2 questions regarding Bayer sensors

Discussion in 'Digital Photography' started by Georgette Preddy, Jun 2, 2004.

  1. But even Star Trek came across with production.....
    John McWilliams, Jun 4, 2004
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  2. Georgette Preddy

    Crownfield Guest

    non responsive to the question. stop, reread, re answer.
    check current H1 promotion...
    Crownfield, Jun 4, 2004
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  3. It works purely on an imperfect method of sampling 3 colours secondary
    to filtering via the differing wavelength absorbing properties at
    different depths of silicon.
    No, it senses 3 colours, something vaguely like green, something
    vaguely like red, and something vaguely like blue, however the
    filtering propertises of silicon, and inaccuracies in depth of the
    doping means that each pixel may have slightly different properties,
    as well as cross contamination of colour.

    No matter how much bafflegab you attach to it, the real world shows
    that the Foveon idea, although great in a theoretical sense, is unable
    to perform to the hoped for theoretical ideal. Examining an
    unprocessed RAW image from a Sigma clearly shows that the colours are
    undersaturated and have a gray-green cast. Serious interpolation is
    then required to (hopefully) restore the colours to something that
    they actually looked like.

    grant kinsley, Jun 4, 2004
  4. Actually, only 4 megapixel, since it had only 4 million sensing
    locations in the image plane.

    George has taken to multiplying actual pixel counts by 9 instead of 3
    recently. The first factor of 3 on the (wrong) assumption that
    resolution is increased by measuring multiple colours per pixel, and
    the second factor of 3 presumably because he forgot that he already
    multiplied by 3 a second before.

    Dave Martindale, Jun 4, 2004
  5. Your statement above claims that they sold film, your reading
    comprehension of even your own posts is pathetic.

    grant kinsley, Jun 4, 2004
  6. Georgette Preddy

    Mick Sterbs Guest

    Mick Sterbs, Jun 4, 2004
  7. Georgette Preddy

    Mick Sterbs Guest

    What a bunch of crap. You moron.
    Mick Sterbs, Jun 4, 2004
  8. Georgette Preddy

    Don Stauffer Guest

    I have a feeling we may be arguing about the definition of the word
    color. If we illuminate a scene with a green laser, there would be a
    signal in every pixel. To me it would still be a monochrome image, even
    though (because of finite filter transmitttance) each pixel, even in a
    Bayer array, would have a non-zero signal, and one could derive both a
    luminance and a chrominance value. To me color means light is caused by
    more than one wavelength, and one can distinquish, to some degree
    anyway, wavelengths of light that created color.
    Don Stauffer, Jun 4, 2004
  9. Georgette Preddy

    bagal Guest

    bagal, Jun 4, 2004
  10. Georgette Preddy

    bagal Guest

    Foveon doesn't "perceive" color, it simply registers atomic momentum
    Far be it for me to be biased but I think he may be correct.

    Color is a term to describe the way humans perceive particular waveforms

    As sensors are not human (bear with me I know) they cannot perceive colors.

    Sensors do perceive particular waveforms at particular wavelengths so I
    suppose a 2D sensor arrangement has differences to a 3D sensor arrangement
    (I know - it is obvious)

    Incidentally, there are reports of some individuals that can see wavelengths
    associated with sounds I just thought I'd mention it. It has a technical
    medical term but I can't be assed trying to remember it.

    bagal, Jun 4, 2004
  11. Most of the amateurs I've come in contact with through the years
    couldn't tell a good image from a bad one, and don't really care to
    learn about how to create good ones.

    Anything else you'd like to know?
    Randall Ainsworth, Jun 4, 2004
  12. (Georgette Preddy) wrote in
    Oh .. nice one!

    You have already got the Sci Fi and Star Treck comments, so I will
    spare you any such things ...

    I am trying to make up my mind if you are (1) making fun of us,
    (2) all nuts or (3) has a very strange view on reality. Hmmm ...
    sometimes 2 and 3 are the same.

    Now - color? What is color? How shall you make a device that
    can produce color picturs that look true to reality? There are
    basically two methods: (1) register the spectrum as good as possible
    and then display it and (2) use a small number (usually 3, but you can
    use 2,4,5,6 ...) of bandpass filtered detectors.

    Bayer and Foveon uses the second method. Your reply hints at
    you thinking that Foveon (in some way) use the first or
    something similar. This is wrong.

    Roland Karlsson, Jun 4, 2004
  13. Georgette Preddy

    Bill Funk Guest

    Yet another demonstration of your lack of reading comprehension.
    OR, you're trying real hard to be dishonest.
    If I were you, I'd cop to the former, because it would be simple to
    fix, if you'd apply yourself, but claiming dishonesty is something
    most people don't want to do.
    Bill Funk, Jun 4, 2004
  14. I cant knock the concept... and the implimentation is not bad...
    others that look in more detail may find errors and odities, but as
    and idea I think given the same amount of time in development as the
    "bayer" it may be better, or it may be dropped eventually as a

    It may even be that no matter how good it gets, and even if suppasing
    bayers that it will go the way of betamax... while technically better
    than vhs, just couldnt hack it in the open market place.

    They just need better RnD and marketing, and fewer posters such a GP
    screwing them up :)
    Jonathan Wilson, Jun 5, 2004
  15. I wasn't going to go there.. but then changed my mind, lol

    In a studio portrate style shoot, if you have say 30 photos to choose
    from and decide that 3 are the ones to choose to put infront of the
    amateur or "public" then they will probably say "yes, I like that..."
    (or better) and will hand over the money to buy the print.


    If you show them the full 30, then the odds are that a lot will
    actually choose ones that you felt were not good enough to even

    To partially prove the point.. I took some shots of a person, and
    chose the ones I felt were good focus, composition, angles, lighting,
    the works... moved them to a folder so they could pre-view them.

    They asked me if I could show them the full shoot as they knew I had
    taken more shots during the session... so I did...

    One shot that I had taken that was totally screwed in my opinion, the
    focus was totaly shot and was to dark, was the one they liked the
    best... it was an experiment of a close up of the eye and surounding
    face, from just above the eyebrow to just above the lips and a
    fraction of the nose... when I took it I had set the wrong focus point
    and moved as I took it, it was so bad it should have been binned but I
    keep even my fails so I have a record of where I mucked up.

    She ordered that one, and the ones I'd selected, and then re-ordered
    the mucked up print 8 times for friends and families as they all loved
    the screwed up shot....

    Perhaps there is no acounting for tastes, but the technically perfect
    photo is not always the one that the majority of people prefer given
    the option.

    When I had my old G2 I took a picure of UKBabe that for whatever
    reason the camera decided to muck up the AF and I ended up with a
    blured out of focus shot... on a whim I greyscaled it and fuzed out
    the foregound, the cameras point of focus, more than the subject,
    ended up being quite a good seller!

    I've learnt its not the technical quality of the photo, but more what
    people see in it, and if you can get people from different walks of
    life to read into a photo and see their lifestyle then even better.


    That was a end of session photo, we'd tried a lot of different ideas
    over the preceding 3 hours and UKbabe was shattered as was I... A lot,
    no a big lot, of the shots didnt work as they were pure experiments
    and she was kind enough to go with the flow...

    From the BDSM side... I've had "shes a sub in sub-space"
    Swingers... "shes looks as tho shes really enjoyed herself"
    Others... "thats so cool, it reminds me of how my missus looks when
    we've had fun"
    "It looks like someone asleep as the sun comes up in the morning on a
    summer day"
    "that looks so real and natural"

    and others along the lines of "she's cute" "can i have her number" "I
    would" etc, lol.

    yes there are technical problems with the shot, the colour balance is
    wrong, the bottom mid left is close to over exposure when the top
    right is close to under exposure, where she is curved just above the
    hip she has a "roll" that could have been removed by getting her to
    lift her tummy upwards, she has 2 freckles on her back, and her school
    jab (mmr?, i forget which one they do, lol) on her left arm, nicker
    line on her right butock, and what looks like stretch marks on her
    right hip/thigh due to the tan... so where does one decide "yes" or
    "no" technical details, a "feel" or something that just appeals and
    might be/look natural for all its faults?

    Is putting gausian blur on a photo the same as a soft focus filter, or
    just getting the focus off... all 3 methods can result in the exact
    same looking shot! A "pro" might say.. shit that was out of focus..
    but I like the look of it, its a keeper... where an amateure may go
    wrong is saying "shit, ballsed that up... delete it" its nothing to do
    with apparent standards, its what someone personally likes, and what
    others like... pro or non-pro is down to making money from it in
    technical terms... I've seen ami work that would knock socks of some
    pros, but they do it purely as a hobby for the enjoyment of taking a
    lovely looking "snap."

    Jonathan Wilson, Jun 5, 2004
  16. True, and some people are more receptive to frequency of light than
    others... some get headaches due to the 50Hz cycle of mains in
    lightbulbs, even tho they are like slow phosper in that they retain
    most of the brightness due to the way they work, there is a very
    slight modulation... my mum used to have a problem with them at
    certian positions... the same with computer screens and Tv's. Now that
    they are available she finds the 100Hz tv's and computer monitors at
    high frequencys far more comfortable, and oddly the "power saver"
    bulbs, yet I find the powersaver bulbs to variable in the light output
    over a few months of usage.
    Jonathan Wilson, Jun 5, 2004
  17. In a studio portrate style shoot, if you have say 30 photos to choose
    I can only speak for my own photography as I did it for many years as a

    Regardless of the number taken in a studio sitting, the customer would
    see them all except for the blinks or obviously no-good ones. There
    was very little editing.
    Randall Ainsworth, Jun 5, 2004
  18. Georgette Preddy

    Bryce Guest

    As always, a total loser.
    Bryce, Jun 5, 2004
  19. The SD9 demonstrates at least 3X the resolution of the 1Ds, see the
    test results above. Why such a monumental advantage over a 2.76MP
    DSLR like the 1Ds? Because the 1Ds spreads its relatively small
    number of full color MPs over much more sensor area (but with smaller
    pixel pitch, due to its old 1 layer design). The penalty of more FOV
    is less optical resolution per unit area. If the SD9 snapped the same
    FOV as the Canon by using a wider lens, it would only have (3.43/2.76)
    times the optical resolution per unit area as the 1Ds.
    Georgette Preddy, Jun 5, 2004
  20. Georgette Preddy

    Lionel Guest

    No, I'm afraid not. Like any other tri-colour sensor, (or indeed, the
    eye) the Foveon filters the incoming light into three bands. In fact,
    one of the big drawbacks with the current X3 sensors is that they don't
    do the 'splitting' as accurately as a good prism or dye-filter system.
    Foveon actually acknowledges this, & recommends the use of a separate
    correction filter in front of the sensor to improve the matching of its
    sensitivity to that of the human eye, but Sigma decided not to do this,
    presumably either for cost reason, or to improve light sensitivity. I
    expect that this is the reason for the colour problems in the SD9/10
    that so many people here have commented on.
    Lionel, Jun 5, 2004
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