Re: Possible to extract high resolution b/w from a raw file?

Discussion in 'Digital Photography' started by David Dyer-Bennet, May 10, 2011.

  1. On Tuesday, May 10, 2011 12:09:54 PM UTC-5, Alfred Molon wrote:
    > In article <99047cc0-d69d-4af4-82bc-18a0fa6bd2e5
    > @glegroupsg2000goo.googlegroups.com>, David Dyer-Bennet says...
    > > I might want a weaker AA filter; not so much because the B&W resolution is
    > > higher, but just because the normal AA is strong enough for the hard
    > > cases, and I'm willing to do post-processing for the hard cases.

    >
    > Postprocessing can't remove aliasing. All you can achieve is making the
    > image look less bad.


    It can't magically recognize and remove aliasing, no. But the practical
    aliasing cases the one runs into can be made to look fine in post-processing.
    And they're rare.
     
    David Dyer-Bennet, May 10, 2011
    #1
    1. Advertising

  2. David Dyer-Bennet

    Bruce Guest

    On Tue, 10 May 2011 10:22:06 -0700 (PDT), David Dyer-Bennet
    <> wrote:
    >On Tuesday, May 10, 2011 12:09:54 PM UTC-5, Alfred Molon wrote:
    >> In article <99047cc0-d69d-4af4-82bc-18a0fa6bd2e5
    >> @glegroupsg2000goo.googlegroups.com>, David Dyer-Bennet says...
    >> > I might want a weaker AA filter; not so much because the B&W resolution is
    >> > higher, but just because the normal AA is strong enough for the hard
    >> > cases, and I'm willing to do post-processing for the hard cases.

    >>
    >> Postprocessing can't remove aliasing. All you can achieve is making the
    >> image look less bad.

    >
    >It can't magically recognize and remove aliasing, no. But the practical
    >aliasing cases the one runs into can be made to look fine in post-processing.
    >And they're rare.



    In another post to this thread I have mentioned that "moire problems"
    with no AA filter are greatly overstated by armchair experts but not
    perceived by working photographers as such a significant problem.

    Exactly the same is true of aliasing. People seem to spend more time
    discussing it than dealing with it. The result is that most DSLRs are
    fitted with anti-alias filters that they really don't ned.
     
    Bruce, May 10, 2011
    #2
    1. Advertising

  3. David Dyer-Bennet

    nospam Guest

    In article <>, Bruce
    <> wrote:

    > Exactly the same is true of aliasing. People seem to spend more time
    > discussing it than dealing with it. The result is that most DSLRs are
    > fitted with anti-alias filters that they really don't ned.


    they definitely need them or they wouldn't be there. do you think the
    manufacturers put them in just for the hell of it? they aren't all that
    cheap.
     
    nospam, May 11, 2011
    #3
  4. David Dyer-Bennet

    nospam Guest

    In article <>, Mxsmanic
    <> wrote:

    > > they definitely need them or they wouldn't be there. do you think the
    > > manufacturers put them in just for the hell of it?

    >
    > Sure, if that sells more cameras. Manufacturers still put in digital zooms,
    > even though they are useless, because it sells more cameras.


    digital zoom costs $0. the code was written long ago, and even if it
    wasn't, it's very, very easy to do. write it once and crank out the
    roms.

    an anti-alias filter is a physical part that costs real money,
    especially in medium format cameras.
     
    nospam, May 12, 2011
    #4
  5. David Dyer-Bennet

    Bruce Guest

    Mxsmanic <> wrote:
    >Bruce writes:
    >> In another post to this thread I have mentioned that "moire problems"
    >> with no AA filter are greatly overstated by armchair experts but not
    >> perceived by working photographers as such a significant problem.
    >>
    >> Exactly the same is true of aliasing. People seem to spend more time
    >> discussing it than dealing with it. The result is that most DSLRs are
    >> fitted with anti-alias filters that they really don't ned.

    >
    >It's the difference between gearheads and those who are actually interested in
    >taking pictures.



    Precisely. ;-)
     
    Bruce, May 12, 2011
    #5
  6. David Dyer-Bennet

    TheRealSteve Guest

    On Tue, 10 May 2011 16:12:32 -0700, nospam <>
    wrote:

    >In article <>, Bruce
    ><> wrote:
    >
    >> Exactly the same is true of aliasing. People seem to spend more time
    >> discussing it than dealing with it. The result is that most DSLRs are
    >> fitted with anti-alias filters that they really don't ned.

    >
    >they definitely need them or they wouldn't be there. do you think the
    >manufacturers put them in just for the hell of it? they aren't all that
    >cheap.


    Judge for yourself. Take a look at
    http://www.maxmax.com/nikon_d200hr.htm and tell me whether you want
    the anti-alias filter there for general use and not taking pictures of
    test charts.

    Steve
     
    TheRealSteve, May 17, 2011
    #6
  7. David Dyer-Bennet

    Bruce Guest

    TheRealSteve <> wrote:
    >On Tue, 10 May 2011 16:12:32 -0700, nospam <>
    >wrote:
    >>In article <>, Bruce
    >><> wrote:
    >>
    >>> Exactly the same is true of aliasing. People seem to spend more time
    >>> discussing it than dealing with it. The result is that most DSLRs are
    >>> fitted with anti-alias filters that they really don't ned.

    >>
    >>they definitely need them or they wouldn't be there. do you think the
    >>manufacturers put them in just for the hell of it? they aren't all that
    >>cheap.

    >
    >Judge for yourself. Take a look at
    >http://www.maxmax.com/nikon_d200hr.htm and tell me whether you want
    >the anti-alias filter there for general use and not taking pictures of
    >test charts.



    There are also pages for the Nikon D300HR and D700HR:
    http://www.maxmax.com/nikon_d300HR.htm
    http://www.maxmax.com/nikon_d700HR.htm
     
    Bruce, May 17, 2011
    #7
  8. David Dyer-Bennet

    TheRealSteve Guest

    On Tue, 17 May 2011 11:57:02 +0300, "G Paleologopoulos"
    <> wrote:

    >"Bruce" <> wrote in
    >news:...
    >>
    >> TheRealSteve <> wrote:
    >>>On Tue, 10 May 2011 16:12:32 -0700, nospam <>
    >>>wrote:
    >>>>In article <>, Bruce
    >>>><> wrote:
    >>>>
    >>>>> Exactly the same is true of aliasing. People seem to spend more time
    >>>>> discussing it than dealing with it. The result is that most DSLRs are
    >>>>> fitted with anti-alias filters that they really don't ned.
    >>>>
    >>>>they definitely need them or they wouldn't be there. do you think the
    >>>>manufacturers put them in just for the hell of it? they aren't all that
    >>>>cheap.
    >>>
    >>>Judge for yourself. Take a look at
    >>>http://www.maxmax.com/nikon_d200hr.htm and tell me whether you want
    >>>the anti-alias filter there for general use and not taking pictures of
    >>>test charts.

    >>
    >>
    >> There are also pages for the Nikon D300HR and D700HR:
    >> http://www.maxmax.com/nikon_d300HR.htm
    >> http://www.maxmax.com/nikon_d700HR.htm

    >
    >
    >Damn that's a huge difference!
    >I wonder if they do the D7000.


    http://www.maxmax.com/nikon_d7000.htm

    Steve
     
    TheRealSteve, May 17, 2011
    #8
  9. David Dyer-Bennet

    PeterN Guest

    On 5/17/2011 4:57 AM, G Paleologopoulos wrote:
    > "Bruce" <> wrote in
    > news:...
    >>
    >> TheRealSteve <> wrote:
    >>> On Tue, 10 May 2011 16:12:32 -0700, nospam <>
    >>> wrote:
    >>>> In article <>, Bruce
    >>>> <> wrote:
    >>>>
    >>>>> Exactly the same is true of aliasing. People seem to spend more time
    >>>>> discussing it than dealing with it. The result is that most DSLRs are
    >>>>> fitted with anti-alias filters that they really don't ned.
    >>>>
    >>>> they definitely need them or they wouldn't be there. do you think the
    >>>> manufacturers put them in just for the hell of it? they aren't all that
    >>>> cheap.
    >>>
    >>> Judge for yourself. Take a look at
    >>> http://www.maxmax.com/nikon_d200hr.htm and tell me whether you want
    >>> the anti-alias filter there for general use and not taking pictures of
    >>> test charts.

    >>
    >>
    >> There are also pages for the Nikon D300HR and D700HR:
    >> http://www.maxmax.com/nikon_d300HR.htm
    >> http://www.maxmax.com/nikon_d700HR.htm

    >
    >
    > Damn that's a huge difference!
    > I wonder if they do the D7000.


    I take the results of those tests with a grain of salt. Those tests were
    run by a company that benefits from the positive results of the tests,

    --
    Peter
     
    PeterN, May 17, 2011
    #9
  10. David Dyer-Bennet

    nospam Guest

    In article <>, Mxsmanic
    <> wrote:

    > If you have an AA filter, there's no way to shoot anything without it. But if
    > you don't have an AA filter, and you see artifacts, you can theoretically get
    > rid of them just by knocking the image ever so slightly out of focus, which
    > has the same effect as an AA filter (and that effect is simply to blur the
    > image).


    the problem with that is you don't know if there are artifacts until
    after you take the photo and look at the results (and given your
    dislike of laptops that won't be until you get home, well after it was
    taken), not to mention that a lot of shots are one of a kind where you
    can't re-take them (weddings, news events, wildlife, etc.).
     
    nospam, May 17, 2011
    #10
  11. David Dyer-Bennet

    nospam Guest

    In article <>, Mxsmanic
    <> wrote:


    > > the problem with that is you don't know if there are artifacts until
    > > after you take the photo and look at the results ...

    >
    > You should be able to remove artifacts of high detail in post production.


    additional work that is not necessary with a properly designed system,
    but more importantly, the alias artifacts are not necessarily high
    detail. they can be low frequency beat patterns, which are *impossible*
    to remove without destroying pretty much everything.

    > Anti-aliasing is a matter of reducing detail, so it should still be possible
    > even after the photo has been taken.


    no, the anti-alias filter blocks what the sensor can't accurately
    capture and would alias. unfortunately, there is no perfect anti-alias
    filter so there's a small tradeoff.

    > In contrast, you cannot restore the detail lost due to an AA filter at the
    > time the photo is captured.


    the detail 'lost' is not real detail. it wasn't in the original scene.
    it's false detail.
     
    nospam, May 18, 2011
    #11
  12. David Dyer-Bennet

    TheRealSteve Guest

    On Tue, 17 May 2011 10:01:24 -0400, PeterN
    <> wrote:

    >On 5/17/2011 4:57 AM, G Paleologopoulos wrote:
    >> "Bruce" <> wrote in
    >> news:...
    >>>
    >>> TheRealSteve <> wrote:
    >>>> On Tue, 10 May 2011 16:12:32 -0700, nospam <>
    >>>> wrote:
    >>>>> In article <>, Bruce
    >>>>> <> wrote:
    >>>>>
    >>>>>> Exactly the same is true of aliasing. People seem to spend more time
    >>>>>> discussing it than dealing with it. The result is that most DSLRs are
    >>>>>> fitted with anti-alias filters that they really don't ned.
    >>>>>
    >>>>> they definitely need them or they wouldn't be there. do you think the
    >>>>> manufacturers put them in just for the hell of it? they aren't all that
    >>>>> cheap.
    >>>>
    >>>> Judge for yourself. Take a look at
    >>>> http://www.maxmax.com/nikon_d200hr.htm and tell me whether you want
    >>>> the anti-alias filter there for general use and not taking pictures of
    >>>> test charts.
    >>>
    >>>
    >>> There are also pages for the Nikon D300HR and D700HR:
    >>> http://www.maxmax.com/nikon_d300HR.htm
    >>> http://www.maxmax.com/nikon_d700HR.htm

    >>
    >>
    >> Damn that's a huge difference!
    >> I wonder if they do the D7000.

    >
    >I take the results of those tests with a grain of salt. Those tests were
    >run by a company that benefits from the positive results of the tests,


    Taking the results with a grain of salt is perfectly fine. But I
    would be more likely to discount the results if they disagreed with
    what is expected. They are exactly what is expected. I.e., high
    frequeny patterns appear aliased while most things are noticeably
    sharper. It's easier to see this with pictures than with words. While
    the company does benefit from positive results of the tests, they are
    pretty up-front when it comes to what to expect from their service.

    Also, with regards to post processing removal of the aliased
    artifacts, you can download a canon raw image from the site that has
    the picture of the airconditioner grill that has the moire pattern and
    see if you can easily fix that yourself. See
    http://www.maxmax.com/hot_rod_visible.htm and look at the A/C grill.

    P.S., I have no relationship at all with the site. I'm just a former
    D200 owner who's upset at the generally soft pictures it took. I
    haven't used their service. I just got a D300 instead, which has about
    the same resolution as the D200 if it had the AA filter removed. Of
    course, the D300 could be better but I don't feel like forking over
    $500 for that.

    Steve
     
    TheRealSteve, May 18, 2011
    #12
  13. David Dyer-Bennet

    Bruce Guest

    TheRealSteve <> wrote:
    >
    >Taking the results with a grain of salt is perfectly fine. But I
    >would be more likely to discount the results if they disagreed with
    >what is expected. They are exactly what is expected. I.e., high
    >frequeny patterns appear aliased while most things are noticeably
    >sharper.



    What hits you when you see the before/after comparison shots is the
    sharpness, but what matters far more is the increased ability to
    resolve detail. Fine detail that would be smudged away by the AA
    filter is instead retained.

    You can compensate for the loss of sharpness due to an AA filter by
    using unsharp mask when editing, but you cannot put back detail that
    was smudged away by a too-strong AA filter.


    >It's easier to see this with pictures than with words. While
    >the company does benefit from positive results of the tests, they are
    >pretty up-front when it comes to what to expect from their service.



    This company is certainly up-front. The before/after comparison shots
    would be a perfect way to hold the company to account if their service
    did not work as well as claimed.

    Maybe it isn't surprising that the D200 benefits greatly from removal
    of the AA filter - it was particularly strong. What I do find
    surprising is the significant difference that can be obtained from
    converting Nikon DSLRs made since the D200.

    In particular, the D700 and D7000 are known to have much weaker AA
    filters than the D200, yet there is still a very useful gain in
    performance. I'm thinking about having my D3 treated this way - it
    has the same sensor as the D700.

    Note that the company doesn't offer a service to remove the AA filter
    from the Nikon D3X. This is because the D3X has the weakest AA filter
    of any Nikon DSLR yet offered for sale, which is why its ability to
    record fine detail on its 24 MP sensor completely blows away the Canon
    full frame DSLRs with 21.8 MP sensors, whose unnecessarily strong AA
    filters turn fine detail into mush.

    No doubt the idiots including Wolfgang Weisselberg, Alfred Molon and
    "nospam" will be along in a minute, foaming at the mouth and telling
    us that we cannot possibly take good pictures without an AA filter.

    ;-)
     
    Bruce, May 18, 2011
    #13
  14. David Dyer-Bennet

    PeterN Guest

    On 5/17/2011 10:47 PM, TheRealSteve wrote:
    >
    > On Tue, 17 May 2011 10:01:24 -0400, PeterN
    > <> wrote:
    >
    >> On 5/17/2011 4:57 AM, G Paleologopoulos wrote:
    >>> "Bruce"<> wrote in
    >>> news:...
    >>>>
    >>>> TheRealSteve<> wrote:
    >>>>> On Tue, 10 May 2011 16:12:32 -0700, nospam<>
    >>>>> wrote:
    >>>>>> In article<>, Bruce
    >>>>>> <> wrote:
    >>>>>>
    >>>>>>> Exactly the same is true of aliasing. People seem to spend more time
    >>>>>>> discussing it than dealing with it. The result is that most DSLRs are
    >>>>>>> fitted with anti-alias filters that they really don't ned.
    >>>>>>
    >>>>>> they definitely need them or they wouldn't be there. do you think the
    >>>>>> manufacturers put them in just for the hell of it? they aren't all that
    >>>>>> cheap.
    >>>>>
    >>>>> Judge for yourself. Take a look at
    >>>>> http://www.maxmax.com/nikon_d200hr.htm and tell me whether you want
    >>>>> the anti-alias filter there for general use and not taking pictures of
    >>>>> test charts.
    >>>>
    >>>>
    >>>> There are also pages for the Nikon D300HR and D700HR:
    >>>> http://www.maxmax.com/nikon_d300HR.htm
    >>>> http://www.maxmax.com/nikon_d700HR.htm
    >>>
    >>>
    >>> Damn that's a huge difference!
    >>> I wonder if they do the D7000.

    >>
    >> I take the results of those tests with a grain of salt. Those tests were
    >> run by a company that benefits from the positive results of the tests,

    >
    > Taking the results with a grain of salt is perfectly fine. But I
    > would be more likely to discount the results if they disagreed with
    > what is expected. They are exactly what is expected. I.e., high
    > frequeny patterns appear aliased while most things are noticeably
    > sharper. It's easier to see this with pictures than with words. While
    > the company does benefit from positive results of the tests, they are
    > pretty up-front when it comes to what to expect from their service.
    >
    > Also, with regards to post processing removal of the aliased
    > artifacts, you can download a canon raw image from the site that has
    > the picture of the airconditioner grill that has the moire pattern and
    > see if you can easily fix that yourself. See
    > http://www.maxmax.com/hot_rod_visible.htm and look at the A/C grill.
    >
    > P.S., I have no relationship at all with the site. I'm just a former
    > D200 owner who's upset at the generally soft pictures it took. I
    > haven't used their service. I just got a D300 instead, which has about
    > the same resolution as the D200 if it had the AA filter removed. Of
    > course, the D300 could be better but I don't feel like forking over
    > $500 for that.
    >
    > Steve


    I have both and got the D300 for the same reason and it has lower noise.
    The soft issue is resolved with a modest amount of sharpening. And yes I
    am well aware that it is difficult to put in detail that may not have
    been captured.

    --
    Peter
     
    PeterN, May 18, 2011
    #14
  15. David Dyer-Bennet

    Whisky-dave Guest

    On May 19, 2:19 am, Mxsmanic <> wrote:
    > PeterN writes:
    > > The soft issue is resolved with a modest amount of sharpening. And yes I
    > > am well aware that it is difficult to put in detail that may not have
    > > been captured.

    >
    > It's more than difficult: it's a mathematical impossibility. That's why so
    > much of photography concentrates on trying to capture as much detail as
    > possible at the moment the shot is taken.


    I think that varies with the type of photo you're taking....or perhaps
    the required result.
    I think lots of people do concentrate too much on such things rather
    than looking at the photo.
     
    Whisky-dave, May 19, 2011
    #15
  16. David Dyer-Bennet

    PeterN Guest

    On 5/18/2011 9:19 PM, Mxsmanic wrote:
    > PeterN writes:
    >
    >> The soft issue is resolved with a modest amount of sharpening. And yes I
    >> am well aware that it is difficult to put in detail that may not have
    >> been captured.

    >
    > It's more than difficult: it's a mathematical impossibility. That's why so
    > much of photography concentrates on trying to capture as much detail as
    > possible at the moment the shot is taken.


    A Wacom tablet and pen can do wonders, if you have the skill. (Which I
    do not.)

    --
    Peter
     
    PeterN, May 19, 2011
    #16
  17. David Dyer-Bennet

    PeterN Guest

    On 5/19/2011 8:46 AM, Whisky-dave wrote:
    > On May 19, 2:19 am, Mxsmanic<> wrote:
    >> PeterN writes:
    >>> The soft issue is resolved with a modest amount of sharpening. And yes I
    >>> am well aware that it is difficult to put in detail that may not have
    >>> been captured.

    >>
    >> It's more than difficult: it's a mathematical impossibility. That's why so
    >> much of photography concentrates on trying to capture as much detail as
    >> possible at the moment the shot is taken.

    >
    > I think that varies with the type of photo you're taking....or perhaps
    > the required result.
    > I think lots of people do concentrate too much on such things rather
    > than looking at the photo.


    Absolutely true. Depends on the purpose form making the image. I
    personally shoot for impression, not for cataloging detail.

    --
    Peter
    My concept & style would never be accepted by National Geographic, or by
    any responsible news media.
     
    PeterN, May 19, 2011
    #17
  18. Bruce <> wrote:

    > No doubt the idiots including Wolfgang Weisselberg, Alfred Molon and
    > "nospam" will be along in a minute, foaming at the mouth and telling
    > us that we cannot possibly take good pictures without an AA filter.


    Ad hominem, ad hominem, I have no arguments, I am a Brucer.

    Plonk.

    -Wolfgang
     
    Wolfgang Weisselberg, May 25, 2011
    #18
  19. Mxsmanic <> wrote:
    > nospam writes:


    >> the problem with that is you don't know if there are artifacts until
    >> after you take the photo and look at the results ...


    > You should be able to remove artifacts of high detail in post production.


    Not without removing real detail as well. Detail that would
    have made it past the AA filter. Depending on the circumstances,
    tons lots of detail.

    > Anti-aliasing is a matter of reducing detail, so it should still be possible
    > even after the photo has been taken.


    Yes, blurring it heavily so that apparent low frequency "detail"
    is blurred away is possible. It also tends to completely ruin
    the image.

    > In contrast, you cannot restore the detail lost due to an AA filter at the
    > time the photo is captured.


    If you really *need* more detail, buy a camera with more pixels.

    -Wolfgang
     
    Wolfgang Weisselberg, May 25, 2011
    #19
  20. David Dyer-Bennet

    nospam Guest

    In article <>, Mxsmanic
    <> wrote:

    > > If you really *need* more detail, buy a camera with more pixels.

    >
    > Why? A camera without an AA filter gives more detail at lower cost.


    it gives false detail.

    if you want *real* detail that was in the original subject, the *only*
    solution is more pixels.
     
    nospam, May 26, 2011
    #20
    1. Advertising

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

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. bob
    Replies:
    66
    Views:
    1,747
    J. Clarke
    Jul 3, 2011
  2. David Dyer-Bennet

    Re: Possible to extract high resolution b/w from a raw file?

    David Dyer-Bennet, May 10, 2011, in forum: Digital Photography
    Replies:
    3
    Views:
    261
    Wolfgang Weisselberg
    May 21, 2011
  3. David Dyer-Bennet

    Re: Possible to extract high resolution b/w from a raw file?

    David Dyer-Bennet, May 10, 2011, in forum: Digital Photography
    Replies:
    3
    Views:
    234
    Wolfgang Weisselberg
    May 21, 2011
  4. nospam
    Replies:
    180
    Views:
    2,799
    John Turco
    Jul 15, 2011
  5. Wolfgang Weisselberg

    Re: Possible to extract high resolution b/w from a raw file?

    Wolfgang Weisselberg, May 16, 2011, in forum: Digital Photography
    Replies:
    31
    Views:
    687
    John Turco
    May 27, 2011
Loading...

Share This Page