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  1. #1
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    Howcome we arent seeing more CMYK sensors?

    Especially on the higher end cameras, i would of expected this to be alot more common since CMYK is more standard in industrial printers ?

    Screw the 4k iso100 f10 nighttime shots, wouldn't CMYK sensors enable us to capture more colors and gradiants ?

  2. #2
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    Can you explain your question, I'm confused I just found only one definition for the term 'CMYK sensor'.

    The CMYK sensor is able to recognize whether an object was printed with three or four colors. CMYK stands for the colors of cyan, magenta, yellow and black, which are commonly used in color printing. Three-color printing manages without black.

    Are there any cameras with special sensors what record the pictures in CMYK colors instead of RGB? If there are then I would be glad for a link for more info. Never heard before.

  3. #3
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    I thought CMYK was just for print, and RGB was for light. This is the case since you can't mix any combo of R G or B inks to get black. You can, however use CMYK inks on white paper to get almost any color.

    On another note, in optics, black is the absence of light. A typical color CCD measures the amount of light hitting it and what wavelength it is. What type of sensor would measure CM and Y, and also Black?
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  4. #4
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    Quote Originally Posted by Csae View Post
    Especially on the higher end cameras, I would have expected this to be a lot more common.....
    I'm confused too!

    Are you talking about printers, which use CMYK, rather than digital camera sensors which utilise RGB? Also, as you say 'a lot more common' this implies that some digital cameras do in fact utilise a CMYK sensor. If so, could you please supply a link?

    Thanks

  5. #5
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    Its a bit tricky to explain, but there is no reason other then price and complexity that a CMY sensor could not be made.

    RGB is easier and has been around more often, but most printers (especially higher up) are CMYK due to the range of tints allowed, i dont know about you guys but i take photos to print them.

    I've been trying to found out more stuff about RGB/CMYK but so far i've only gathered two things :

    1) RGB Can get more deep colors at its extremes, (reds,greens,blues) but is limited to three values, 255,255,255

    2) CMYK Has alot more tints and gradiants but has problems creating deep reds,greens or blues.

    Here is a basic example of what i mean :

    Im not sure how accurate this graph is, but its about the gist of it. What the graph doesn't show is that the gradiants are alot more varied in cmyk then in rgb.


    Unless i misunderstood something, RGB sensors, just measure the amount of red, green,blue that hit by the different wavelenghts, im sure a cmy sensor would be made much in the same manner.

    This might not be ideal for consumer point&shoots because things will look different and not oversaturated, however for any professional this would integrate perfectly into a cmyk workflow. After some googling i had found a couple cameras which use CMY or CMYK rather then RGB, but i can't find the page anymore, i think there were some Kodaks.

    I think the main problem is not recording the image in CMY, but rather displaying it, as pretty much all displays (monitors,tvs,etc) were normalized with RGB.
    Last edited by Csae; 03-13-2009 at 05:05 PM.

  6. #6
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    Quote Originally Posted by Csae View Post
    i dont know about you guys but i take photos to print them.
    I take pictures to sell 'em.
    Ouch.

  7. #7
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    sellout.


    +10characters for minimum posting lenght.

  8. #8
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    For the record, the ccd only measures light intensity. The color information is obtained by putting filters, (usually R,G, and B) in front of the ccd pixels.

  9. #9
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    I'd recommend some additional reading to understand the color reproduction process.
    http://en.wikipedia.org/wiki/Color_printing (overview)
    http://en.wikipedia.org/wiki/Subtractive_color (cmyk explained)
    http://en.wikipedia.org/wiki/Additive_color (rgb explained)
    (many thanks, wikipedia )

    As far as I can conclude, it seams that all of the sensors can be only of the type RGB. Because the sensors are measuring the light emitted from the subjects. It would be possible to include additional processing in the image sensor to convert the captured RGB picture into CMYK coded picture, but it's still post processing as the picture can be captured in RGB only. CMYK is applicable for printed colors only.

    Cheers,
    Last edited by Margus; 03-14-2009 at 03:18 AM.

  10. #10
    Join Date
    Oct 2006
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    There are some things that could be done along these lines. Kodak announced a sensor design a while ago which has grayscale pixels next to the RGB ones sort of like the K in CMYK, or like the design of the human eye.

    One could also make photosites tuned to purple or different shades of green, to help the sensor be more accurate at picking up the subtle differences in those colors. See http://en.wikipedia.org/wiki/Tetrachromacy for examples of this in nature. Of course, it doesn't make much sense to capture colors outside what humans can distinguish, but the idea is that the current technology isn't great at even matching that, so rather than trying to get the individual RGB photosites to be perfect, instead make a wider range and do it in software.
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