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Thread: Effect of diffraction on A7R II sensor

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    Question Effect of diffraction on A7R II sensor

    Sony cook the RAW files to minimize diffraction effects (as they said during A7r's launch) that will dominate when non system lenses are used.

    Does this (RAW cooking) extend to Canon EOS lenses adapted via a "smart" adapter?

    TIA!

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    Senior Member ErikKaffehr's Avatar
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    Re: Effect of diffraction on A7R II sensor

    Hi,

    That is pure nonsense. The way Sony minimizes diffraction effects is by increased sharpening, hopefully just on JPEGs.

    Please realise that diffraction is simply a property of light. Nothing sensor, lens or camera makers can do about.

    But, having more pixels is useful in sharpening. Within some limits, the loss of sharpness due to diffraction can be compensated by sharpening, and that sharpening may work better with smaller pixels.

    Best regards
    Erik

    PS. You can view the problem in the frequency domain. You essentially multiply the MTF of all parts of the processing pipeline. A higher resolution sensor will have a better MTF than a lower resolution sensor, so it will transfer more fine detail contrast.


    Quote Originally Posted by Vivek View Post
    Sony cook the RAW files to minimize diffraction effects (as they said during A7r's launch) that will dominate when non system lenses are used.

    Does this (RAW cooking) extend to Canon EOS lenses adapted via a "smart" adapter?

    TIA!

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    Re: Effect of diffraction on A7R II sensor

    Erik, what is pure nonsense? They even showed a graphic when they launched the a7r to illustrate it.

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    Senior Member ErikKaffehr's Avatar
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    Re: Effect of diffraction on A7R II sensor

    Hi,

    Diffraction is only function of aperture. It's cause is the light bending around the aperture.

    The only thing Sony or anyone else on the planet can do about it is add sharpening. Stopping down the diffraction spot/disc increases in diameter so sharpening needs to be made with a larger radius.

    Deconvolution sharpening can compensate a bit for diffraction, but it is probably best made in postprocessing. Could of course be that Sony applies some superior sharpening method, like Richardson-Lucy, but there is always a risk of ringing artefacts with deconvolution so it is best to do it in post processing.

    Best regards
    Erik

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    Re: Effect of diffraction on A7R II sensor

    That is all fine. But, you do not seem to have read my query. Sony already does it to their RAW files when a system lens is used (you dismiss what Sony have said!). My question was, does that carry to the adapted Canon lenses.

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    Re: Effect of diffraction on A7R II sensor

    Is this the same as the A7r?
    http://discover.store.sony.com/sony-...h_imaging.html
    http://www.dpreview.com/forums/threa...-post-53992997
    http://www.getdpi.com/forum/sony/494...ction-a7r.html

    It's not clear that it's raw or jpg. Do you have an up to date reference Vivek?

    Thx

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    Administrator, Instructor Guy Mancuso's Avatar
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    Re: Effect of diffraction on A7R II sensor

    Quote Originally Posted by Vivek View Post
    That is all fine. But, you do not seem to have read my query. Sony already does it to their RAW files when a system lens is used (you dismiss what Sony have said!). My question was, does that carry to the adapted Canon lenses.
    I don't know this answer but logic would tell me if a Exif file is attached than yes it would. That's purely a assumption and if Sony is even doing it in the first place. Again I don't have any answers on that
    Photography is all about experimentation and without it you will never learn art.

    www.guymancusophotography.com
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    Re: Effect of diffraction on A7R II sensor

    I can tell you this. I just tested the two Batis lenses and the Zeiss 35 and around F11 you can see diffraction starting to set in. Every lens or system I have tested this is pretty normal. So my assumption is the raws are not being cooked in this area. Phase, Nikon you name it the lenses start to go around this area .
    Photography is all about experimentation and without it you will never learn art.

    www.guymancusophotography.com
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    Re: Effect of diffraction on A7R II sensor

    Quote Originally Posted by mbroomfield View Post
    Is this the same as the A7r?
    http://discover.store.sony.com/sony-...h_imaging.html
    http://www.dpreview.com/forums/threa...-post-53992997
    http://www.getdpi.com/forum/sony/494...ction-a7r.html

    It's not clear that it's raw or jpg. Do you have an up to date reference Vivek?

    Thx
    Mike, Guy's answers throw some insight as to RAW vs jpg question.

    I have nothing further to add.

    Guy, Thank you!

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