the iso of a film up or down with corresponding changes in processing will produce predictable changes in the resulting negatives such as increasing or decreasing grain contrast and sharpness. So in lieu of this ISO then becomes part of exposure equation under common usage of English.
Your conclusion is a non-sequitor. The argument is specious.
I believe you will find common usage a very powerful means of defining words.
Could you please explain how common usage defines words? Could you please further explain how one should extract the meaning from 'common usage'?

--
Bob
in the sixties up tight meant to be good with something then later changed though usage to mean a bad thing being scared or stressed at something, the word bemused originally meant confused now is used interchangeably with amuse and so on there are many many examples;
bemused still means confused. It is still only erroneously used "interchangeably with amuse" by the ignorant. But you're correct: language is a very flexible thing, particularly the English language. But, if you're an educated person attempting to communicate intelligently and intelligibly with other educated people, you will have learned the proper meanings for words and you would use them correctly.

Of course, that's a big IF. :-)

--
gollywop



D8A95C7DB3724EC094214B212FB1F2AF.jpg
 
olliess wrote:
bobn2 wrote:
olliess wrote:
bobn2 wrote:
olliess wrote:
Detail Man wrote:

I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
I think you're mixing up your mechanics. "Gravity" waves are a Newtonian thing.

A detail, to be sure, but an important one.
I don't remember that. I'd be grateful for a refresher course. Since Newtonian gravity fields act instantaneously, presumably these waves propagate at infinite velocity. So, what's the relationship between wavelength and frequency?
"Gravity waves" (waves in fluids with gravity as the restoring force) were studied long before the "theory of gravitation," let alone any notion of "gravitational waves."

They are completely different animals.

As with most waves in a medium, the relationship between wavelength and frequency depends on the details of the medium.
Thank you for that. It is bookmarked ready for my next 'Pedantry 101' course. I couldn't have done better myself.
Well, it would certainly be hard to be more disingenuous than you just were.
I'm confident you could do it without breaking a sweat.
 
Sammy Yousef wrote:
gollywop wrote:
At no point did I say that a photographer should set their ISO inappropriately. So you're arguing a straw man there.
Congratulations, you've graduated from speciousness to sophistry.
No, I disagree. But you're stuck on semantics. ;-)
Well, perhaps so, Sammy. And just to prove it, I'll note that that should be stuck in semantics.

But there is nothing wrong with semantics. It's hard to have an intelligent discussion if people don't care about the meanings of the words they use and the logical constructs and implications of what they say. That's what semantics is all about. One doesn't get stuck in it, one employs it.



--
gollywop



D8A95C7DB3724EC094214B212FB1F2AF.jpg
 
bobn2 wrote:
olliess wrote:
bobn2 wrote:
olliess wrote:
bobn2 wrote:
olliess wrote:
Detail Man wrote:

I would think that such things would be trivial for a relativistic mechanic. Use "gravity-waves". :P
I think you're mixing up your mechanics. "Gravity" waves are a Newtonian thing.

A detail, to be sure, but an important one.
I don't remember that. I'd be grateful for a refresher course. Since Newtonian gravity fields act instantaneously, presumably these waves propagate at infinite velocity. So, what's the relationship between wavelength and frequency?
"Gravity waves" (waves in fluids with gravity as the restoring force) were studied long before the "theory of gravitation," let alone any notion of "gravitational waves."

They are completely different animals.

As with most waves in a medium, the relationship between wavelength and frequency depends on the details of the medium.
Thank you for that. It is bookmarked ready for my next 'Pedantry 101' course. I couldn't have done better myself.
Well, it would certainly be hard to be more disingenuous than you just were.
I'm confident you could do it without breaking a sweat.
You were clearly confused and had asked for a "refresher." I gave a straightforward answer. So yes, it was pretty disingenuous to then turn around and call it pedantic.
 
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Sammy Yousef wrote:
Great Bustard wrote:

I'll give you that using flash well requires a certain level of technical knowledge, which, incidentally, I lack (I don't use flash).
I recommend learning. It's a real eye opener, and being able to control the light is a boon to creativity.
Some day.
However, aside from flash, then, Auto Mode (A) or Program Mode (P), Auto ISO, and OOC jpgs -- honestly, does a beginner need to know anything more? Maybe switch to Time Priority Mode (Tv) if they're getting too much motion blur much of the time, and EC if their photos are consistently too bright or too dark.
My own bit of pedantry - Mode A usually refers to Aperture Priority, not Auto mode, but that's a very minor point.
I'll take the hit on that -- apologies.
Seriously -- look at the challenge winners here on DPR and ask yourself, honestly, if any of those shots had been taken in the manner detailed above then they'd not have won.
If DPR challenge winners can't do better than a novice starting out, we have a real problem.
I would disagree with that. I wouldn't be surprised if some novice took way better pics than I did with a cell phone.
Nevertheless it is possible to take a picture in Program or Shutter priority that is first rate. It's just easier and more likely if you take a bit more control.
If so, I expect it's only true for specific photography (e.g. macro with focus stacking or astrophotography) and very rarely true for the types of pics you see in the challenges.

I bet not all DPR challenge winners would agree with you that ISO is not part of exposure though.
I'd be surprised if more than 1% agreed with me on that point, or if more than 1% cared. However, it would all come from them thinking that exposure is the same thing as brightness, and that noise is due entirely to the sensor and the ISO setting.
 
gollywop wrote:
Sammy Yousef wrote:
gollywop wrote:
At no point did I say that a photographer should set their ISO inappropriately. So you're arguing a straw man there.
Congratulations, you've graduated from speciousness to sophistry.
No, I disagree. But you're stuck on semantics. ;-)
Well, perhaps so, Sammy. And just to prove it, I'll note that that should be stuck in semantics.
:-D

But there is nothing wrong with semantics. It's hard to have an intelligent discussion if people don't care about the meanings of the words they use and the logical constructs and implications of what they say. That's what semantics is all about. One doesn't get stuck in it, one employs it.
I agree. We have two camps:
  • Camp A: exposure is the same thing as brightness and noise comes entirely from the sensor and the ISO setting.
  • Camp B: exposure is the density of the light falling on the sensor, the ISO setting is about the [pre-] processing of that light, and noise comes from the total amount of light falling on the sensor along with the sensor efficiency.
As we can all see, Camp B is unnecessarily complicates things. ;-)
 
Great Bustard wrote:
gollywop wrote:
Sammy Yousef wrote:
gollywop wrote:
At no point did I say that a photographer should set their ISO inappropriately. So you're arguing a straw man there.
Congratulations, you've graduated from speciousness to sophistry.
No, I disagree. But you're stuck on semantics. ;-)
Well, perhaps so, Sammy. And just to prove it, I'll note that that should be stuck in semantics.
:-D
But there is nothing wrong with semantics. It's hard to have an intelligent discussion if people don't care about the meanings of the words they use and the logical constructs and implications of what they say. That's what semantics is all about. One doesn't get stuck in it, one employs it.
I agree. We have two camps:
  • Camp A: exposure is the same thing as brightness and noise comes entirely from the sensor and the ISO setting.
  • Camp B: exposure is the density of the light falling on the sensor, the ISO setting is about the [pre-] processing of that light, and noise comes from the total amount of light falling on the sensor along with the sensor efficiency.
As we can all see, Camp B is unnecessarily complicates things. ;-)

Come on now, don't exclude Camp C:

Believes exposure is the result of the quantity of light that interacts with the film/sensor based on how long the film/sensor is "exposed" to the light and the effect that the optics have on the lights intensity.

Believes ISO is the sensitivity of the film/sensor that gets increased to artificially boost the exposure when the required light intensity for a proper exposure is unavailable.

Grain/noise is a byproduct of higher ISO.

Also refuses to join a camp that believes light can be dense since it cannot.
 
Sammy Yousef wrote:
Great Bustard wrote:

You know, and I know, that in the magical world of zero diffraction and noiseless photos regardless of the light, hardly anyone would give a squat about aperture.

If anything, shallow DOF is an annoying crutch for wannabe photographer-artists who don't know any other way to compose a scene. For everyone else, it's all about being able to use a lower ISO so they will have less noisy photos.
Personally, for most photos I HATE shallow depth of field. I want everything sharp in the capture. I embrace the background as part of the photo and the scene, and don't to sooth myself with bokeh blobs.

I'll use wider apertures it if light is limited because otherwise high ISO will turn everything to mush and I still lose sharpness. But in a perfect world sensors would improve to the point where if you could see it you could photograph it sharply in high detail. Laws of physics might get in the way of that dream (more than) a little for DSLR sized cameras...

I own 2 f/1.8 primes and an f/2.8 macro. The rest of my glass is consumer stuff starting at f/3.5 or f/4.5. I'm content with that.
Just so we have a context:

Canon 5D + 50 / 1.2L @ f/1.2, 1/160, ISO 100

Canon 5D + 50 / 1.2L @ f/1.2, 1/160, ISO 100

Canon 5D + 50 / 1.2L @ f/1.2, 1/60, ISO 100

Canon 5D + 50 / 1.2L @ f/1.2, 1/60, ISO 100

Canon 5D + 50 / 1.2L @ f / 1.2, 1/160, ISO 100

Canon 5D + 50 / 1.2L @ f / 1.2, 1/160, ISO 100

Canon 5D + 50 / 1.2L @ f / 1.2, 1/250, ISO 100

Canon 5D + 50 / 1.2L @ f / 1.2, 1/250, ISO 100

Canon 5D + 50 / 1.4 @ f / 1.4, 1/6400, ISO 50

Canon 5D + 50 / 1.4 @ f / 1.4, 1/6400, ISO 50

Canon 5D + 24 / 1.4L @ f / 1.4, 1/320, ISO 100

Canon 5D + 24 / 1.4L @ f / 1.4, 1/320, ISO 100

Canon 5D + 100 / 2 @ f / 2, 1/250, ISO 100

Canon 5D + 100 / 2 @ f / 2, 1/250, ISO 100

Canon 5D + Sigma 70 / 2.8 macro @ f/2.8, 1/500, ISO 100

Canon 5D + Sigma 70 / 2.8 macro @ f/2.8, 1/500, ISO 100

Canon 5D + 200 / 2.8L @ f/2.8, 1/1600, ISO 100

Canon 5D + 200 / 2.8L @ f/2.8, 1/1600, ISO 100

Canon 5D + 24 / 1.4L + CPL @ f/1.4, 1/2500, ISO 100

Canon 5D + 24 / 1.4L + CPL @ f/1.4, 1/2500, ISO 100

I always think context is important.
 
69chevy wrote:
Great Bustard wrote:
gollywop wrote:
Sammy Yousef wrote:
gollywop wrote:
At no point did I say that a photographer should set their ISO inappropriately. So you're arguing a straw man there.
Congratulations, you've graduated from speciousness to sophistry.
No, I disagree. But you're stuck on semantics. ;-)
Well, perhaps so, Sammy. And just to prove it, I'll note that that should be stuck in semantics.
:-D
But there is nothing wrong with semantics. It's hard to have an intelligent discussion if people don't care about the meanings of the words they use and the logical constructs and implications of what they say. That's what semantics is all about. One doesn't get stuck in it, one employs it.
I agree. We have two camps:
  • Camp A: exposure is the same thing as brightness and noise comes entirely from the sensor and the ISO setting.
  • Camp B: exposure is the density of the light falling on the sensor, the ISO setting is about the [pre-] processing of that light, and noise comes from the total amount of light falling on the sensor along with the sensor efficiency.
As we can all see, Camp B is unnecessarily complicates things. ;-)
Come on now, don't exclude Camp C:
I''m not sure if you count yourself as being in Camp C, but I guess you do. In which case you are incorrect or incomplete on all counts.
Believes exposure is the result of the quantity of light that interacts with the film/sensor based on how long the film/sensor is "exposed" to the light
Good start, except the quantity of light a.k.a. luminous energy, already includes the time dimension, so you have included time twice. You have also "defined" exposure using the word exposed, which gains no logical legitimacy by putting it in quotes. This, in itself, renders your definition meaningless. You also do not stipulate whether you are referring to the light per unit area (i.e., its density) or the light over the entire sensor. If the former, you'd be on the right track; if the latter you would not be.
and the effect that the optics have on the lights intensity.
Since your notion of exposure stipulates the light's interaction with the sensor, it has already passed through the optics, so this is an nappropriate appendage to your statement and merely reflects confusion on your part.
Believes ISO is the sensitivity of the film/sensor that gets increased to artificially boost the exposure when the required light intensity for a proper exposure is unavailable.
In-camera ISO has no effect on the sensitivity of the sensor. Your lack of understanding is showing badly here. There's some hope, however, since there is some tangential indication here that you are recognizing that ISO is separate from exposure. But the hope is somewhat dimmed by the fact that it is by no means clear what you mean by a "proper exposure" -- so this element of your Class C is ambiguous.
Grain/noise is a byproduct of higher ISO.
Grain and noise are two separate things. Shot noise is determined entirely by the total light (exposure properly defined times sensor area), and is independent of in-camera ISO.
Also refuses to join a camp that believes light can be dense since it cannot.
And, as a result, you were unable to even give an indication in your above definition of "exposure" whether you were talking about the per-area light (density) or total light, a critical aspect of a proper definition of exposure. It is not even clear if you are aware that the distinction is necessary.

--

gollywop

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gollywop wrote:
69chevy wrote:
Great Bustard wrote:
gollywop wrote:
Sammy Yousef wrote:
gollywop wrote:
At no point did I say that a photographer should set their ISO inappropriately. So you're arguing a straw man there.
Congratulations, you've graduated from speciousness to sophistry.
No, I disagree. But you're stuck on semantics. ;-)
Well, perhaps so, Sammy. And just to prove it, I'll note that that should be stuck in semantics.
:-D
But there is nothing wrong with semantics. It's hard to have an intelligent discussion if people don't care about the meanings of the words they use and the logical constructs and implications of what they say. That's what semantics is all about. One doesn't get stuck in it, one employs it.
I agree. We have two camps:
  • Camp A: exposure is the same thing as brightness and noise comes entirely from the sensor and the ISO setting.
  • Camp B: exposure is the density of the light falling on the sensor, the ISO setting is about the [pre-] processing of that light, and noise comes from the total amount of light falling on the sensor along with the sensor efficiency.
As we can all see, Camp B is unnecessarily complicates things. ;-)
Come on now, don't exclude Camp C:
I''m not sure if you count yourself as being in Camp C, but I guess you do. In which case you are incorrect or incomplete on all counts.
Believes exposure is the result of the quantity of light that interacts with the film/sensor based on how long the film/sensor is "exposed" to the light
Good start, except the quantity of light a.k.a. luminous energy, already includes the time dimension, so you have included time twice. You have also "defined" exposure using the word exposed, which gains no logical legitimacy by putting it in quotes. This, in itself, renders your definition meaningless. You also do not stipulate whether you are referring to the light per unit area (i.e., its density) or the light over the entire sensor. If the former, you'd be on the right track; if the latter you would not be.
Please stay off of Wikipedia. Your credibility will thank you for it. An unverified article that says "sometimes refered to" doesn't cut it. By quantity of light, I made no reference to luminous energy. I mean quantity of light. I need not refer to unit of area since I said interacting with film/sensor.

Please also note that what I believe exposure to be is not me "defining" it.
and the effect that the optics have on the lights intensity.
Since your notion of exposure stipulates the light's interaction with the sensor, it has already passed through the optics, so this is an nappropriate appendage to your statement and merely reflects confusion on your part.
You assume I meant the lens is always on the camera. You assumed wrong like usual.
Believes ISO is the sensitivity of the film/sensor that gets increased to artificially boost the exposure when the required light intensity for a proper exposure is unavailable.
In-camera ISO has no effect on the sensitivity of the sensor. Your lack of understanding is showing badly here. There's some hope, however, since there is some tangential indication here that you are recognizing that ISO is separate from exposure. But the hope is somewhat dimmed by the fact that it is by no means clear what you mean by a "proper exposure" -- so this element of your Class C is ambiguous.
If you can find a random definition on a site where you can pay to add your own, why are you now clueless as to what proper exposure means?

Maybe you can also google sensitivity while you are at it. I can twist it to apply to the sensor. I have been paying attention....
Grain/noise is a byproduct of higher ISO.
Grain and noise are two separate things. Shot noise is determined entirely by the total light (exposure properly defined times sensor area), and is independent of in-camera ISO.
Also refuses to join a camp that believes light can be dense since it cannot.
And, as a result, you were unable to even give an indication in your above definition of "exposure" whether you were talking about the per-area light (density) or total light, a critical aspect of a proper definition of exposure. It is not even clear if you are aware that the distinction is necessary.
Again, I didn't try to define anything, so your assumption is again wrong. I stated what I believed. Since you can't prove otherwise, my theroy is as valid as yours..
--

gollywop

D8A95C7DB3724EC094214B212FB1F2AF.jpg
I figured you would be quick to take the bait.

It's like fishing with dynamite.

My guess at your response.

Fishing is done either with a rod and reel or a net: therefore it is not possible to be done with dynamite...

You can fish with a spear, but it is called spearfishing.

These findings that I googled should prove to you that you are wrong and I am right.


Regardless of your noble attempts to school me, you and the Great Tard still fail to grasp that light has no density.

If you must insist that it does, could you please provide me with the standard unit of measurement? I am teaching a class on quantum mechanics soon, and would like to add it to my material.
 

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