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18

Raw files don't really store any colors per pixel. They only store a single brightness value per pixel. It is true that with a Bayer mask over each pixel the light is filtered with either a Red, Green, or Blue filter¹ over each pixel well. But there's no hard cutoff where only green light gets through to a green filtered pixel or only red light gets through ...


15

Optically, all this should do is reduce the output power of the flash. The filters on the sensor itself are going to make it so you only get the red green and blue on each pixel. This device would just absorb a bunch of the light that could reach the subject. For example, some of the light to bounce off a red part is going to reach a blue sensor and not ...


12

The Bayer filter passbands are designed to be make the sensor have a reasonable match to the human eye, while not costing too much. They're fairly leaky even in the visible part of their stop band, and pretty much uncontrolled in the IR. To increase their blocking in the IR a more expensive recipe in a thicker layer would be needed. The thicker layer isn't ...


7

They don't. You're interpreting the raw data wrong. According to the PiCamera documentation, the Pi's 10-bit raw data is encoded as 5 bytes in the following manner: The Pi's Bayer array is BGGR. So the first four bytes contain the most significant bits (bits 10–3) of the blue, green1, green2, and red sensels, respectively. The fifth byte of data packs the ...


7

Partly. Some of the steps normally taken during demosaicing, such as setting black point, are performed when files are converted to DNG and can't be reversed later on. Other steps, such as interpolating the monochromatic luminance values of each pixel into RGB values based on the color mask characteristics of a particular sensor, are not. Converting an ...


6

Your idea is very interesting. But there are some very serious problems. Parallax. Because the sensors will be shifted to each other they will "see" different picture. And the process of creating one photo from those 3 will be serious challenge and will need a lot of computing power Space. In mobile phones you do not have much space so adding one more ...


5

Modern smartphone image quality is limited by their tiny sensor size, lens quality and diffraction, not the demosaicing process. Therefore, the idea does not seem to be useful. Note that aforementioned P20 features a monochrome camera, introducing the same kind of problems with image registration as the hypothetical separate R, G and B cameras (parallax, ...


5

Many video cameras already do just what you propose. But they use a beam splitting system between the lens and the sensors which essentially cuts the amount of light reaching each sensor by roughly the same proportion as using a Bayer masked filter does. The biggest problem with doing it with three different lenses while maintaining a very high degree of ...


5

I see an equal number of red, green, and blue dots - meaning if you looked at this from sufficient distance, just like looking at TV pixels, this umbrella is really GRAY. Any reflected light from it is also going to be essentially gray unless it's focused as it is in the picture. Meaning the reflection from this will be white light with an equal amount of ...


4

Ken is right in the claim you quote — sort of. It is correct that digital cameras today (with the exception of those with Sigma's Foveon sensors) work by using a Bayer matrix, and sensor resolution is quoted as the size of the matrix. Your example image represents a "36 pixel" sensor. However, it's important to recognize that cameras turn this into a full ...


4

thus there must be a certain specific peak wavelength for all the three Not it must not. 1) The spectral sensitivities may have two or more extremums with IR filter removed. 2) Colorimetry does not require the cameras to have the peak sensitivities at specific wavelengths. The extreme example of it is LMS colour space which simulates the human cone ...


4

Due to overlap between the responses of the Bayer filter dyes it's closer to 50% light loss (one stop) than two thirds. Your scheme would work but at the expense of colour accuracy and colour resolution (the demosaicing process would be less constrained and more error prone). Combined with the fact the sensitivity gain is rather modest (up to 25% depending ...


4

Basically, a RAW file stores data directly from the sensor of your camera. Most DSLR are using what is called a Bayer filter (https://en.wikipedia.org/wiki/Bayer_filter) to retrieve information about color. Usually, for 4 "pixels" (sensitive elements), 2 are used to get information about green, 1 for red and 1 for blue. However, keep in mind that this sensor ...


3

Your premise is wrong and lies already in the definition of noise. if it would affect all sensor sites equally, it wouldn't be noise but only an offset. Noise means that some more-or-less random value is added to the signal, different for each sensor site. That's what makes it so hard to remove. see What is noise in a digital photograph? for an explanation ...


3

This technology exists in the form of a 3ccd / 3-chip camera. There would be some issues with fitting the prism into the space available in a phone. I think you would end up with something at least as thick as a gen1 iPhone but something closer to the thickness of a deck of cards might be needed. I suppose the market might be strong enough to support such a ...


3

From the abstract of this article Color filter array for CCD and CMOS image sensors using a chemically amplified thermally cured pre-dyed positive-tone photoresist for 365-nm lithography Diazonaphthoquinone-novolak photoresist is used to produce these filters by successively depositing and patterning each color layer. My understanding of this quote is ...


2

pixel has different meaning in spheres of display technology and sensor technology. pixel of RGB Bayer sensor is represented by only one number (roughly one colour) while pixel of most of RGB graphic displays is represented by three numbers. The number of pixels noted on cameras is not the number of dots divided by four - it is actual number of dots on the ...


2

Only if you still have the original data from the raw file. You cannot normally derive the original monochromatic luminance values from each sensel (pixel well) on the sensor from the demosaiced data because there are almost always more than one set of original data that could result in the same final RGB values, just as there are more than one set of RGB ...


2

It is all true, but the interpretation can be stretched. That specific raw color pattern is called a Bayer pattern. Yes, raw is one color per pixel, and that one pixel is (typically) 12 bits. So there are three colors of raw pixels, some are blue, some are red, and 2x those counts are green. Then later, the raw processing software (to make RGB JPG, it ...


2

There are various alternative colour systems that have been tried in the past but ultimately it comes back to Bayer being 'good enough' and other technologies not panning out. The 'dual pixel' design from the early Fuji DSLRs springs immediately to mind as being a great idea which ultimately didn't deliver enough benefit (although the dynamic range was ...


2

I saw multiple posts online which said it's reduced by 1 / sqrt(2), but they offered no explanation of why this is the case. This one is easy to explain. The typical Bayer tile has two identical green-filtered photosites and one instance of each of red- and blue-filtered photosites. The green-filtered ones are usually on the diagonal. Suppose the ...


2

I figure that at some point someone has devised a demosaic algorithm that is optimal for converting a Bayer DNG to a B&W photograph. Well "optimal" is in the eye of the beholder. Your idea of an optimal conversion may not be my idea of an optimal conversion. So on this notion the idea of an optimal conversion flounders. On a fundamental level, ...


2

Given that sensor noise affects all sensor sites equally/randomly, why does the raw unprocessed Bayer data have such prominent vertical stripes? As @scottbb already explained the RAW format layout and why this creates the striped (in the chat session), you should know now that these are just low level "noisy bits" from four sensor sites (BGGR) combined into ...


1

IF the filters in Bayer masks created three discrete color ranges in which any particular wavelength could only pass through a single filter, then the resolution would be 1/2 for the "green" filtered wavelengths and 1/4 for the "blue" and "red" filtered wavelengths. IF the filters in Bayer masks created three discrete color ranges in which any particular ...


1

Commonly cameras capture data using the full sensor which gives full-resolution RAW data which is converted into an image and then downscaled. As a matter, if you select to shoot JPEG+RAW, you do still get a full-resolution RAW file and a scaled down JPEG. Your proposed using every 4th pixel or average of neighboring pixels is unlikely since it does not ...


1

When talking about blending the layers, creating 3 layers with red/green/blue data and choosing a blend mode of Difference can achieve what you want.


1

If you want to do "astro-photography" , spend your money on the telescope and tracking gear. The camera is almost incidental by comparison. While a grayscale CCTV camera may be cheap, it'll also have crappy resolution and lousy signal/noise ratio. Even with the loss due to the color filter, almost any consumer digital camera will be better. it'll be ...


1

The type of mosaic which tyou are talking about is RGBW. Telling about why it is not used is complex and I may misinform you. I may point at least one thing which in my opinion is most important. So, my question is, what is the main reason we don't see products containing the alternative color filter described above? Every channel of output image is ...


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