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I wonder, do you look at your photos on a computer afterwards or just your phone? I've found that photos I shoot with my Pixel look amazing on the device, but w

I wonder, do you look at your photos on a computer afterwards or just your phone? I've found that photos I shoot with my Pixel look amazing on the device, but when I take them back to my computer (a retina laptop) the flaws become really noticeable. I'm talking about things like small amounts of motion blur or the focus not being quite perfect, or increased grain from the sensor size and ISO setting, etc., leading to an image that is just not as crisp as what I'd get on a real camera. But the flaws are easy to ignore on a small display and I suspect many people (not necessarily you) find them good enough as a result.

squarefoot 9y ago
"but when I take them back to my computer (a retina laptop) the flaws become really noticeable." This is true for all phones, no matter the cost. They simply can't compete with much cheaper but dedicated cameras for one vital reason: the sensor and lenses sizes plus noise. Phones need to be thin and they can devote only a small part of their area to a sensor plus lens. That lens also must follow a certain width/depth ratio to minimize image distortion, so if it's thin it also must be narrow, followed by a narrow sensor as well. Since a narrow sensor is exposed to less light than a larger one, to obtain the same level it has to be pushed to higher sensitivity to cope with lesser light, hence the higher noise.
- tigershark 9y ago
  No, the size of the sensor has nothing to do with the light exposure. The amount of light captured is determined by the lens aperture and the photosensitive element size. The problem with small sensors is that their pixel density is much higher and this increases the noise. Also to have the same resolution a bigger sensor can use bigger pixel and that increases the amount of light captured by the single element. For example a full frame sensor with 12MP has a better signal to noise ratio than a 48MP one. If you use a sensor that is 4 times smaller then if you want to maintain the same resolution the signal to noise ratio is much smaller, if you want to maintain the same low light performance then your resolution will be 4 times smaller. Just think about a full frame sensor, if you crop the image in the center the final result will be exactly the same as an image captured with a smaller sensor with the same pixel density.
  - TomTomXC 9y ago
    I don't think thats true. You need to calculate equivalent f-stop for smaller sized sensors to compare the captured light. The f stop mentioned on the smartphone relates to the physical focal length while the 35mm-equivalent focal length is adjusted by the crop factor. As a result the sensor actually covers a small part of the area that could theoretically be lit with such a short focal length (light falling in from the side at large angles).
    - tigershark 9y ago
      There is no equivalent f/stop. There is an equivalent focal length but as I explained it has nothing to do with the amount of light captured by the photovoltaic elements. The equivalent focal length is used only to infer the field of view.
      - TomTomXC 9y ago
        Imagine a 14mm 2.8 on full frame - that's a very wide angle. Of course a 14mm 2.8 on a mobile phone size sensor will not be used a wide angle, as the senor will only cover a tiny amount of the arc behind the lens. While the two lenses theoretically "transport" the same amount of light, the sensor of the smart phone only sees a tiny amount of it in the center of the theoretical image circle. In practical terms of course the smaller-sensor lens will already be constructed to only have a very small image circle and therefore let through nowhere near as much light as the lens constructed for a larger sensor. That's why it makes sense to consider equivalent f-stops for calculations of light amount passing to the sensor, it also has its place in calculation of DOF.

squarefoot 9y ago

"but when I take them back to my computer (a retina laptop) the flaws become really noticeable." This is true for all phones, no matter the cost. They simply can't compete with much cheaper but dedicated cameras for one vital reason: the sensor and lenses sizes plus noise. Phones need to be thin and they can devote only a small part of their area to a sensor plus lens. That lens also must follow a certain width/depth ratio to minimize image distortion, so if it's thin it also must be narrow, followed by a narrow sensor as well. Since a narrow sensor is exposed to less light than a larger one, to obtain the same level it has to be pushed to higher sensitivity to cope with lesser light, hence the higher noise.

tigershark 9y ago
No, the size of the sensor has nothing to do with the light exposure. The amount of light captured is determined by the lens aperture and the photosensitive element size. The problem with small sensors is that their pixel density is much higher and this increases the noise. Also to have the same resolution a bigger sensor can use bigger pixel and that increases the amount of light captured by the single element. For example a full frame sensor with 12MP has a better signal to noise ratio than a 48MP one. If you use a sensor that is 4 times smaller then if you want to maintain the same resolution the signal to noise ratio is much smaller, if you want to maintain the same low light performance then your resolution will be 4 times smaller. Just think about a full frame sensor, if you crop the image in the center the final result will be exactly the same as an image captured with a smaller sensor with the same pixel density.
- TomTomXC 9y ago
  I don't think thats true. You need to calculate equivalent f-stop for smaller sized sensors to compare the captured light. The f stop mentioned on the smartphone relates to the physical focal length while the 35mm-equivalent focal length is adjusted by the crop factor. As a result the sensor actually covers a small part of the area that could theoretically be lit with such a short focal length (light falling in from the side at large angles).
  - tigershark 9y ago
    There is no equivalent f/stop. There is an equivalent focal length but as I explained it has nothing to do with the amount of light captured by the photovoltaic elements. The equivalent focal length is used only to infer the field of view.
    - TomTomXC 9y ago
      Imagine a 14mm 2.8 on full frame - that's a very wide angle. Of course a 14mm 2.8 on a mobile phone size sensor will not be used a wide angle, as the senor will only cover a tiny amount of the arc behind the lens. While the two lenses theoretically "transport" the same amount of light, the sensor of the smart phone only sees a tiny amount of it in the center of the theoretical image circle. In practical terms of course the smaller-sensor lens will already be constructed to only have a very small image circle and therefore let through nowhere near as much light as the lens constructed for a larger sensor. That's why it makes sense to consider equivalent f-stops for calculations of light amount passing to the sensor, it also has its place in calculation of DOF.