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13

An unfiltered CCD or CMOS sensor looks very similar to any other silicon integrated circuit that has a very regular/repeating structure of similar structure size - semi-metallic gray (from silicon, quartz and aluminum) with some iridescence probably resulting from diffraction grating effects in the fine, repeating structures. Compare a bare DRAM or flash ...


12

Note: This is a simplified answer. It does not go into detail, and therefore, please do not take it as authoritative answer on specifics about the exact processes that take place inside a digital camera. The same sensor does not necessarily mean equal pictures. The sensor is one component of the whole process - the others are the analog-to-dicital-...


10

To take a digital picture you need: Optics Sensor Image processing (CPU and algorithms) As you see, sensor is just a one link in a chain, and the chain is as weak as it's weakest link. Currently, we are experiencing great technological progress in the third stage. Compared to DSLRs, smartphones have abysmal both optics and sensors - however the ...


10

Your link discusses how a CCD (charge coupled device) image sensor works. Note, CCDs have applications besides images sensors, but the vast majority of CCDs are used as image sensors, and that is the only primary application I will be discussing. CCDs In typical CCDs used for color image sensing each CCD cell has a color filter over it. The most commonly ...


7

No, you won't obtain the photon count directly. Also, a camera sensor has noise, not just from photon counting but also from electrical circuits. Also, a DSLR has a color filter on top of the pixels, even if you take only grayscale images. It will probabilistically filter away some photons. If the photon is of the correct color, chances of it passing the ...


5

Probably the same image quality, but not necessarily. It's not only the sensor that takes the picture. It's also the lens. The sensor doesn't have an integral lens, it's the camera manufacturer that selects the lens. It is for example possible that the field of view on both cameras is slightly different due to slightly different focal lengths (although ...


5

No, this is not a problem. I see red noise. I see green noise. I see blue noise. That's not a surprise because there are three main colors in the Bayer filter, and the pixels beneath all of those three main colors are noisy. The red and green noise are however more prominent, because the image is blue. This noise is called chroma (chrominance) noise, as ...


5

... why don't we just have big pixels (and thus large sensor surfaces, because we keep the number of pixels fixed)? There are camera models with lower resolution sensors, but the reason they are made is for increased light sensitivity, not DOF. If you want deeper depth of field, consider small sensors, wide-angle lenses, and small apertures. This ...


4

Even the same exact camera will not demonstrate the same "exact" noise characteristics on successive shots. But techniques such as "dark frame subtraction" or other noise reduction processes that measure unexposed areas of the sensor and other characteristics of the noise generated by the camera's circuitry will be "close enough for government work." Image ...


4

"its known that lenses are generally sharpest at the F/8" That is not correct. Some lenses are sharpest at f/8, most reach their max at one to two stops from wide open, and some are sharpest when wide open. You need to test your lens/combination, or find a good test online. Strictly in terms of sharpness, you should use the widest aperture that doesn't ...


4

You cannot calculate sensor size from just focal length and resolution. Since resolution can vary depending on the sensor's construction, this just plain is not enough information. If you have a scientific application, you should buy parts where the specifications are known. If it doesn't matter that much, you can measure the angle of view in practice from ...


4

Get an idea on the spectral sensitivity and quantum efficiency of your camera. The data are provided by the camera manufacturer and/or chip manufacturer. It's easier for monochrome cameras as there is no colour filter (bayer pattern) involved. They are also more light sensitive. CCDs are more sensitive than CMOS and CCD is also more linear. (Your Canon ...


3

I've personally seen sensors of various colors in different cameras; green, pink, blue, etc. Without the specific dimensions and details on construction, it is tough to say, but I'd imagine that the color on most sensors is given by the thickness of the coatings on top of the sensor. Different thicknesses will produce different colors due to thin-film ...


3

I'm sure manufacturers have done internal tests, but I am not aware of any public data. As long as the sensor lasts significantly longer than other components that might fail, any reduction in the life expectancy of the sensor as a result of self cleaning would be inconsequential. For cameras that have been well-cared for (eg, not dropped or dunked in ...


3

To answer your question directly, there isn't a photographic reason why it would be shifted from the optical axis, other than packaging, electronics, weight placement, or other industrial design compromises that are specific to that camera or model line. But to fix the issue so that the optical axis intersects the axis of panoramic rotation, the easiest ...


3

There are no camera settings that will create pixel intensities that correspond linearly to the number of photons. The conversion from raw camera sensor data to an image is non-linear. To get something proportional to photons, you will need to access the raw file directly. This is non-trivial, the file format is complicated, and some of the processing steps ...


2

It might be noted that since this question has been asked, this idea has been somewhat implemented in (at least some) smartphones. As the technological limits did not improved that much, it is of course restricted to very long exposures in very low light (e.g., astrophotography). The fact that the software stacks multiple n-second exposures is visible if ...


2

Personally I don't worry too much about dust unless it is obviously visible in images, which is more likely in photographs of clear skies stopped down completely than in photographs of more complex scenes wide open. If you want a chance at getting your sensor "clean", you need to work in a clean environment. Otherwise, your sensor may still contain numerous ...


2

I suspect small clusters of sensels are dying off. This could happen if the sensor were damaged by lasers. Or perhaps the phone was dropped too many times and some internal connection was damaged. The following image from ILDA: Laser show damage to cameras shows laser damage that has essentially the same appearance as those in your sample image: The black ...


2

It looks like green sensels have gone dark. Lasers can cause damage like this. ILDA: Laser damage to cameras Gizmodo: Laser Light Show Burns a DSLR Sensor


2

The answer is "C", something entirely different. The signal-to-noise ratio used in imaging is the ratio of the mean signal value divided by the standard deviation of the signal. This is used because photon counts, luminous intensity, etc., are always-positive values that are basically probability distributions. Regarding dB (decibel) scale, imaging uses ...


2

Photographic film is naturally sensitive only to violet and blue light frequencies. Hermann Vogel, Professor Berlin Technical, attempting so solve the problem due to “halation”,. He had some emulsions dyed yellow to arrest blue light exposing from the reflections from the emulsion-base interface. The It worked but to his amazement, the film gained ...


2

The pixels you get in a finished, camera-independent image file - a JPEG, TIFF, BMP, ...) file you get either from your camera or from your RAW processor software - are usually the results of multiple photodiode outputs (sensor pixels) combined, due to the way color filters arrays work. The pixels in an image file, or in an image displayed on a monitor, ...


2

Removing glass from the light pathway would result in the loss of infinity focus unless you can decrease the distance between the lens and sensor "past" infinity. Helicoids, bellows, extension tubes will not be helpful because they increase the distance between the sensor and lens. I suppose what you mean by "short build" adapter is that it is shorter than ...


2

Your screenshots show ~300% magnification. For comparison, I have a 24" 1920x1200px (so ~94 ppi) monitor and viewing your picture at 30% zoom (which would roughly be the size at 300dpi), it just fills my monitor from top to bottom! What you are doing is known as pixel-peeping - and 300% is an extreme version of that. While it is not inherently bad to pixel-...


2

If you are asking about sensor (really the filter in front of the sensor) cleaning solutions -- such as "Eclipse" ... that's nearly pure methanol. It is used because it evaporates rapidly and leaves no residue. See: https://photosol.com/products/eclipse-optic-fluid/


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