# Exposure



## jcdeboever (Mar 9, 2016)

What are some scenarios that would warrant a decision to under expose or over expose in camera using digital or film? Hopefully this is not too generic of a question. 

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## pixmedic (Mar 9, 2016)

when you want to do more work in post.


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## jcdeboever (Mar 9, 2016)

pixmedic said:


> when you want to do more work in post.


I never want that. Maybe I am not clear. There are buttons or dials on my camera, I assume they are there for a purpose. Also, Hedgecoe book mentions it (film) but does not go into detail about it. My manuals are not helpful. 

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## Ysarex (Mar 9, 2016)

Underexpose: a) Failure to bring a tripod. b) Moving subject.
Overexpose: Never.

You're about to get into a convoluted discussion about what is correct exposure. What do you mean by underexpose and overexpose and relative to what definition of correct exposure?

Joe


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## astroNikon (Mar 9, 2016)

have you looked into  High-Key and Low-Key photography ?
Using lighting style to create mood: High-key and low-key lighting :: Digital Photo Secrets


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## jcdeboever (Mar 9, 2016)

Ysarex said:


> Underexpose: a) Failure to bring a tripod. b) Moving subject.
> Overexpose: Never.
> 
> You're about to get into a convoluted discussion about what is correct exposure. What do you mean by underexpose and overexpose and relative to what definition of correct exposure?
> ...


Just curious as to why it is available and why would I need this feature. 

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## Ysarex (Mar 9, 2016)

jcdeboever said:


> pixmedic said:
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Cameras have an EC (exposure compensation) button or dial that permits you to set a correct exposure in circumstances where the camera's internal metering system would under or over expose.

Joe


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## pixmedic (Mar 9, 2016)

jcdeboever said:


> pixmedic said:
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which buttons/dials are you talking about?
theres a few of those on my camera. maybe more on yours.


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## Ysarex (Mar 9, 2016)

astroNikon said:


> have you looked into  High-Key and Low-Key photography ?
> Using lighting style to create mood: High-key and low-key lighting :: Digital Photo Secrets



That's lighting not exposure. You still set a correct exposure in high and low key lighting.

Joe


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## pixmedic (Mar 9, 2016)

Ysarex said:


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oooooh yea...
its probably that. 

it has to do with the way the camera meters, what metering mode you are using, and if spot metering what area you are metering for -vs- the exposure of the remaining area. 
there are plenty on the forum far better suited to explaining it than I am. I dont use EC very much on camera.


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## jcdeboever (Mar 9, 2016)

Ysarex said:


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OK.

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## jcdeboever (Mar 9, 2016)

pixmedic said:


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Oh, I see. I was using wrong terminology. It is EC. Now I can search forum for details. Thank you all.

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## jcdeboever (Mar 9, 2016)

Duh... I feel stupid. Lol

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## Designer (Mar 9, 2016)

jcdeboever said:


> What are some scenarios that would warrant a decision to under expose or over expose in camera using digital or film?


In the olden days of film, it was said that you should "expose for the shadows", meaning; make sure you get some usable image in the shaded parts of the frame.  

With digital, if you blow out the highlights, you are left with no data in the highlights, so I would rather underexpose a bit with digital.  (average scenes)

For shooting random scenes with a digital camera, you can take meter readings off the highlights, and work toward the shadows, bracketing a few shots.  

If it's a dark scene, meter the most important parts.

For very bright scenes you would want to underexpose, particularly if you are using "averaging" metering because the meter will attempt to expose for an average scene, and it will end up way too bright, often blowing the highlights.  

Unless I'm wrong.


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## jcdeboever (Mar 9, 2016)

Designer said:


> jcdeboever said:
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Excellent, thanks. OK, now what Hedgecoe was talking about is making more sense. Appreciate it. Very hard to articulate when I don't have a clear understanding of the whole exposure triangle and various metering modes in cameras. 

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## Dave442 (Mar 9, 2016)

I have to think you are referring to the exposure reading as given by the camera. You often need to adjust that to arrive at what you consider the correct exposure. 

I recently shot some singers outside under a tarp with a background of sky at the beach. I could have spot metered, but it was easier to just open up the lens a couple stops to give good exposure of their faces. Even spot metering would have required an adjustment to the exposure.  Then later I did some shots of a palm tree with the blue sky as a background and dropped the exposure a bit to not blow out the sky and have more of a silhouette of the tree. 

I am in manual and just set the exposure where I want it, usually not what the matrix meter is giving. If using Auto-ISO will hit the EC button and dial in how much compensation I want. 

Sometimes there is something throwing off the camera meter and you can get a meter reading without that in the frame and then consider that exposure reading with the one for the final composition and use that to come up with an idea of how much compensation to use. 

An example is to go take a picture of a white sheet of paper, none of the exposure modes will give you the correct exposure and you will need to increase the exposure given by the camera (my Genius Scan App on the phone  is smart enough to know to make this exposure adjustment automatically).


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## Ysarex (Mar 9, 2016)

jcdeboever said:


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jcdeboever said:


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You're not going to encounter Hedgecoe writing about the exposure triangle. He managed to take photos and understand exposure before the exposure triangle was invented.

Joe


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## jcdeboever (Mar 9, 2016)

Ysarex said:


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Right, reason for confusion because they were written long ago and I am trying to merge it with digital era and terminology. Additionally, terminology gets a little overwhelming in that manufacturers call their metering system different thing but basically perform same functions. So studying exposure triangle, I have stumbled across EC but I called it over/ under exposure which was wrong. I am now moving in the right direction as I was searching the wrong term. 

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## Ysarex (Mar 9, 2016)

jcdeboever said:


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There's a lot of confusion and misunderstanding when it comes to digital era terminology no less than that exposure triangle. There may be a good reason John Hedgecoe never needed it. I'll bet he defined exposure as the amount of light striking the film as a function of shutter speed and aperture (adjusted relative to the ambient light intensity). Has switching from film to digital sensors changed that?

Joe


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## jcdeboever (Mar 9, 2016)

Ysarex said:


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No change as I understand it. I was confusing exposure and exposure compensation. I try to get he exposure  center on either type of camera. So meter mode, what to meter, and how to adjust is direction I am now looking into. Also gaining a better understanding how each of my cameras meter would help. Thanks for your patience in my ignorance.  

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## JacaRanda (Mar 9, 2016)

What ever you do, don't make it harder than it is.  Sounds simple eh!


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## GHK (Mar 11, 2016)

jcdeboever said:


> What are some scenarios that would warrant a decision to under expose or over expose in camera using digital or film? Hopefully this is not too generic of a question.
> 
> Sent from my XT1254 using Tapatalk


A)   I can't really envisage a situation in which I would want to make a positive decision to do either.
B)   Factors in making exposure decisions are different for film and digital.   For film, they are different for negatives and transparencies, and are firmly based in the generalisations 'expose for the shadows' - neg, and 'expose for the highlights' - trans.
C)   With digital, things are a little easier because modern sensors have a greater dynamic range than film.
In those cases in which the tonal range in the subject is still too great for the sensor the advice is to expose for the shadows.   This is because the sensor response to light is linear, resulting in the recording of much less information in the shadow areas compared to the highlights.
When the sensor can fully record all the tones of the image, there can be a number of exposure levels which are nominally all correct (I am not referring to exposure time/ aperture combinations here).   In these cases the histogram levels will all display real tones as opposed to some tones being piled up at the 0 and 255 levels.   In such cases an exposure should be chosen which places the displayed levels as far to the right as possible without overshooting up the 255 axis.   The reason for making this choice is, as above, because of the linear response of the sensor.
GHK


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## Ysarex (Mar 11, 2016)

GHK said:


> jcdeboever said:
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Isn't "nominally correct" one of those oxymoron figures of speech like military intelligence, compassionate conservatisim, jumbo shrimp, etc.?

Joe


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## jcdeboever (Mar 11, 2016)

Ysarex said:


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Ha ha... Like Microsoft works, clearly confused, pretty ugly... Lol

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## Gary A. (Mar 11, 2016)

In your case JC, exposure starts with the light meter.  So let's look at the meter.  All meters read for medium gray (period). Spot meters only read a very small area of the frame, an average meter reads across the entire frame, center-weight reads more from the center than the surrounding edges, matrix/evaluative metering divides the frame up into many segments then does an analysis of each segment and then looks at the focus point and adds additional importance to the focus point segment and then compares its solution to a database of solutions.

Back to simple, what does metering for medium gray truly means?  It means if you fill the frame with a white wall, center the needle, take a snap and then make a print without any post processing manipulations ... you will end up with a medium gray image. Similarly, if you fill the frame with a black wall, center the needle, take a snap and then make a print without any post processing manipulations ... you will again end up with a medium gray image.

Arguably, it is up to the photographer to determine the final/proper/correct exposure using the meter as a guide and determining what mode matches up with the particular scene/subject that you are determined to capture.

If you're shooting a subject which is lighter than medium gray, (sometimes/typically referred to as 18% reflective gray), then you need to overexpose from what the meter is suggesting to obtain a final/proper/correct exposure.  

If you're shooting a subject which is darker than medium gray, (sometimes/typically referred to as 18% reflective gray), then you need to underexpose from what the meter is suggesting to obtain a final/proper/correct exposure. 

How much to underexpose or overexpose from the suggested meter reading is determined by the subject and the photographer.  

Landscape photogs will often take many spot reading from different areas and determine an exposure middle ground or average from all the various readings. 

A news photog may just read of the principal subject and determine a proper reading off the face, (a person of color will be underexposed and a white person will be overexposed), and not giving a rat's to the rest of the frame as long as the photog captures the main subject/the story.

There are aids to help determine a correct exposure, gray cards, incident light meters, matrix/evaluative modes, et cetera. But it all starts with medium gray and understanding how the meter works. 

(Reading material "The Negative" by Ansel Adams, is a very good starting point.)


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## Gary A. (Mar 11, 2016)

PS- As you seem to have a penchant for B&W, the Adam's Zone System may be particularly useful and interesting.


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## jcdeboever (Mar 11, 2016)

Gary A. said:


> PS- As you seem to have a penchant for B&W, the Adam's Zone System may be particularly useful and interesting.


Is that kind of like curves in photo editing software?

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## Gary A. (Mar 11, 2016)

jcdeboever said:


> Gary A. said:
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Actually it is an exposure methodology, with film and digital you have a range of Zones the film and digital sensor can capture (Dynamic Range).  For discussion purposes, if you're ... say ... shooting a landscape with ten different Zones and your film/sensor can only capture five zone, then you pick a Zone, (as an example), close to the Zone reflected by your principal subject, (say a barn at Zone 4), then if you expose for Zone 4, Zones 2, 3, 5 and 6 will fall within the dynamic range of the film/sensor ... et cetera.


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## Gary A. (Mar 11, 2016)

PS- With dynamic range increasing, ISO-less sensors, modern post processing programs, the Zone System is rapidly losing converts, but it is  a great place to learn and understand exposure and metering.


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## unpopular (Mar 11, 2016)

You're looking at it the wrong way. The question isn't "when to under expose", but rather, what is "under exposed" in the first place?


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## GHK (Mar 12, 2016)

Ysarex said:


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I don't think so; in the circumstance mentioned, there is not just one exposure that can be said to be 'THE correct one".   I am suggesting that, from the 'correct' range, one can be selected which gives advantages over the rest for the stated reasons.   Please come back if I am not making myself clear enough.
GHK


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## unpopular (Mar 12, 2016)

The only "correct" exposure is middle grey. That's it. That's the only objective place where the camera and the sensor or film can agree on.

Every image has regions of "proper" exposure - and this is the important part.

A photograph isn't "properly exposed". There will be regions that are under exposed (areasless than middle grey) and regions that are over exposed (areas greater than middle grey). I suppose an "under-exposed" image is one where the entire data set is less than middle grey.

Perhaps under exposure is when middle grey is rendered at a lower value. But there are MANY times, if not more times than not, that this might be the case, such as getting detail in clouds or to obtain a silhouette.

This kind of goes back to "what is under exposure". I wasn't being smart when I suggested that people think about it. Because when you try to objectively say "under exposed is when..." you simply can't, at least not in a way that is particularly helpful - such as saying "when all the image data is less than middle grey".

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This would be assuming, of course that you're shooting SOOC - where the final exposure is a close representation to the image.


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## jcdeboever (Mar 12, 2016)

I appreciate all the feedback and apologize for the using the wrong terminology in the beginning. I will run with studying the zone system and see if I can improve my exposures in camera. I believe that is where I need to go.


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## Gary A. (Mar 12, 2016)

jcdeboever said:


> I appreciate all the feedback and apologize for the using the wrong terminology in the beginning. I will run with studying the zone system and see if I can improve my exposures in camera. I believe that is where I need to go.


Understanding how your tools work and how best to use them in a given situation, is an important step to being able to previsualize photographs and then successfully capture your previsualization.


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## dennybeall (Mar 12, 2016)

My 2  1/2 cents -
There is correct exposure to document a scene, then there is correct exposure for artistic reasons. To document you may want to take multiple photos and then merge the properly exposed parts in post processing. Like a room with outside windows you take one exposure correct for the interior and one correct for the much brighter windows, then merge in Photoshop.

For artistic reasons there is no right or wrong, it's whatever the photographer wants.

Also, some cameras typically under or over expose so you set exposure compensation to fix that.

The point with the older B&W photographers was they talked about changing film for a different ASA while we now have changing the ISO of the camera to serve that purpose.


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## Ysarex (Mar 12, 2016)

GHK said:


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OK, not clear enough.

Originally you referred to a "number of exposure levels which are nominally all correct..."

Now you say, "there is not just one exposure that can be said to be "THE correct one".

Those two statements seem to say the same thing: more than one exposure can qualify simultaneously as "correct" -- equivocation maybe?

But then you say, "from the 'correct' range, one can be selected which gives advantages over the rest for the stated reasons", which certainly sounds like a contradiction of the above. If *ONE* can be selected which gives advantages over the rest wouldn't that be the correct exposure? Doesn't that contradict saying, "there is not just one exposure that can be said to be "THE correct one".

Here's a list of synonyms copied from the dictionary for the adjective correct:
right
accurate
true
exact
precise
unerring
faithful
strict
faultless

So here's a question: When taking a photo, is there *an exposure *(singular term there) that will produce the best possible IQ in the final photo, or best realize the photographer's intention? If so, isn't that the correct one?

Joe


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## KenC (Mar 12, 2016)

Ysarex said:


> When taking a photo, is there *an exposure *(singular term there) that will produce the best possible IQ in the final photo, or best realize the photographer's intention? If so, isn't that the correct one?



I agree that what will best realize one's intention is the "correct exposure" but for any given scene there can be more than one "correct" exposure depending on who is photographing it.  This is an example of a photograph deliberately overexposed in camera, meaning that EC was used to expose a couple of stops more than the meter recommended, then it was processed further, e.g., to even out the lighting and for other reasons:




 

If someone else had been there with a camera and wanted a "normal-looking" photo of my cat the "correct" exposure for them would have been very different.


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## jcdeboever (Mar 12, 2016)

KenC said:


> Ysarex said:
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Very helpful.

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## Ysarex (Mar 12, 2016)

KenC said:


> Ysarex said:
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And of course the same applies when I play my violin or guitar way out of tune. I just say it's the way I want it and so that makes it actually in tune. You can check it with a tuning fork to demonstrate that it's correctly out of tune in tune. 

Joe


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## GHK (Mar 13, 2016)

Ysarex said:


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I agree fully with your final statement/question.   My post was intended to direct attention to *THAT exposure*, whilst pointing out that there could well be others which were nominally correct according to standard criteria as well as those that were definitely defective.
GHK


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## kroyer (Mar 15, 2016)

jcdeboever said:


> What are some scenarios that would warrant a decision to under expose or over expose in camera using digital or film? Hopefully this is not too generic of a question.
> 
> Sent from my XT1254 using Tapatalk



Generally. I'll expose my shots to the mood I'm looking for and avoid my shadows and highlights loosing details.
That said. I'd prefer to overexpose a tad rather than underexpose as lightning an underexposed image brings out more noise.
In film I belive the opposite was the case as the highlights tended to blowout easier and there were more details in the darker areas.


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## Gary A. (Mar 15, 2016)

I think that high dynamic range, detail in the highlights and detail in the shadows is overrated in general and more so when shooting people/photojournalistic type photos.





Film- Nikon F2 w/Tri-X





Digital- Canon 1DsMKII


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## jcdeboever (Mar 15, 2016)

Dang, those are awesome. Nominated 2nd one Mar POTM. Best photo I have seen on here. 

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## unpopular (Mar 15, 2016)

Gary A. said:


> I think that high dynamic range, detail in the highlights and detail in the shadows is overrated in general



I don't think the problem is with dynamic range, I think it depends on what you're doing. These images wouldn't make sense with long exposure range, though I think it is taken a bit too far IMO.

Some filmmakers in particular are pretty amped about all this new-found dynamic range and feel the need to use every ounce of data captured with equal importance.

Now I love lots of detail. But shadows should be dark and hilights should be bright. That doesn't mean you need to go clipping everything out, but it does take a fair amount of finesse.


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## Gary A. (Mar 15, 2016)

I can see the desire for detail, as a general rule, for commercial/studio, architectural, landscape work, but for many other genres too much detail dilutes the story. (The above are extreme examples of not diluting.)


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## DanOstergren (Mar 16, 2016)

I have a habit of under exposing my images and then adjusting them in post to slightly intensify the highlights. I prefer lower key images and moody soft lighting with deep shadows, and I believe slightly under exposing (from what the meter on my camera usually tells me is "correct") lets me capture the image so that it's closer to what I am seeing for the final look in my head.


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## GHK (Mar 16, 2016)

unpopular said:


> Gary A. said:
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## tiaphoto (Mar 16, 2016)

I think its warranted to have underexposed or overexposed images if it fits your project. It's normally safer to get the best neutral exposure possible and then play around creatively in post. However, if  your style is having overexposed photos, for example; then it should be fine to overexpose them a little. Plus when you over expose, its easier to pull information back into the image vs when underexposed.


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## Tim Tucker (Mar 16, 2016)

It is incorrect to think in terms of a 'correct' exposure, but there is an optimum, or baseline exposure. Exposure is all about understanding how your media reacts to different levels of light, then using that to produce the results you want.

It is correct to think that there is a range of exposures, but incorrect to think that you can vary the exposure and correct the results. Every subject has a range of luminance, your whole image depends on there being a range of luminance that produces a variation in reaction on your chosen media in every exposure. If you vary the exposure you vary the reaction in your chosen media and it is a mistake to think that the tools at your disposal will allow you to make exposure 'A' look identical to exposure 'B'. They don't. In following a separate route to a result you invariably end up with a different result. It is in the understanding of how the media reacts to different levels of light and how varying this changes the results that is the heart of understanding exposure.

This is also key to understanding the Zone System. What Ansel Adams did was to first give you the optimal exposure and performance of film by establishing true film speed and optimum development. He then went on to show the effects of varying both the exposure and development of the film. Optimum is your baseline, it translates exposure to specific densities in the negative and from there to specific tones in the print. It must not be forgotten that the zones refer directly to tones in the print and not subject luminance. In giving you a baseline and a means of visualising it he also gave you the reference by which to view variations in exposure and development.

In B&W negative film you must first establish the true film speed (or crib Ansel's notes freely given at the back of his book "The Negative"). The film speed is the level of light needed to produce the first measurable change in density on the negative. Now on your negative the shadows produce very little change in the density of the film but your highlights being near maximum density produce maximum change in the density of the negative. So changes in development will have little to no effect where there is little development (shadows) but a big difference where there is a lot of development in the negative (highlights). So knowing where that baseline is is quite important with film. Film speeds on boxes and development times are a compromise. They allow speed and contrast at the expense of shadow detail and grain size. Basically you underexpose the film and over-develop, making the highlight areas more dense but producing little change in the shadows which remain under-exposed. This is what you need to understand with exposure and the Zone system, that you need to calibrate the threshold and the other end of the spectrum to finished tones in your print. It was never a guide to exposure but a visualisation and understanding of the whole process. This can be transferred to digital, understand and visualise your baseline and understand how the variations in exposure and processing change your result.


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## Ysarex (Mar 16, 2016)

Tim Tucker said:


> It is incorrect to think in terms of a 'correct' exposure, but there is an optimum, or baseline exposure. Exposure is all about understanding how your media reacts to different levels of light, then using that to produce the results you want.



How is optimum different from correct? You presented optimum exposure as a singular event precluding the existence of two or more different optimum exposures. But you say there is no correct exposure. Optimum sure sounds like correct to me. Is there a singular exposure that will produce either the best possible IQ and/or best realize the photographer's intention?



Tim Tucker said:


> It is correct to think that there is a range of exposures, but incorrect to think that you can vary the exposure and correct the results. Every subject has a range of luminance, your whole image depends on there being a range of luminance that produces a variation in reaction on your chosen media in every exposure. If you vary the exposure you vary the reaction in your chosen media and it is a mistake to think that the tools at your disposal will allow you to make exposure 'A' look identical to exposure 'B'. They don't. In following a separate route to a result you invariably end up with a different result.



In one of the following two photos the camera sensor received 400% more exposure than in the other (check EXIF). 400% is two full stops. Can you point out in what ways they do not look identical?










Here are the two histograms for the above two photos:








Tim Tucker said:


> It is in the understanding of how the media reacts to different levels of light and how varying this changes the results that is the heart of understanding exposure.
> 
> This is also key to understanding the Zone System. What Ansel Adams did was to first give you the optimal exposure and performance of film by establishing true film speed and optimum development. He then went on to show the effects of varying both the exposure and development of the film. Optimum is your baseline, it translates exposure to specific densities in the negative and from there to specific tones in the print. It must not be forgotten that the zones refer directly to tones in the print and not subject luminance. In giving you a baseline and a means of visualising it he also gave you the reference by which to view variations in exposure and development.
> 
> In B&W negative film you must first establish the true film speed (or crib Ansel's notes freely given at the back of his book "The Negative"). The film speed is the level of light needed to produce the first measurable change in density on the negative. Now on your negative the shadows produce very little change in the density of the film but your highlights being near maximum density produce maximum change in the density of the negative. So changes in development will have little to no effect where there is little development (shadows) but a big difference where there is a lot of development in the negative (highlights). So knowing where that baseline is is quite important with film. Film speeds on boxes and development times are a compromise. They allow speed and contrast at the expense of shadow detail and grain size. Basically you underexpose the film and over-develop, making the highlight areas more dense but producing little change in the shadows which remain under-exposed.



How can you underexpose if no correct exposure exists in the first place to underexpose from?



Tim Tucker said:


> This is what you need to understand with exposure and the Zone system, that you need to calibrate the threshold and the other end of the spectrum to finished tones in your print. It was never a guide to exposure but a visualisation and understanding of the whole process. This can be transferred to digital, understand and visualise your baseline and understand how the variations in exposure and processing change your result.



The Zone System does not transfer to digital. Reason number 1: Digital has no corollary to the chemical development process. There is no N+ or N-- development option with digital. You could try and simulate that but for heaven's sake why. All that would do is unnecessarily cripple the digital process to no advantage. Dropping your SD card in a tank of HC-110 is a bad idea. Reason number 2: See those two photos above.

Joe


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## Tim Tucker (Mar 16, 2016)

Ysarex said:


> How is optimum different from correct? You presented optimum exposure as a singular event precluding the existence of two or more different optimum exposures. But you say there is no correct exposure. Optimum sure sounds like correct to me. Is there a singular exposure that will produce either the best possible IQ and/or best realize the photographer's intention?



Optimum exposure is a baseline reference.




Ysarex said:


> In one of the following two photos the camera sensor received 400% more exposure than in the other (check EXIF). 400% is two full stops. Can you point out in what ways they do not look identical?



Sure they look identical and were processed to look the same. But this is not easily achieved and definately not possible in many circumstances (certainly not with film), so it's always better to approach exposure along the lines of giving a different exposure will produce a different result.



Ysarex said:


> How can you underexpose if no correct exposure exists in the first place to underexpose from?



This is why you have the baseline reference, a point to which exposure is greater or less than. I think you take me too literally here and argue yourself in circles. How can you talk about under and over exposure if you don't select a baseline reference to which you make the comparison? There will be an optimum exposure, sometimes more than one, that will give the best IQ and colour rendition or the "best balance" between grain, contrast and DR. You then understand the effects of giving more or less exposure by comparing you baseline reference.



Ysarex said:


> The Zone System does not transfer to digital. Reason number 1: Digital has no corollary to the chemical development process. There is no N+ or N-- development option with digital. You could try and simulate that but for heaven's sake why. All that would do is unnecessarily cripple the digital process to no advantage. Dropping your SD card in a tank of HC-110 is a bad idea. Reason number 2: See those two photos above.
> 
> Joe



I totally agree with you, the Zone System as in the zones themselves does not transfer to digital. _But the idea that you study your medium and how it reacts to different levels of light is transferable, and to do that you need a reference to call 'normal', a scale by which you measure differences._ That you use optimum IQ as your baseline does not mean that it's your goal in exposure. How do you express, "I want deeper and darker," if you don't have something it's deeper and darker than?
The whole concept then is that you learn how changing exposure produces different results, you study how to produce different results, not how to make different results look the same which I find a pointless exercise.

If I separate my last statement from the Zone System then my intended meaning may become clearer:



Tim Tucker said:


> It was never a guide to exposure but a visualisation and understanding of the whole process. This can be transferred to digital, understand and visualise your baseline and understand how the variations in exposure and processing change your result.


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## Ysarex (Mar 16, 2016)

Tim Tucker said:


> Ysarex said:
> 
> 
> > How is optimum different from correct? You presented optimum exposure as a singular event precluding the existence of two or more different optimum exposures. But you say there is no correct exposure. Optimum sure sounds like correct to me. Is there a singular exposure that will produce either the best possible IQ and/or best realize the photographer's intention?
> ...



You didn't answer my question: Is there a singular exposure that will produce either the best possible IQ and/or best realize the photographer's intention?



Tim Tucker said:


> Ysarex said:
> 
> 
> > In one of the following two photos the camera sensor received 400% more exposure than in the other (check EXIF). 400% is two full stops. Can you point out in what ways they do not look identical?
> ...



It was easy, however you're right it would have been impossible using film. But the OP has a digital camera and it is possible. You said it wasn't. Just making the point you're incorrect about that because it get's to how digital is different than film and the Zone System doesn't apply to digital.

I should have left the Zone System topic alone here and skipped the photo example, but it's so misunderstood and misapplied. Unfortunately it's a source here for further confusion.



Tim Tucker said:


> Ysarex said:
> 
> 
> > How can you underexpose if no correct exposure exists in the first place to underexpose from?
> ...



I'm trying to help you unravel your circles.



Tim Tucker said:


> How can you talk about under and over exposure if you don't select a baseline reference to which you make the comparison? There will be an optimum exposure, sometimes more than one, that will give the best IQ and colour rendition or the "best balance" between grain, contrast and DR. You then understand the effects of giving more or less exposure by comparing you baseline reference.



You just said there will sometimes be more than one optimum exposure. This is talking in circles; optimum is a superlative. A synonym for optimum is best. A superlative is by definition singular -- you can't have more than one optimum. 



Tim Tucker said:


> Ysarex said:
> 
> 
> > The Zone System does not transfer to digital. Reason number 1: Digital has no corollary to the chemical development process. There is no N+ or N-- development option with digital. You could try and simulate that but for heaven's sake why. All that would do is unnecessarily cripple the digital process to no advantage. Dropping your SD card in a tank of HC-110 is a bad idea. Reason number 2: See those two photos above.
> ...



Good place to ask my question again that you didn't answer before: Is there a singular exposure that will produce either the best possible IQ and/or best realize the photographer's intention? You want deeper and darker, notice how my question made allowance for that: best possible IQ and/or best realize the photographer's intention.

SIMPLE: You see something you want to photograph. You have a goal to achieve the best result possible. This can include what you want to express like deeper and darker. It can also include the IQ characteristics that the discipline has identified as desirable. *Any old exposure will do? Yes or no? If no, then isn't there a best, optimum, or correct exposure that will produce your goal?* 

Joe



Tim Tucker said:


> The whole concept then is that you learn how changing exposure produces different results, you study how to produce different results, not how to make different results look the same which I find a pointless exercise.
> 
> If I separate my last statement from the Zone System then my intended meaning may become clearer:
> 
> ...


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## Tim Tucker (Mar 17, 2016)

Ysarex said:


> It was easy, however you're right it would have been impossible using film. But the OP has a digital camera and it is possible. You said it wasn't. Just making the point you're incorrect about that because it get's to how digital is different than film and the Zone System doesn't apply to digital.
> 
> I should have left the Zone System topic alone here and skipped the photo example, but it's so misunderstood and misapplied. Unfortunately it's a source here for further confusion.



But I so totally agree with you on this point. The Zone System in film is often misunderstood, and pointless when applied to digital.

To be clear because the original question was about exposure in digital _and_ film: The Zone System for negative film was a method of visualisation, (in the days when you couldn't see the result straight after you pressed the shutter). It allowed you to see the process of exposure, development, and printing as a whole. It not only directly maps subject luminance to specific tones in the print, but allows you to visualise how changing exposure, development or both changes your result.

So what's wrong with applying the same philosophy to digital, in that we see the process as a whole and experiment with changing parts of the process to see how it changes the final image? By using a _consistent_ approach to achieve the same result we can better understand how varying this changes the result, (as I keep saying and this is also a part of the ZS philosophy). I find it pointless in digital to use different routes to achieve the same result.

With your example I can't help thinking that you're using an exception to prove a point. It's a flat, static subject with limited DR and colour. You changed exposure by changing shutter speed and in most photography this does impact on the result.

It's immediately obvious, to anyone that tries, that the mapping of values such as skin tones to specific "zones" on your digital sensor's performance is a completely pointless exercise because digital editing allows you not only to change the values but also the relative relationship between values. Without these mid-tone placements digital exposure essentially becomes highlights and noise control and how this changes with ISO. You also have access to both view your exposure and considerable information about it which pushes visualisation to the effects of digital editing on the information which you see.

Do I have an optimum exposure that I use as my 'best IQ and colour rendition"? Yes, but don't assume that because I talk about the Zone System that I base this on the same model or that it is even a static model. All I'm saying is that in both film and digital you have to view the process as a whole (including the nature of light you're capturing), and have some consistency in your approach to see the effects of varying exposure. 

I don't understand how your specific question with it's yes/no answer applies to digital or the point I tried to make.  I certainly don't believe that an inconsistent approach of, "any exposure will do, I'll correct it later in post," gets you either the results you want or any sort of understanding of exposure.


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## Gary A. (Mar 17, 2016)

The Zone System was brought up, (by me), as a methodology to understand metering and exposure. Learning how the meter works and how metering relates to exposure may significantly help the novice better grasp the basics of photography and how to apply those basics in their photographs.


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## GHK (Mar 17, 2016)

[/QUOTE]

How is optimum different from correct?

Correct means correct - full stop.
The optimum value is a compromise; whilst not ideal,  it is the best available combination in the relevant circumstances.
"What you gain on the roundabouts you lose on the swings" refers to such a compromise situation.
GHK


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## jcdeboever (Mar 17, 2016)

Gary A. said:


> The Zone System was brought up, (by me), as a methodology to understand metering and exposure. Learning how the meter works and how metering relates to exposure may significantly help the novice better grasp the basics of photography and how to apply those basics in their photographs.



Thank you Gary. It has been very helpful so far. I have had a lot of "ah ha" moments reading it. The book is very interesting. It is a hard read but I am taking it slow. I am getting a little confused when I read the above posts between the two trading jabs. I will stick with the book. 

I will correct myself, not a hard read but very technical.


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## Tim Tucker (Mar 17, 2016)

jcdeboever said:


> Gary A. said:
> 
> 
> > The Zone System was brought up, (by me), as a methodology to understand metering and exposure. Learning how the meter works and how metering relates to exposure may significantly help the novice better grasp the basics of photography and how to apply those basics in their photographs.
> ...



I thoroughly recommend that book, and recommend you read both the full introduction and the full chapter on the Zone System, it will explain things far better than I can. But remember he is specifically discussing B&W negative material.


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## pixmedic (Mar 17, 2016)

The OP has informed me that his question has been sufficiently answered to his satisfaction and requested that his thread be closed, and before people start the reports and the complaints about me closing a thread, I have always done that for anyone who wants their own thread closed.


Sent from my SM-N900P using Tapatalk


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