Exposure compensation

[Barney]

In the old days when cameras started coming out that could take eight spot readings and average them out the joke was the result would always be 1/125 @ F8! It's a good place to start.

I thought it was just me who always started there. LOL

 

[droj]

More than one way to skin a cat. And as for the original question:

If I spot meter a scene and then lock it in with the exposure lock button, does the EV lock remain in place if I subsequently apply exposure compensation or will the compensation apply after the locked value has been identified.
Do I need to consider a specific order when selecting the EV lock or compensation?
My objective is to lock in the EV and then apply compensation to that previously metered value but not sure which to do first.
Nikon DSLR systems.

Dunno. My guess would be compensate first, then lock. But you could soon find out by doing some quick empirical tests at home before you go out - wouldn't take long & you'd only have to do it once to establish the principle. Come on, man - pull your finger out!

And once you feel that you're getting a successful result from your methodology, show us a pic? This thread has been great fun, so far ...

 

[Barney]

More than one way to skin a cat. And as for the original question:

Dunno. My guess would be compensate first, then lock. But you could soon find out by doing some quick empirical tests at home before you go out - wouldn't take long & you'd only have to do it once to establish the principle. Come on, man - pull your finger out!

And once you feel that you're getting a successful result from your methodology, show us a pic? This thread has been great fun, so far ...

OK Sherlock,

both have been posted here and each passed under the radar without incident or comment so it must be a crap idea anyway, Steven has it right, D4 will not, no matter what blow the highlights.. I have half a dozen cameras to test....

 

[myotis]

That is the thing Steven, I want some pushed off the scale but not everything in the scene "in that area" would be demolished.

My exposure compensation, D3s today, has five stops compensation either way.

without adjusting speed, aperture, which I could well be on the limit of for holding and dof effect, exposure compensation just seemed easier.

I'm pretty sure you can't use exposure compensation in manual mode, because with everything fixed there is nothing available for the exposure compensation to adjust. Certainly nothing changes with my Nikons or my Fujis when I turn the exposure compensation dial in manual.

With manual shutter and aperture, but with Auto ISO, the exposure compensation adjusts the ISO. But it's less optimal to adjust ISO rather than shutter or aperture

With aperture priority auto, it adjusts the shutter speed, and with,

Shutter priority auto, it adjusts the aperture.


Personally, I would forget the exposure lock and the exposure compensation, and decide what is the most important; aperture or shutter speed, and just manually set them where they give the effect you are after.

As an aside, you can't really get a Zone 3 shadow in the wild; you can only get a zone 3 shadow in a final image.

ie you look at the tonal range in the subject and decide where you want a particular tone, within the subject to "fall", when it's printed.

When you point the spotmeter at the area you want to look like zone 6, 7 or 8, on the print, the meter is still telling you the exposure to give Zone 5 on the print.

So 1 stop more than the meter reading will give Zone 6 on the print, 2 stops more, will give zone 7 and 3 stops more, will give you zone 8.

You can also estimate what will happen to the brighter areas of the scene by measuring them with the spotmeter and seeing what zone they will fall into once you have added this extra exposure.

In practise, this is more complicated, not helped by Nikons being calibrated for a 12% grey and not 18%, but the concept of where tones will fall in the final image is still useful when thinking about exposure, even if digital sensors don't behave the same way as film.

Have you done the standard zone system tests to see how your different sensors respond to different levels of exposure e.g. pictures of white towel given a range of exposure, at a stop apart, across a full range of Zones (below zone zero and above zone 11) based on the meter reading, to see what happens to detail retention and tone.

It's also worth emphasising that the zone system was developed for b&w negative film, whereas digital behaves more like colour positive film.

As a rule of thumb, with negative films you expose for the shadows and let the highlights look after themselves; with digital and positive film, it's the other way round and you expose for the highlights and let the shadows look after themselves.

This is rather simplified, but just as the zone system is a useful concept when thinking about exposure, so are these basic concepts of the differences between exposing for film and digital.

With digital, I see exposure as a much more technical exercise than it was with film and have an "optimise data capture" approach. Although it's not ideal, as it's a JPEG based histogram, I use the histogram to give the maximum exposure that avoids blowing out important highlights. if I get it right, this gives me the maximum amount of data possible for processing.

As far as I am aware, only Phase One cameras offer Raw histograms in-camera.

 

[Barney]

I'm pretty sure you can't use exposure compensation in manual mode, because with everything fixed there is nothing available for the exposure compensation to adjust. Certainly nothing changes with my Nikons or my Fujis when I turn the exposure compensation dial in manual.

With manual shutter and aperture, but with Auto ISO, the exposure compensation adjusts the ISO. But it's less optimal to adjust ISO rather than shutter or aperture

With aperture priority auto, it adjusts the shutter speed, and with,

Shutter priority auto, it adjusts the aperture.


Personally, I would forget the exposure lock and the exposure compensation, and decide what is the most important; aperture or shutter speed, and just manually set them where they give the effect you are after.

As an aside, you can't really get a Zone 3 shadow in the wild; you can only get a zone 3 shadow in a final image.

ie you look at the tonal range in the subject and decide where you want a particular tone, within the subject to "fall", when it's printed.

When you point the spotmeter at the area you want to look like zone 6, 7 or 8, on the print, the meter is still telling you the exposure to give Zone 5 on the print.

So 1 stop more than the meter reading will give Zone 6 on the print, 2 stops more, will give zone 7 and 3 stops more, will give you zone 8.

You can also estimate what will happen to the brighter areas of the scene by measuring them with the spotmeter and seeing what zone they will fall into once you have added this extra exposure.

In practise, this is more complicated, not helped by Nikons being calibrated for a 12% grey and not 18%, but the concept of where tones will fall in the final image is still useful when thinking about exposure, even if digital sensors don't behave the same way as film.

Have you done the standard zone system tests to see how your different sensors respond to different levels of exposure e.g. pictures of white towel given a range of exposure, at a stop apart, across a full range of Zones (below zone zero and above zone 11) based on the meter reading, to see what happens to detail retention and tone.

It's also worth emphasising that the zone system was developed for b&w negative film, whereas digital behaves more like colour positive film.

As a rule of thumb, with negative films you expose for the shadows and let the highlights look after themselves; with digital and positive film, it's the other way round and you expose for the highlights and let the shadows look after themselves.

This is rather simplified, but just as the zone system is a useful concept when thinking about exposure, so are these basic concepts of the differences between exposing for film and digital.

With digital, I see exposure as a much more technical exercise than it was with film and have an "optimise data capture" approach. Although it's not ideal, as it's a JPEG based histogram, I use the histogram to give the maximum exposure that avoids blowing out important highlights. if I get it right, this gives me the maximum amount of data possible for processing.

As far as I am aware, only Phase One cameras offer Raw histograms in-camera.

Thank Graham for your time and trouble for that superbly detailed and thorough reply, And explanation of the Zones!

Inspired after your post, even though my new flash lead has arrived and i want a play with it, I have started testing.........As you say, it appears that full manual exposure compensation will not work as there is nothing to adjust, in "S" mode with iso fixed and lens goes wide open wide open as possible and still no compensation beyond that. I think I would need a meter reading at F22 say a 1/60th to get there. Aperture mode with fixed ISO slows the shutter down lower than my capability to hand hold. It seems that ideally the exposure compensation needs two thing to combine enough to give Compensation result dialed in. Or set on tripod. Of course outside there will be tons more latitude than in my dingy living room,

At least I know how its working now.

 

[LeeRatters]

I try not use auto ISO in digital, unless the light is changing fast I am wide open and I can't keep up, a real advantage.

With my film shooting there is no auto, or metering. I work it out myself.

You don't? Since getting the A7Riii a few years ago & realising noise doesn't matter too much any more, I sit in Auto ISO [in Av mode] all the time unless I am tripod landscape/night sky shooting or want to shoot a panorama in full manual.

 

[ancient_mariner]

You don't? Since getting the A7Riii a few years ago & realising noise doesn't matter too much any more, I sit in Auto ISO [in Av mode] all the time unless I am tripod landscape/night sky shooting or want to shoot a panorama in full manual.

Barney wants it from the camera without adjustment.

 

[LeeRatters]

Barney wants it from the camera without adjustment.

I'm not 100% sure what's going on tbh But it's interesting reading in places

 

[droj]

With digital, I see exposure as a much more technical exercise than it was with film and have an "optimise data capture" approach. Although it's not ideal, as it's a JPEG based histogram, I use the histogram to give the maximum exposure that avoids blowing out important highlights. if I get it right, this gives me the maximum amount of data possible for processing.

Yes, me too, but I think that Wayne (the OP) is after something different to that, by his own admission? My assumption being that highlights were his sacrifices?

As far as I am aware, only Phase One cameras offer Raw histograms in-camera.

Gimme! Could crowdfunding be the way to get there?

 

[Eucris]

Well I'm absolutely baffled as to what it is that the OP is trying to do.

 

[Barney]

Yes, me too, but I think that Wayne (the OP) is after something different to that, by his own admission? My assumption being that highlights were his sacrifices?

That correct Droj, blowing an area of the scene is essential really, but there will be stuff within that blown out area that is not entirely destroyed. Its a fine line, thus my desire for an accurate repeatable approach.

 

[EdinburghGary]

Is this mainly a film or digital camera you want to solve this on? I would just use bracketing to capture a range of exposures and not care

Film? Well....get it nailed on digital and then transport the settings.

 

[Barney]

Is this mainly a film or digital camera you want to solve this on? I would just use bracketing to capture a range of exposures and not care

Film? Well....get it nailed on digital and then transport the settings.

Thats the one Gary, learn on digital transfer to film, the effect is better.

 

[droj]

But it has already been pointed out above that digital equates to positive film, and the exposure considerations for negative film are different, & something of a mirrored opposite ...

As for bracketing exposure - it might be a worthy technique, but who'd have the patience? Yes I know that these days it can be automated - but let's go for one shot, and take the risk. Trusting one's judgement is part of the frisson of photography to me, & I threw off the nappies years ago.

 

[LeeRatters]

That correct Droj, blowing an area of the scene is essential really, but there will be stuff within that blown out area that is not entirely destroyed. Its a fine line, thus my desire for an accurate repeatable approach.

But surely the amount of +EC required to do that is going to entirely depend on the actual scene in front of you and will change from scene to scene and day to day?

 

[mstphoto]

I do shoot in manual Mike, but I want to lock the EV at the value in that specific area and recompose. If I don't lock it every time I move about in the scene the exposure is recalculating at the release button.

I wouldn't have thought that, Barney
Once you've set your desired exposure manually, it shouldn't alter if you recompose

 

[myotis]

Thank Graham for your time and trouble for that superbly detailed and thorough reply, And explanation of the Zones!

Inspired after your post, even though my new flash lead has arrived and i want a play with it, I have started testing.........As you say, it appears that full manual exposure compensation will not work as there is nothing to adjust, in "S" mode with iso fixed and lens goes wide open wide open as possible and still no compensation beyond that. I think I would need a meter reading at F22 say a 1/60th to get there. Aperture mode with fixed ISO slows the shutter down lower than my capability to hand hold. It seems that ideally the exposure compensation needs two thing to combine enough to give Compensation result dialed in. Or set on tripod. Of course outside there will be tons more latitude than in my dingy living room,

At least I know how its working now.

Slightly confused here with the contradiction of "wide open" (a big aperture) but then you refer to the lens being stopped all the way down to f16 (ie a small aperture).

In a really dingy room, the 1/60s ( I assume that is the shutter speed needed for flash sync) might not be an issue for camera shake, as all the exposure is going to come from the flash and none from the ambient light.

So shutter speed becomes irrelevant to the exposure, and you just need to work with aperture and the flash power settings. If you need to open the aperture up a few stops from f22 to get the effect you want, and risk the ambient light affecting the image, make the room even dingier ie close the curtains to reduce the ambient light.

 

[Barney]

I wouldn't have thought that, Barney
Once you've set your desired exposure manually, it shouldn't alter if you recompose

I think I thought that EC was doing something different Mike, it is not.

EC is using the same tools that I more or less use without thinking in film, where I hit brick walls - Lens speed and holding capability, EC hits those the same brick walls. The exception is in the old digital camera models where ISO range is usable to 6-7 stops (depending on model obviously). The new camera models, from what I read, have massive 10+ stops of latitude.

 

[myotis]

Yes, me too, but I think that Wayne (the OP) is after something different to that, by his own admission? My assumption being that highlights were his sacrifices?

That might be the consequence, but not sure if it was part of the intent. EDIT: I see in a later reply from the OP, that he is still trying to maintain subtle details in the highlights, but accepts that some might be lost, which is why he is trying to get precise control over where he pegs the exposure.

Gimme! Could crowdfunding be the way to get there?

Yes, though I would have thought it possible to get a better representation of raw in other cameras by customising the film emulations/picture controls used in camera.

The argument I've heard against this is that while a raw preview will allow a better assessment of exposure, it give a poor representation of what the final processed image will look like, which is always contrastier, brighter and more saturated than the linear representation of the raw data needed to assess the raw exposure.

I think Phase One has a raw histogram, but a processed preview.

 

[Eucris]

I see in a later reply from the OP, that he is still trying to maintain subtle details in the highlights, but accepts that some might be lost, which is why he is trying to get precise control over where he pegs the exposure.

And in post #4 he said the following.

If I spot meter a black shadow area where I need to emphasize a rich dark detailed area, I do not want it averaged out to grey.

 

[Barney]

And in post #4 he said the following.

I thought that was the best way to try and explain it as kinda no one seemed to understand, if you want try and prove I am an idiot - ok I am an idot.

END

 

[mstphoto]

I always bracket my landscape shots and blend them in Photoshop.
OR, if your overall exposure is good but you're not happy with the shadow area, you can make a selection of the shadow and alter that without altering the whole image.
I hope you get your problem solved.
I know how infuriating it can be

 

[LeeRatters]

I thought that was the best way to try and explain it as kinda no one seemed to understand, if you want try and prove I am an idiot - ok I am an idot.

END

I don't think it's anything to do with being an idiot...... Maybe a mix up in terms used or explanations.

ie - you said quoted above - If I spot meter a black shadow area where I need to emphasize a rich dark detailed area, I do not want it averaged out to grey.

^ that pretty much means you need to under expose from the camera meter with a -EC setting. Yet there's lots of other talk about a +EC setting because you almost want to blow the highlights, which is the opposite.

And I think there's also a bit of manual vs Av confusion going on in this thread between responses.

I think people are commenting and trying to help out, but it's not fully clear what the issue is or what you want to achieve.

 

[Hanley]

It’s not ‘Manual’ if the camera is changing the exposure.

Have you fallen into the trap of thinking that M with auto ISO is Manual?

Manual is M without auto ISO.
Most camera manufacturers fell into auto ISO without a plan and it’s now confusing folk

This!!

Most manufacturers now offer a semi-automatic manual mode, which is basically what you're using, M with Auto ISO.
It's not a bad thing, in a lot of sports events I shoot it's a lifesaver to be honest, especially on days when there is sun + cloud cover and the light can change in an instant, when you don't have any time to check and change ISO having the semi-auto mode is a life saver.

I even go a step further by setting my camera's minimum shutter speed (1/1000 for running and other fitness events), set the camera to Apterture mode with auto ISO and I'm good to go, all I need to worry about is what F stop I want, single runner I turn the dial to f2.8, right behind them is a group of 4 runners, quick change of the dial to f5, I don't need to worry about motion blur as I know the camera will set the correct shutter speed but won't go below 1/1000 and it will use the ISO it needs to balance the exposure. Works perfectly in the scenarios I need it.

But I agree with what Phil says, for your scenario wouldn't you just set your ISO manually meaning you don't need to change anything as the exposure is always locked.

 

[ancient_mariner]

A reluctance to work in post doesn't help. With negative film photography an image always requires careful printing to get the best from it, and that's true for digital photos too. With film transparency work you have to choose your compromises, knowing you don't have control over different parts of the image.

 

[Eucris]

I thought that was the best way to try and explain it as kinda no one seemed to understand, if you want try and prove I am an idiot - ok I am an idot.

END

Just post an image and then explain what it is that you want to do to that image. That way people will be able to help you without having to second guess what you mean.

 

[Barney]

A reluctance to work in post doesn't help. With negative film photography and image always requires careful printing to get the best from it, and that's true for digital photos too. With film transparency work you have to choose your compromises, knowing you don't have control over different parts of the image.

Hi Toni,

you may have directed me to another area of investigation............ first..........I have not been in a darkroom so apologies if my comments seem nonsensical..

When you are developing from the negative can you see the effect on the print while you are dodging and burning?

Is it instant kind of thing or is there some kind of delay between what you see and the finished article.

 

[Terrywoodenpic]

You could not be more wrong there Phil, with respect and no offense intended.

I have selected a method I want to use and would like to bend the camera's functionality to my requirements.

If I spot meter a black shadow area where I need to emphasize a rich dark detailed area, I do not want it averaged out to grey.

If you spot meter a black area you will end up with a lighter overall image.
Unfortunately spot metering is still taking an average exposure , just over a much smaller area.

To get every tone where it lays on a scale of black to white, the only way is to take an incident light reading either with a dedicated meter or by taking a camera reading from a grey card, or perhaps equally well, from the palm of a hand, that is in the same light as the subject.

There have been cameras that allowed you to take individual highlight and shadow through the leans readings, and derive a correct exposure (what ever that means) the best was perhaps the Olympus OM3 and 4..
As far as I know no digital camera has this facility.

Spot metering will always try to expose the area read, as a neutral mid grey. It does not know,nor care, if it is reading is a shadow or highlight.

Exposure lock does just that, it locks the shutter speed, aperture and ISO. at the last settings, what ever that happens to be. And for as long as the lock is maintained.
It's most useful function is for use when taking panoramas and the like. Where images must match over the entire set.
It is also useful when taking against the light shots when you can establish a correct exposure and lock it so that follow up shots are not influenced by the back light in random ways. [Wedding come to mind]

The easiest way For you to get the right distribution of tones including blacks, is by using a matrix reading then chimping the result and adjusting accordingly.
Checking the histogram will show you the distribution of tones and allow you to favour the highlights or shadows.

 

[Terrywoodenpic]

Hi Toni,

you may have directed me to another area of investigation............ first..........I have not been in a darkroom so apologies if my comments seem nonsensical..

When you are developing from the negative can you see the effect on the print while you are dodging and burning?

Is it instant kind of thing or is there some kind of delay between what you see and the finished article.

You do not see the result of dodging and burning on the undeveloped paper. This only become apparent on development

Printing is a whole other world to digital. I started printing in the 1940's and it became second nature to dodge and burn
However using the dodge and burn tools in digital is far easier as you can see what you are doing. However extreme dodging and burning in digital does Change the colours in nasty ways unless you change the image to lab colour and do it on the correct (lightness) layer. Not many people seem to know that????

 

[ancient_mariner]

Hi Toni,

you may have directed me to another area of investigation............ first..........I have not been in a darkroom so apologies if my comments seem nonsensical..

When you are developing from the negative can you see the effect on the print while you are dodging and burning?

Is it instant kind of thing or is there some kind of delay between what you see and the finished article.

Good question. Normally one would print on a strip of paper using increasing different exposure times and develop it to see what the right average time would be. Nothing is visible until it is developed. Next you might make a flat print based on the test strip, again developing it. Third (or more) time you evaluate the flat print to see if it needs to be more or less dense, whether some parts need to be held back or darkened, then you make that print based on expectations.

You can see the negative image projected onto the paper, but the print is only visible after development.

It's not unusual to draw on the flat print, areas that need adjusting, often with a + or - and a value to indicate how much to adjust. This can also allow use of a softer, less contrasty grade of paper that allows more detail in bright and dark areas while maintaining a punchy image. Hand printing is as much an art as taking the picture originally.

 

[LCPete]

You do not see the result of dodging and burning on the undeveloped paper. This only become apparent on development

Printing is a whole other world to digital. I started printing in the 1940's and it became second nature to dodge and burn
However using the dodge and burn tools in digital is far easier as you can see what you are doing. However extreme dodging and burning in digital does Change the colours in nasty ways unless you change the image to lab colour and do it on the correct layer. Not many people seem to know that????

Oh I didn’t know that about lab colour, I don’t dodge and burn very often for that reason

 

[ancient_mariner]

One of the things On1 make a big deal over is maintaining the colours through exposure adjustments.

 

[Erty]

On a Nikon if you set the exposure lock to hold (so it toggles) the exposure lock adjusts with any subsequent +-ev setting. So exposure lock, take picture, review picture and adjust the exposure up and down, take lots of pictures and adjust as necessary. If you press exposure lock again it will toggle it off.

Easy and quite useful if the light is not changing.

 

[Graham W]

But that's not really how the Zone System was intended... it is meant to combine an exposure offset AND development offset in order to maximize/replicate the scene DR in the final image.

This...very much this! (And the reason I've not got invilved in this disscussion! )

 

[sk66]

With aperture priority auto, it adjusts the shutter speed, and with,

Shutter priority auto, it adjusts the aperture.

This assumes a fixed ISO... I.e. I often use aperture priority because the aperture is the only thing I care about specifically, and I let the camera figure out the other two. In that case (with auto ISO), the camera adjusts whichever variable is best (i.e. reduces ISO instead of increasing SS).

In practise, this is more complicated, not helped by Nikons being calibrated for a 12% grey and not 18%,

Photographic reflectance light meters have always been calibrated to ~ 12% gray. The Kodak 18% card was originally developed for printing (measuring/comparing print densities). But it turns out that it is close enough and became popular. It results in 1/2 - 1 stop underexposure if measured/used directly; but you were always supposed to use it more indirectly, i.e. increase the metered exposure by half stop for subjects of normal (avg) reflectivity (kodak pub. R-27).

Middle gray measures as 10% (the geometric/photographic mean of 1% and 100%); and the ISO (previously ANSI) standard includes a K factor of 1.16 for reflectance meters, which results in ~ 12% (it uses a different C factor for incidence meters). The standard does include some tolerance; it's not exact. And "the standard" isn't actually a requirement either... Sekonic uses 14%; and the Japanese CIPA standard only references generating an exposure comparable to what a handheld meter would result in (used in determining the ISO ratings of digital cameras).

I.e. 18% is ~ middle gray perceptually to a human. 10% measures as middle gray instrumentally. 10% + K factor is used for the ISO reflectance meter standard... if the standard is used. But all of this is basically just theoretical; because there is no such thing as "the correct exposure" for a photograph unless you first specify the intended result.

 

[Hanley]

This assumes a fixed ISO... I.e. I often use aperture priority because the aperture is the only thing I care about specifically, and I let the camera figure out the other two. In that case (with auto ISO), the camera adjusts whichever variable is best (i.e. reduces ISO instead of increasing SS).

In my experience, just from my own observations, when I set the 'Minimum Shutter Speed' on my Canon and then run in Aperture Priority mode, the camera will adjust the shutter speed (higher if the scene is very bright) and keep the ISO to base, but when it needs more light it will drop the shutter speed to whatever I set as minimum and then start increasing the ISO to get the correct exposure.

 

[sk66]

in "S" mode with iso fixed and lens goes wide open wide open as possible and still no compensation beyond that

That's the normal behavior unless you lock in an aggressively high ISO, which is a negative for images that don't require it. I.e. I almost never use shutter priority.

 

[sk66]

In my experience, just from my own observations, when I set the 'Minimum Shutter Speed' on my Canon and then run in Aperture Priority mode, the camera will adjust the shutter speed (higher if the scene is very bright) and keep the ISO to base, but when it needs more light it will drop the shutter speed to whatever I set as minimum and then start increasing the ISO to get the correct exposure.

Nikons behave the same. If auto ISO is set up "correctly", with min SS and min/max ISO limits set, in aperture priority the camera will make the same choices I would make; only quicker and more accurately.

I.e. it reduces ISO as long as it can achieve the required minimum SS set. When ISO reaches the minimum set it increases SS. When ISO reaches the max limit set, it will reduce the SS below the limit set; and it's time to change the aperture or shut down for the night.

 

[myotis]

This assumes a fixed ISO... I.e. I often use aperture priority because the aperture is the only thing I care about specifically, and I let the camera figure out the other two. In that case (with auto ISO), the camera adjusts whichever variable is best (i.e. reduces ISO instead of increasing SS).

My list of options wasn't exhaustive and I do the same as you when I'm using aperture priority; setting up the options in the preferences to help the camera decide what to do.

Photographic light meters have always been calibrated to ~ 12% gray. The Kodak 18% card was originally developed for printing (measuring/comparing print densities). But it turns out that it is close enough and became popular. It results in 1/2 - 1 stop underexposure if measured/used directly; but you were always supposed to use it more indirectly, i.e. increase the metered exposure by half stop for subjects of normal reflectivity (kodak pub. R-27).

Middle gray measures as 10% (the mean of 1% and 100%); and the ISO (previously ANSI) standard includes a K factor of 1.6 for reflectance meters, which results in ~ 12% (it uses a different C factor for incidence meters). The standard does include some tolerance; it's not exact. And "the standard" isn't actually a requirement either... the CIPA standard, which Japanese manufacturers use. only references generating an exposure comparable to what a handheld meter would result in (in determining the ISO ratings of the camera); and Sekonic uses 14%.

I.e. 18% is ~ middle gray perceptually to a human. 10% measures as middle gray instrumentally. 10% + K factor is used for the ISO reflectance meter standard... if the standard is used. But all of this is basically just theoretical; because there is no such thing as "the correct exposure" for a photograph unless you first specify the intended result.

And many people just measure a judged by eye "mid-tone", or a caucasion flesh tone, and give a stop more than suggested.

I had forgotten sekonic used 14%

One of the good things, I think, of going through the pain of learning, and then the satisfaction of applying, the zone system, is I can remember studying all of these things once upon a time.

On your last point, and I know not everyone agrees, I still find an underlying theoretical understanding is useful when trying to solve an otherwise inexplicable 'real world" photography problem.

 

[sk66]

One of the good things, I think, of going through the pain of learning, and then the satisfaction of applying, the zone system, is I can remember studying all of these things once upon a time.

On your last point, and I know not everyone agrees, I still find an underlying theoretical understanding is useful when trying to solve an otherwise inexplicable 'real world" photography problem.

I can't imagine not having learned, or wanting to learn, the theoretical/technical truths behind things these days... with today's complexity of equipment, and the flood of often poor/conflicting information, it would seem to be very confusing at times.

Although I find some knowledge is fading/blurring these days from lack of use...