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It seems to me there must be some kind of error in color calibration of most cameras. They make shadows much darker than they are, and bright areas much brighte

It seems to me there must be some kind of error in color calibration of most cameras. They make shadows much darker than they are, and bright areas much brighter than they are. It's not from a lack of dynamic range.

marban 5y ago
The error is the photographer. People just got used to ultra-correction of modern-day phone cams.
unfocussed_mike 5y ago
How is it not from a lack of dynamic range? Colour transparency film (e.g. Fuji Velvia -- RVP50) shows the same thing as clearly. You basically can't map real world light into the dynamic range of a typical camera without causing some of this experience, can you? The question is how you determine how dark shadows should be -- your brain is doing a lot of work to hide from you the tricks it uses to make shadows appear less dark than they might be with a linear response. Or even how they would look with a non-linear response that is even across the "frame"; your brain is doing localised dodge/burn type work, constantly. Camera manufacturers have "tastemakers" for this stuff on digital, just as film manufacturers used to have them for film.
- ElephantsMyAnus 5y ago
  It is different because it is obvious that shadows are darker than in reality while highlights are much brighter than in reality. Any brain filtering would have to affect the photos as well, even if it was true. No common image format uses linear response. It would explain this problem if cameras treat them as linear. Maybe they should just make the cameras take physically correct colors, instead of relying on people, as the typical person will always choose extreme contrast that will make the camera unusable. (and can be easily increased in editing)
  - LocalH 5y ago
    > Any brain filtering would have to affect the photos as well, even if it was true. Not when the dynamic range of reality is much greater than that of photographs, and your visual system is one of the best visual processors in existence. It’s like reducing a 24-bit image to 16-bit - the image is “good enough” to identify the subject, but it is quite lossy. Photography itself is a lossy process.
  - dagmx 5y ago
    What is "brain filtering" and why would you think either film or digital can reproduce the same visual effect as our eyes see? Our brain does a perceptual aggregation of multiple frames and inputs. This is not how cameras work. Also "make cameras take physically correct colors" is impossible unless you're talking about spectral capture, which is orders if magnitudes more complex. If you're using just RGB photosites AND RGB displays, there is no such thing as physically correct colors. Everything will just be a mapping at best, with the best that color science experts can actually provide.
    - ElephantsMyAnus 5y ago
      The one I was replying to talked about brain processing. Whatever it is doesn't need to and shouldn't be reproduced in photography as the protograph gets processed just like everything else when you look at it. Reality --> eye --> "brain filter" Reality --> photo --> eye -> "brain filter" Cameras should only record the colors as accurately as possible. Or if you want to nitpick again, so that the photo stimulates the eye receptors identically to whatever was captured.
      - deleted 5y ago
        [deleted]
      - dagmx 5y ago
        they already do that to the best of our abilities. Color is incredibly complex. It's easy to say "we should capture it as accurately as possible" but I don't think you fully comprehend the high complexity involved. Your concept of matching eye receptors is wrong too. Color is perceptual and subjective. Your perception of color is based on your upbringing, your genetics, your environment, your own mental faculties, your mental state etc... What is accurate? Your eyes see some spectral energy, your rods and cones convert those to signals, your brain then adds that into an aggregate set of information that it's constantly infilling and, most importantly, guessing about. You can't guarantee that multiple people see color the same. Now even if a camera could hypothetically capture an image accurately to the real world (IMHO only possible with a hypothetical full spectrum sensor), how would you store it? The second you convert it to RGB data it needs a perceptual conversion to the bit depth of the data format. Now even if you have a file format that can efficiently represent this, you'd also need full spectrum displays so that we could beam that exact color to your retinas. Color science is incredibly complex. You're trying to trivialize it into matching your own narrow perception of color.
- tomc1985 5y ago
  There's something off about the brightness sensitivity curves, if I can dial shadow controls way way up and salvage an otherwise botched, underexposed photo, why is it that I have to do so manually? The dynamic range is clearly there. And we're not talking about such ridiculous values that the sensor noise becomes prominent.
  - unfocussed_mike 5y ago
    > why is it that I have to do so manually? You can do that correction in that situation because you've looked at the image, you know what it is meant to be, and you can decide on a set of adjustments that produce something that approximates what you want, perceptually. But without truly extensive scene knowledge, cameras can't do that automatically, and they also can't know what information that is important to the photographer that they'd be affecting if they did. Cameras have to try to ascertain what would be middle grey in a scene and then apply a general purpose tone curve to an image, but they do not know what is in the scene. They can't even know for sure if the photo they are being asked to take is properly exposed by any absolute definition, in fact. [I cut out a lot of this because I don't think it's going to be easy to complete the explanation here]
    - ElephantsMyAnus 5y ago
      No, the problem is VERY OBVIOUSLY more severe than that. It's really as if the images were treated as linear, which they are not. (they use gamma correction)
      - unfocussed_mike 5y ago
        Honestly, whatever your understanding is here, you should probably build a demonstration to get it across to people. Have you ever shot photographs with a colour transparency film?
      - dagmx 5y ago
        This is also incorrect and trivializing of the color science. Images may use gamma correction, they may not. Trying to describe it in terms of gamma is like trying to describe food in terms of saltiness alone. You're ignoring tons of other factors.
Ma8ee 5y ago
That is exactly what is happening when you lack dynamic range. Say that your eye is sensitive from light intensity 0 to 100 in some units, but your camera sensor only handles 40 to 60. That means that everything under 40 will be mapped to black, and everything above 60 will be mapped to white.
- deleted 5y ago
  [deleted]
- ElephantsMyAnus 5y ago
  No, that does not make any sense. That should result in 40, and everything darker resulting in 40, while 60 and everything brighter resulting in 60. But what you can see is that 40 results in 0, and 60 resulting in 100. That should never happen unless there is an error in processing. Only the picture file format should limit what range you can save with any modern camera.
  - wizzwizz4 5y ago
    It does make sense. 40 is black, and 60 is white.
    - ElephantsMyAnus 5y ago
      No it doesn't make sense. You should not be able to capture anything darker than 40, or brighter than 60 if you are limited to 40-60. (actually by the file format, not the sensor, sensors today have higher dynamic ranges than 8 bit sRGB) It should not turn 40 into 0 and 60 into 100.
      - ubercow13 5y ago
        It's trivial to take an image editor and any existing image that is as you describe, and adjust the black point to 40 "percent" and white to 60%. It won't look more correct or realistic at all.
      - wizzwizz4 5y ago
user-the-name 5y ago
Derbasti 5y ago
It's not the the camera that lacks dynamic range. It's your screen. There's a fundamental problem with photography: a scene can contain up to 20 EV of dynamic range. Your camera can capture up to 14 EV. But your screen or a print can only depict 5-10 EV. So something has to give. The camera capture is usually fine, only excluding the brightest highlights like the sun itself, and the darkest shadows, both of which we don't expect to contain detail anyway. But mapping the rest into the (let's say) 8 EV of available dynamic range of the screen is a problem. Film does it in two ways: it rolls of highlights and shadows smoothly, preserving mid-tone contrast while compressing (and desaturating) extreme tones. Secondly, chemical diffusion enhances local contrast, while reducing global contrast, a bit like the "clarity" slider in Lightroom. Smart phone cameras do something similar, with HDR image fusion, local contrast, and tone mapping. Which is why, ultimately, only an edited picture can represent the experience of viewing a natural scene. The full tonal range of the scene can not be displayed. We have to rely on a somewhat artificial compressed rendition instead. But that's not a fault of the camera, or even the screen. But simply the result of showing an emissive reality on an (assumed) reflective medium. To me, it's the same perceptual unreality as projecting a 3D scene onto a 2D medium. To me, it's what makes photography (and visual arts in general) interesting. They don't show reality, but a depiction of reality. And in that crop, project, compress, lies interpretation and expression.
- ElephantsMyAnus 5y ago
  No that can't be what's happening. You would expect contrast to be lost, not increased, if that was the issue. 8bit sRGB can contain 11.6 f-stops of dynamic range, and it is no longer enough for modern screens. There must be a longstanding bug somewhere. It would not be the first time it happened. There was a chroma decoding bug in almost all DVD players. A very similar issue to this, antialiasing in CGI used to be calculated without gamma, until GPUs got fast enough to use it and I suppose that someone started looking into why it performs worse than expected.

marban 5y ago

The error is the photographer. People just got used to ultra-correction of modern-day phone cams.

unfocussed_mike 5y ago

How is it not from a lack of dynamic range? Colour transparency film (e.g. Fuji Velvia -- RVP50) shows the same thing as clearly. You basically can't map real world light into the dynamic range of a typical camera without causing some of this experience, can you? The question is how you determine how dark shadows should be -- your brain is doing a lot of work to hide from you the tricks it uses to make shadows appear less dark than they might be with a linear response. Or even how they would look with a non-linear response that is even across the "frame"; your brain is doing localised dodge/burn type work, constantly. Camera manufacturers have "tastemakers" for this stuff on digital, just as film manufacturers used to have them for film.

ElephantsMyAnus 5y ago
It is different because it is obvious that shadows are darker than in reality while highlights are much brighter than in reality. Any brain filtering would have to affect the photos as well, even if it was true. No common image format uses linear response. It would explain this problem if cameras treat them as linear. Maybe they should just make the cameras take physically correct colors, instead of relying on people, as the typical person will always choose extreme contrast that will make the camera unusable. (and can be easily increased in editing)
- LocalH 5y ago
  > Any brain filtering would have to affect the photos as well, even if it was true. Not when the dynamic range of reality is much greater than that of photographs, and your visual system is one of the best visual processors in existence. It’s like reducing a 24-bit image to 16-bit - the image is “good enough” to identify the subject, but it is quite lossy. Photography itself is a lossy process.
- dagmx 5y ago
  What is "brain filtering" and why would you think either film or digital can reproduce the same visual effect as our eyes see? Our brain does a perceptual aggregation of multiple frames and inputs. This is not how cameras work. Also "make cameras take physically correct colors" is impossible unless you're talking about spectral capture, which is orders if magnitudes more complex. If you're using just RGB photosites AND RGB displays, there is no such thing as physically correct colors. Everything will just be a mapping at best, with the best that color science experts can actually provide.
  - ElephantsMyAnus 5y ago
    The one I was replying to talked about brain processing. Whatever it is doesn't need to and shouldn't be reproduced in photography as the protograph gets processed just like everything else when you look at it. Reality --> eye --> "brain filter" Reality --> photo --> eye -> "brain filter" Cameras should only record the colors as accurately as possible. Or if you want to nitpick again, so that the photo stimulates the eye receptors identically to whatever was captured.
    - deleted 5y ago
      [deleted]
    - dagmx 5y ago
      they already do that to the best of our abilities. Color is incredibly complex. It's easy to say "we should capture it as accurately as possible" but I don't think you fully comprehend the high complexity involved. Your concept of matching eye receptors is wrong too. Color is perceptual and subjective. Your perception of color is based on your upbringing, your genetics, your environment, your own mental faculties, your mental state etc... What is accurate? Your eyes see some spectral energy, your rods and cones convert those to signals, your brain then adds that into an aggregate set of information that it's constantly infilling and, most importantly, guessing about. You can't guarantee that multiple people see color the same. Now even if a camera could hypothetically capture an image accurately to the real world (IMHO only possible with a hypothetical full spectrum sensor), how would you store it? The second you convert it to RGB data it needs a perceptual conversion to the bit depth of the data format. Now even if you have a file format that can efficiently represent this, you'd also need full spectrum displays so that we could beam that exact color to your retinas. Color science is incredibly complex. You're trying to trivialize it into matching your own narrow perception of color.
tomc1985 5y ago
There's something off about the brightness sensitivity curves, if I can dial shadow controls way way up and salvage an otherwise botched, underexposed photo, why is it that I have to do so manually? The dynamic range is clearly there. And we're not talking about such ridiculous values that the sensor noise becomes prominent.
- unfocussed_mike 5y ago
  > why is it that I have to do so manually? You can do that correction in that situation because you've looked at the image, you know what it is meant to be, and you can decide on a set of adjustments that produce something that approximates what you want, perceptually. But without truly extensive scene knowledge, cameras can't do that automatically, and they also can't know what information that is important to the photographer that they'd be affecting if they did. Cameras have to try to ascertain what would be middle grey in a scene and then apply a general purpose tone curve to an image, but they do not know what is in the scene. They can't even know for sure if the photo they are being asked to take is properly exposed by any absolute definition, in fact. [I cut out a lot of this because I don't think it's going to be easy to complete the explanation here]
  - ElephantsMyAnus 5y ago
    No, the problem is VERY OBVIOUSLY more severe than that. It's really as if the images were treated as linear, which they are not. (they use gamma correction)
    - unfocussed_mike 5y ago
      Honestly, whatever your understanding is here, you should probably build a demonstration to get it across to people. Have you ever shot photographs with a colour transparency film?
    - dagmx 5y ago
      This is also incorrect and trivializing of the color science. Images may use gamma correction, they may not. Trying to describe it in terms of gamma is like trying to describe food in terms of saltiness alone. You're ignoring tons of other factors.

Ma8ee 5y ago

That is exactly what is happening when you lack dynamic range. Say that your eye is sensitive from light intensity 0 to 100 in some units, but your camera sensor only handles 40 to 60. That means that everything under 40 will be mapped to black, and everything above 60 will be mapped to white.

deleted 5y ago
[deleted]
ElephantsMyAnus 5y ago
No, that does not make any sense. That should result in 40, and everything darker resulting in 40, while 60 and everything brighter resulting in 60. But what you can see is that 40 results in 0, and 60 resulting in 100. That should never happen unless there is an error in processing. Only the picture file format should limit what range you can save with any modern camera.
- wizzwizz4 5y ago
  It does make sense. 40 is black, and 60 is white.
  - ElephantsMyAnus 5y ago
    No it doesn't make sense. You should not be able to capture anything darker than 40, or brighter than 60 if you are limited to 40-60. (actually by the file format, not the sensor, sensors today have higher dynamic ranges than 8 bit sRGB) It should not turn 40 into 0 and 60 into 100.
    - ubercow13 5y ago
      It's trivial to take an image editor and any existing image that is as you describe, and adjust the black point to 40 "percent" and white to 60%. It won't look more correct or realistic at all.
    - wizzwizz4 5y ago

user-the-name 5y ago

Derbasti 5y ago

It's not the the camera that lacks dynamic range. It's your screen. There's a fundamental problem with photography: a scene can contain up to 20 EV of dynamic range. Your camera can capture up to 14 EV. But your screen or a print can only depict 5-10 EV. So something has to give. The camera capture is usually fine, only excluding the brightest highlights like the sun itself, and the darkest shadows, both of which we don't expect to contain detail anyway. But mapping the rest into the (let's say) 8 EV of available dynamic range of the screen is a problem. Film does it in two ways: it rolls of highlights and shadows smoothly, preserving mid-tone contrast while compressing (and desaturating) extreme tones. Secondly, chemical diffusion enhances local contrast, while reducing global contrast, a bit like the "clarity" slider in Lightroom. Smart phone cameras do something similar, with HDR image fusion, local contrast, and tone mapping. Which is why, ultimately, only an edited picture can represent the experience of viewing a natural scene. The full tonal range of the scene can not be displayed. We have to rely on a somewhat artificial compressed rendition instead. But that's not a fault of the camera, or even the screen. But simply the result of showing an emissive reality on an (assumed) reflective medium. To me, it's the same perceptual unreality as projecting a 3D scene onto a 2D medium. To me, it's what makes photography (and visual arts in general) interesting. They don't show reality, but a depiction of reality. And in that crop, project, compress, lies interpretation and expression.

ElephantsMyAnus 5y ago
No that can't be what's happening. You would expect contrast to be lost, not increased, if that was the issue. 8bit sRGB can contain 11.6 f-stops of dynamic range, and it is no longer enough for modern screens. There must be a longstanding bug somewhere. It would not be the first time it happened. There was a chroma decoding bug in almost all DVD players. A very similar issue to this, antialiasing in CGI used to be calculated without gamma, until GPUs got fast enough to use it and I suppose that someone started looking into why it performs worse than expected.