davide sorasio Posted January 5, 2016 Posted January 5, 2016 Hi everybody, I'm reading David Stump's digital cinematography manual and I need a couple of clarification. Is BAYER FILTER ARRAY (or any other color filter mosaic) used in both RAW or RGB signal output cameras? And does it have something to do with it or that's just a way that the sensor read the lights and it's independent from the file format? It's kind of confusing to me because I wonder if the Bayer CFA is used only when shooting raw or if it's just a system that is independent from the FILE FORMAT. Thanks in advance for the help!
Premium Member Tyler Purcell Posted January 5, 2016 Premium Member Posted January 5, 2016 The Bayer pattern is always there, but it's executed differently with RAW. http://www.adobe.com/digitalimag/pdfs/understanding_digitalrawcapture.pdf
Premium Member Adrian Sierkowski Posted January 5, 2016 Premium Member Posted January 5, 2016 Bayer is a part of, as far as I know, EVERY single chip imager-- e.g. pretty much every camera made these days, stills and video. It's a way to derive 3 colors from a single chip which has essentially monochrome photosites. As such it doesn't matter at all if it's raw or not. My cellphone is a bayer-ed CMOS (though you could have a bayer CCD as well). The only real difference is with Raw, you don't record debayered data-- that is saved for later on, normally done quickly for editorial and then very slowly when you get to your conform stage.
dan kessler Posted January 6, 2016 Posted January 6, 2016 (edited) Don't want to delve too far into something at which I'm no expert,but there is one variant that does not have a Bayer pattern.The foveon chip, which is utilized in Sigma digital cameras, is an RGBdesign whose construction is similar to film itself. It is a layeredarrangement with no offset. It delivers stunning images with absolutelynone of the artifacts associated with the Bayer pattern. I often wonder why it hasn't made a bigger splash. They don't seem to market it very aggressively. Edited January 6, 2016 by dan kessler
Premium Member Tyler Purcell Posted January 6, 2016 Premium Member Posted January 6, 2016 DALSA's imagers didn't have Bayer either.
Premium Member Phil Rhodes Posted January 6, 2016 Premium Member Posted January 6, 2016 I think they did, at least the one in the Origin did. Other things have been tried. The chips used in the F35 (and thus Genesis) had vertical stripes of red, green and blue. There are various workable approaches, with various upsides and downsides. The difference with (various riffs on) raw is that the process of recovering a normal RGB image from the sensor data isn't done in camera, or at least the version that's done in camera is just for viewfinding and isn't final. The problem this creates is that every camera manufacturer likes to claim that their process is clever and special and different to everyone else's, which largely isn't necessary, and it creates a lot of compatibility issues and general headaches in post. P
Kyryll Sobolev Posted January 6, 2016 Posted January 6, 2016 Phil, maybe you can help me understand this better, but from my reading I understood that 2/3 of the colour information is essentially "made up" by the chip (extrapolated if you will) is that wrong way of thinking about it?
Premium Member Phil Rhodes Posted January 6, 2016 Premium Member Posted January 6, 2016 No, that's quite correct. This is why people tend to question whether cameras with 4096-pixel-wide Bayer sensors are really 4K. P
Premium Member Adrian Sierkowski Posted January 6, 2016 Premium Member Posted January 6, 2016 And that's not even getting into anything like the Nyqist limit and the whole notion of MTF--- however that's too deep i find. Effectively, let's say a 4K Bayer resolves about 80% of what it samples and in almost every case, the difference is so academic as to not be an issue in a real world situation.
Premium Member Phil Rhodes Posted January 6, 2016 Premium Member Posted January 6, 2016 about 80% of what it samples On relatively unsaturated subjects, yes. On more saturated subjects, it can be considerably worse, depending what compromises of sensitivity, resolution and aliasing the manufacturer has wrought.
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