APS sensors or smaller are the future of the professional market

Discussion in 'Digital Photography' started by deryck lant, Mar 13, 2005.

  1. deryck  lant

    deryck lant Guest

    More and more people are beginning to realize this.

    http://www.luminous-landscape.com/essays/dof-rebuttal.shtml

    http://forums.dpreview.com/forums/read.asp?forum=1021&message=12606303

    The 35mm format was adopted, largely by accident, 80 years ago, for a
    totally different capture medium.

    These are the concluding words in a technical report in this weeks
    The British Journal of Photography. The article analyses all the optical
    aberrations encountered in digital imaging.

    Next week the 16th of March they begin a 2 weeks review of the D2X.

    Deryck
     
    deryck lant, Mar 13, 2005
    #1
    1. Advertisements

  2. deryck  lant

    Alfred Molon Guest

    Interesting - so the 4/3 standard is not such a bad idea after all...
     
    Alfred Molon, Mar 13, 2005
    #2
    1. Advertisements

  3. deryck  lant

    Barry Bean Guest

    Don't tell Steve.
     
    Barry Bean, Mar 13, 2005
    #3
  4. deryck  lant

    Skip M Guest

    And you reached this conclusion how?
     
    Skip M, Mar 13, 2005
    #4
  5. This is true. It was just kind of luck that the resolution and pixel size
    make the 36x24mm frame an almost ideal size for professional cameras. The
    semiconductor physics as they relate to noise, and the current resolutions
    of pro cameras of 8-17 megapixels, make the 36x24 area almost ideal. 30x30
    would be good too, but the legacy lenses are all in the 3:2 format, as
    opposed to the 1:1 or 4:3.

    Now if someone figures out how to do a 12-20 megapixel sensor in the APS
    size sensor, with the same noise level as is currently being obtained with a
    36x24 sensor, then APS might have s a future in the professional market. But
    the Nikon D2x is proof that APS size sensors have a long way to go in terms
    of noise.

    Of course the other issue with APS size sensors is the difficulty and
    expense of producing true wide-angle lenses.

    The optimal size sensor for lenses that were produced for 36x24mm film, is
    probably around 32x21 since this would eliminate the vignetting problem,
    while not reducing the pixel size by much. Alternatively, new lenses for
    36x24 digital could easily eliminate the vignetting issue, but at a higher
    cost.

    The bottom line is that the only reason that Nikon bad-mouths the larger
    sensors is because they don't make them, or have access to them.
     
    Steven M. Scharf, Mar 14, 2005
    #5
  6. Uh, it should be obvious. Olympus uses 4:3.
     
    Steven M. Scharf, Mar 14, 2005
    #6
  7. It's not the idea that's bad, it's the execution. If a sensor manufacturer
    can figure out how to make a low noise sensor in 4:3, and if the camera and
    lens makers come out with a wide variety of 4:3 lenses, then it might work.
    Too bad that no one can figure out how to violate the laws of semiconductor
    physics.
     
    Steven M. Scharf, Mar 14, 2005
    #7

  8. Don't feed the trolls! Notice that his name is very similar to Dreck &
    Slant? Larger sensors on a chip have less noise so the image from a large
    8mp chip will be better than from a small 8mp chip.
     
    Gene Palmiter, Mar 14, 2005
    #8
  9. I would be happier with a 4/3 sized sensor (half 35mm in each dimension,
    yes?) than the smaller sensor on today's P&S, but I have been very
    disappointed with the size, weight and cost of the resulting systems so
    far.

    Cheers,
    David
     
    David J Taylor, Mar 14, 2005
    #9
  10. deryck  lant

    deryck lant Guest

    The message <>
    The lengthy BJP technical report says briefly:

    Digital sensors are very unforgiving when the light strikes them at a glancing
    angle. The problem is most evident with wide angle lenses, from which light
    emerges at a steep angle. This can cause vignetting and colour fringing. The
    solution to these problems is to have a telecentric design lens.

    To accommodate the telecentric lens design the camera lens mount opening
    has to
    be twice the diagonal of the sensor.

    Full frame diagonal of 35mm film/imager is 43.3mm.

    The Nikon lens flange opening is 45mm.
    The Canon lens flange opening is 48mm.
    The Olympus 4/3 system is 46mm (this is why the Olympus is larger than
    you expect)

    A full frame digital camera at 43.3 frame diagonal would require a
    flange opening
    of 87mm, wider than a 6x7 camera.

    APS sized sensors enable the manufacturer to do their best to make the
    newer WA
    lenses as telecentric as possible.

    Deryck
     
    deryck lant, Mar 14, 2005
    #10
  11. Does the report concentrate only on the vignetting issue with wide angle
    lenses (which incidentally is also a problem with film)? There are solutions
    to this problem via new optics. There is no true solution to noise, other
    than larger pixels.

    The flange opening does NOT need to be 2x. A slightly smaller than full
    frame sensor, i.e. what's in the 1D Mark II, combined with new optics, will
    solve this problem.to a large extent. As does cropping with a full frame
    sensor, when uses with wide angle lenses.
     
    Steven M. Scharf, Mar 14, 2005
    #11
  12. deryck  lant

    deryck lant Guest

    The message <fSiZd.3704$>
    Anders Uschold in the previous week's BJP tested the EF 17-40 f/4 L USM,
    the EF 24-70mm f/2.8 L USM, the EF 70-200mm f/2.8 L USM and the EF
    70-200mm f/4 L
    USM. The camera was the EOS 1Ds Mark II.

    The EF 17-40mm. Showed 60 to 100 percent corner light fall off. Also
    resolution was
    restricted and required the lens to be stopped down. Very high
    distortion at 17mm.

    The EF 24-70mm. Showed over 60 to 100 percent corner light fall off.
    Lens should be
    stopped down one or two stops to improve resolution etc. Optical
    distortion is good.

    The EF 70-200mm f2.8. Showed around 60 percent corner light fall off.
    Resolution not
    wonderful. Optical distortion normal to good.

    The EF 70-200 f/4. Showed around 50 percent corner light falloff.
    Resolution is good
    and optical distortion normal. This is the only lens of the four he
    recommended for use
    on the EOS 1Ds Mark II.

    All the lenses were recommended to stopped down one or two stops.

    Regarding noise. Technology is developing fast. Panasonic have announced
    a sensor
    with two micron elements. Panasonic reduced the conductor path wiring
    from 2.5 to 1.5
    microns, providing an extra 40 percent of the chip space for
    light-gathering. Despite
    doubling the number of photo diodes in a given area, noise should not
    increase.
    This sensor, if scaled up to Four Thirds size, would have 36 million pixels.

    Deryck
     
    deryck lant, Mar 14, 2005
    #12
  13. deryck  lant

    eawckyegcy Guest

    deryck lant blithered:
    Physical reality is faster.
    Canon 1DMkII: ~8um pixels.
    Uncited Panasonic sensor: 2um pixels.
    Some arithmetic:

    8*8 = 64
    2*2 = 4

    Now even if Panasonic increases the fill-factor to 100%, which sensor
    is better?
     
    eawckyegcy, Mar 14, 2005
    #13
  14. Actually, the solution is microlenses.
     
    Brian C. Baird, Mar 14, 2005
    #14
  15. If you looked up the meaning of telecentric and understood the definition,
    you'd find yourself to be really embarrassed to have quoted that so
    blithely.

    By the way, wide angle lenses for SLRs are all retrofocus designs, and
    involve ray angles that are much less than those of the 50/1.4 lens.

    The "wide angles don't work on dSLRs" bit is largely FUD.

    David J. Littleboy
    Tokyo, Japan
     
    David J. Littleboy, Mar 14, 2005
    #15
  16. Or you could just use retrofocus lenses, where the light is nowhere near a
    steep angle.

    Oops. I forgot. All the SLR wide angle lenses are retrofocus.

    David J. Littleboy
    Tokyo, Japan
     
    David J. Littleboy, Mar 14, 2005
    #16
  17. deryck  lant

    deryck lant Guest

    deryck lant, Mar 15, 2005
    #17
  18. I bow to your superior knowledge of optics, good sir.
     
    Brian C. Baird, Mar 15, 2005
    #18
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.