Traditional 18% Grey Exposure

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Feiertag

Feiertag

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I have been wondering about this topic for a while now. Why haven't Nikon, Canon, Sony, et al, given all of us, an option to override the 18%, if and when we feel it is necessary? I think it would be more than beneficial in some cases. How hard can it be for the camera makers to make this a reality?

What do you think of this option?

This video is what prompted me to finally ask the question.
 
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Feiertag said:
I have been wondering about this topic for a while now. Why haven't Nikon, Canon, Sony, et al, given all of us, an option to override the 18%, if and when we feel it is necessary? I think it would be more than beneficial in some cases. How hard can it be for the camera makers to make this a reality?

What do you think of this option?
Click to expand...
You mean like exposure compensation?
 
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Feiertag said:
I have been wondering about this topic for a while now. Why haven't Nikon, Canon, Sony, et al, given all of us, an option to override the 18%, if and when we feel it is necessary? I think it would be more than beneficial in some cases. How hard can it be for the camera makers to make this a reality?

What do you think of this option?

This video is what prompted me to finally ask the question.
https://mail.google.com/mail/u/0/#inbox/KtbxLthlvfGRGBxwQmCxHdzMNQPFhkXTMg?projector=1
Click to expand...
I can’t see your video. What exactly do you mean by override the 18%? To me anyway, that is exactly what exposure compensation does, so I don’t understand your question at this point.
 
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Butlerkid said:
Maybe this will help.............
Click to expand...
Thanks, Karen. I have a fairly good grasp of the metering system and how it works. Black subjects turn to grey and white subjects turn to grey due to the 18%. I knew people wouldn't understand what I was referring to because you have to think out of the box to get it. Below is a copy of the site you mentioned.

Faults with 18% Grey​

It is important to note that the light meter has some limitations.


Your camera meter turns colors into tones of grey. But our world is not grey; it is full of colors. Thus, there will be instances when the camera will provide an incorrect interpretation of reflectance.

If you take a photo of a black wall, for example, your camera meter is likely to interpret your image as underexposed, even when its adequately exposed. The misinterpretation is because a black wall is twice as dark as grey. But your camera’s light meter doesn’t intrinsically know that. So, it will read your image’s overall reflectance as less than 18% and tell you that your image is underexposed.




Similarly, if you take a photo of a white wall, your camera meter will interpret your image as overexposed, even if its properly exposed. This is because a white wall is twice as bright as grey; it will have an overall reflectance higher than 18%.

When determining exposure using the light meter, consider the elements within your scene. In general, using 18% grey as a baseline works, but is not suited for every situation.
 
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Feiertag said:
Thanks, Karen. I have a fairly good grasp of the metering system and how it works. Black subjects turn to grey and white subjects turn to grey due to the 18%. I knew people wouldn't understand what I was referring to because you have to think out of the box to get it.

Faults with 18% Grey​

It is important to note that the light meter has some limitations.


Your camera meter turns colors into tones of grey. But our world is not grey; it is full of colors. Thus, there will be instances when the camera will provide an incorrect interpretation of reflectance.

If you take a photo of a black wall, for example, your camera meter is likely to interpret your image as underexposed, even when its adequately exposed. The misinterpretation is because a black wall is twice as dark as grey. But your camera’s light meter doesn’t intrinsically know that. So, it will read your image’s overall reflectance as less than 18% and tell you that your image is underexposed.




Similarly, if you take a photo of a white wall, your camera meter will interpret your image as overexposed, even if its properly exposed. This is because a white wall is twice as bright as grey; it will have an overall reflectance higher than 18%.

When determining exposure using the light meter, consider the elements within your scene. In general, using 18% grey as a baseline works, but is not suited for every situation.
Click to expand...
I think we all agree on that and use exposure compensation when the light meter is "fooled" by the scene.

We are wondering what you would replace 18% grey with that would be accurate in all situations.
 
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Butlerkid said:
I think we all agree on that and use exposure compensation when the light meter is "fooled" by the scene.

We are wondering what you replace 18% grey with that would be accurate in all situations.
Click to expand...
Well, when the light meter is fooled by the 18% rule, have the "option" to switch that off. It isn't replacing anything. It's just an added option to use if you wish. to see what the end results would be. If it doesn't work then go back to the regular system.
 
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Feiertag said:
I have been wondering about this topic for a while now. Why haven't Nikon, Canon, Sony, et al, given all of us, an option to override the 18%, if and when we feel it is necessary? I think it would be more than beneficial in some cases. How hard can it be for the camera makers to make this a reality?

What do you think of this option?

This video is what prompted me to finally ask the question.
https://www.youtube.com/watch?v=j8xQ8WiI7rk
Click to expand...
Your link is a hack — so do us a favour — make you point with world here.
In the mean time — what alternative to 18% gray are you proposing. If you have no reasonable proposal then……
 
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There has to be a reference point…and ANY reference point is going to be fooled in some situations. Neutral gray / 18% gray is a more or less universal standard; the majority of photographers know how to compensate for scenes that will typically result in over/under exposure. Unless I’m missing something, turning off the reference point would only make exposure more wildly speculative.
 
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Feiertag said:
Hack? Buddy, what don't you understand? Read the posts once again and then it might sink in. It isn't that complicated.
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The link in Post #1 does not go to a YouTube video.... Perhaps you could edit the post to correct the link? Yes, I think video link is posted in Post #8, but a lot of people will read the first post and try to click on that link.....

If the camera doesn't use 18% grey, what will it use in order to generate an image in the viewfinder or on the LCD?
 
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Perhaps we should refer to the Zone System where there are 10 gradations of light (zones) ranging from pure black to pure white.

The simplest use of this is for the photographer to decide what patch in their scene they want to be exposed to give 18% brightness, perhaps by spot metering said patch, and set the exposure for that. Then, each other patch in the scene will fall into its respective zone.

There might be a few books written about this. One by Ansel Adams comes to mind.
 
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Maybe I am naive on this topic, but isn't what you are describing just full manual mode? In that situation, I manually set the ISO, shutter speed and f-stop. When I hit the shutter that is what I get, just like in the olden days on 35mm film before I had a light meter. My knowledge, rules of thumb and guess work were used to get a properly exposed shot. Since this mode bypasses the light metering system, 18% gray should not play a role.

At least with the mirrorless cameras and EVF, one can see pretty much what the shot will look like. There is no reference to any grayscale because your are setting all of the parameters. If I am misunderstanding, let me know so I can reframe my thoughts.
 
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John Woodworth said:
Perhaps we should refer to the Zone System where there are 10 gradations of light (zones) ranging from pure black to pure white.

The simplest use of this is for the photographer to decide what patch in their scene they want to be exposed to give 18% brightness, perhaps by spot metering said patch, and set the exposure for that. Then, each other patch in the scene will fall into its respective zone.

There might be a few books written about this. One by Ansel Adams comes to mind.
Click to expand...
But the Zone system needs a light meter calibrated to 18% gray (or some reference) as a starting point. To the OP, I ask as others have, if you aren't using 18% gray for a reference point, what are you using? I suppose one could use the method we used to use back in the day when the light meter failed; sunny 16. In the old days, we could make an educated guess for exposure and get close. Sunny 16 saved my bacon on more than one occasion! You don't need to turn off the 18% gray reference to do that, just go full manual and ignore the meter. I still use an incident meter with large format but it's reference is 18% gray. Maybe I'm dense, but I'm not seeing any advantage to changing the reference point.
 
To throw another factor in, Canon, Nikon, etc. Don't use 18%. Closer to 12%, and actually the zone system originally instructed to tilt the 18% grey card 30 degrees off the light, so it essentially used 12% also.

Anyway, it's easy to not rely on the meter. If you have blinkies and or the histogram just find the highest non blinkie exposure and add 2/3 stop to that.
 
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Feiertag said:
When determining exposure using the light meter, consider the elements within your scene. In general, using 18% grey as a baseline works, but is not suited for every situation.
Click to expand...
Indeed.
The best way to do, is as done in cinematographic shooting or possibly in studio shooting :
Measure incident light and not reflective light.
But this imply having a dedicated cell, measuring light from the subject position (not the camera one), identifying key light and orienting the dedicated cell the good way for the measure make sense. And it implies too having tested the complete shooting chain before this to know what to set on the camera after this measure.

Measuring light from the subject position is often not possible, this is why we don't measure incident light but reflective light.
Here, you still can use spot meter function of your camera, measure the highlights, then the low lights, even middle tone of your image and then decide what is the best exposure for your scene.

But the fastest way on the field is to compensate what you see compared to a neutral gray. With practice it become easy.
 
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Of course my early cameras didn't always have light meters. In that case you'd find a paper wedded up in the film canister explaining the basics of exposure value and sunny 16. This is still useful information. The idea was/is to evaluate by eye the light falling on the scene and assign it a single number, a light value. Full sunlight on a cloudless day was a 15, but if the subject was bright it would be 16. A cloudy but bright day might be 13, sunset might be 12, and so on. At ISO 100, light value and exposure value were the same number, but as ISO changed the exposure value changed to compensate. So by a happy coincidence a shutter speed of 1/ISO at f 16 gave a good exposure for a sunny day. Equivalent exposures could be mentally calculated for any light value.

The good thing about that is one walked around with an awareness of what the light was doing and whether the subject was bright or dark.
 
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