Interesting Leica product announcements today ...

Discussion in 'Digital Photography' started by Bruce, May 10, 2012.

  1. Ah yes, the secret unadmitted RAW processing which some camera makers
    are alleged to indulge in. There does seem to be some evidence
    that it happens in at least some models by some manufacturers.
     
    Chris Malcolm, May 17, 2012
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  2. You're stating "facts" tat turn out to be wrong and make
    sense only for an overly simplified model.

    Roger Clark, in
    http://clarkvision.com/articles/digital.photons.and.qe/index.html
    writes:

    | The green filter peak probably has a maximum transmittance of
    | 90% based on my experience with similar filters (this is very
    | optimistic)(see Reference 10).

    [... References ...]
    | 10) http://www.ifa.hawaii.edu/~wang/misc/QE.jpg 4 plots:Canon 20D
    | QE, Ir filter, Bayer filter, total. At 0.53 micron: QE = 50%,
    | IR filter transmission = 93%, green filter = 88%, for QE*IR*G
    ^^^^^^^^^^^^^^^^^^
    | = 41%.

    http://web.archive.org/web/20060831001100/http://www.ifa.hawaii.edu/~wang/misc/QE.jpg
    indeed shows that the red filter is better than the green filter
    .... it's better than 95%.

    Guess whom I believe more: someone who has a proven track
    record in that area and can quote relevant data --- or you.

    -Wolfgang
     
    Wolfgang Weisselberg, May 17, 2012
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  3. There are a lot of unspoken assumptions in that, e.g. a broad
    spectrum light source and none-too-wide colour filters.

    -Wolfgang
     
    Wolfgang Weisselberg, May 17, 2012
  4. There's also some median filter going on on long exposures with
    black frame reduction set to OFF in (some) Nikon cameras, perhaps
    to prevent hot pixels showing up quite as badly. Google for
    -Wolfgang
     
    Wolfgang Weisselberg, May 17, 2012
  5. Exactly. I tend to go all "fair witness" (a profession from Heinlein's
    _Stranger in a Strange Land_) when we get into these very precise
    detailed modes of talking.
     
    David Dyer-Bennet, May 17, 2012
  6. But it's a late additiona to the thread, the original reference was to
    the broad general class of noise reduction. (Just typoed that as "nose
    reduction".)
     
    David Dyer-Bennet, May 17, 2012
  7. Given that cluming is the mechanism by which different densities are
    produced, I wonder how good the tonality can be with Tech Pan, though.
    Absoutely. That's so ingrained I don't even think of it (and don't
    think to mention it to others).

    One of my heuristics for picking out the sharper shots (from adjacent
    very similar photos) when they look very similar to my eye is to pick
    the one with the larger jpeg. Kind of a tie-breaker when I can't find a
    reason to prefer one to the other for any other reason.
     
    David Dyer-Bennet, May 17, 2012
  8. Bruce

    PeterN Guest

    Excellent question.

    AFAIK, any difference would be through pattern recognition. Most noise
    reduction is based upon some type of color smudging.
    I have been able to reduce noise in CS5 by applying a slight surface
    blur to a layer.
     
    PeterN, May 17, 2012
  9. Bruce

    PeterN Guest

    Easily in the same sense that Columbus made and egg stand on its end.
     
    PeterN, May 17, 2012
  10. Bruce

    Trevor Guest

    Which you can't do if you use a filter on the camera in the first place, so
    your comparison now becomes meaningless!
    Either you want the freedom to adjust in post (shoot without a filter) or
    you don't!

    Trevor.
     
    Trevor, May 18, 2012
  11. To "I have 135mm tech pan that easily exceeds 24MP. Looking at
    ^^^^^^^^^^
    the negatives with a microscope proves it beyond any doubt.
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    Only wish I had a scanner capable of much higher rez to show
    it at its best." If you quote yourself, at least try to
    quote yourself correctly.

    What part of "Looking at the negatives with a microscope
    proves it beyond any doubt." is too hard for you? You wrote
    that sentence yourself! Did you outsmart yourself again?
    Oh wait: Noons rather would not provide any proof, because
    then his "easily exceeds 24MP" would be shown as what it is.

    More hot air.
    Not a shred of proof.
    Expected as much from such a hot air ballon. All blown up
    and belching flames and roaring ...

    People like me? People who've been there before there was a
    "google", before there was a "www"? What's next, you telling Ansel
    Adams how to photograph landscapes in black and white, because
    you did it long before it became "trendy" for people like A.A.?
    The postal service manages to move even negatives very long
    distances to a specific target in quite a short time. Much faster
    than that pony express you are used to.

    -Wolfgang
     
    Wolfgang Weisselberg, May 18, 2012
  12. Bruce

    John A. Guest

    Actually, I've heard of some folks using filters to balance the RGB
    histograms so that they don't have one or two channels relatively
    underexposed & noisy, then adjusting in post against a gray card or
    some such.
     
    John A., May 18, 2012
  13. Bruce

    John A. Guest

    Or you can be even more selective: http://registry.gimp.org/node/11742
     
    John A., May 18, 2012
  14. Bruce

    John A. Guest

    It's obvious that he wishes he could scan at higher resolution not to
    offer proof of the film's resolution to you or anyone else, but rather
    so that he could have digital versions of the photos at the resolution
    the film is capable of providing.

    That is why he considers your suggestion of photographing the
    microscope output to be idiocy: you totally missed the point of
    wanting to scan the film at higher res.
    He unintentionally outsmarted someone.
     
    John A., May 18, 2012
  15. Bruce

    Trevor Guest

    Only necessary if there is a reasonable imbalance in the first place, rather
    than wanting to *make* an imbalance in post.
    However if there is, and you might possibly want to change that later, then
    what you suggest would be a reasonable course of action.

    Trevor.
     
    Trevor, May 19, 2012
  16. Bruce

    John A. Guest

    Just a more thorough application of shoot-to-the-right, really.
     
    John A., May 19, 2012
  17. Bruce

    Noons Guest

    Wolfgang Weisselberg wrote,on my timestamp of 18/05/2012 2:31 PM:
    Yes. Your point?

    s/decrease/getlost/g
    See, I can write ed commands too....
    What's that got to do with your statement above, idiot?

    I don't have to provide any proof to the likes of you. This is not a court of
    law, moron. Get lost!

    From the likes of you.
    Yes. And with facts to back it up. Unlike you.
    Make sense, moron. WTH does all that mean?
    I won't send any negatives anywhere via post. It would be obvious to anyone else
    but you really need to have it detailed, don't you?
     
    Noons, May 19, 2012
  18. Bruce

    Noons Guest

    John A. wrote,on my timestamp of 18/05/2012 4:15 PM:
    Aw, c'mon! You know perfectly well that moronic arsehole trolls like "Wolfgang"
    are here with the express intention of distorting and disparaging anyone that
    doesn't belong to their little idiot Canon fan-club. Anything else is secondary!

    If it was only that the only point this idiot has missed...
    Narh! Canon fan-boy trolls are untiring in their stupidity.
     
    Noons, May 19, 2012
  19. Bruce

    Noons Guest

    David Dyer-Bennet wrote,on my timestamp of 18/05/2012 1:46 AM:
    No, it isn't. Not with Tech Pan or similar Pan films.
    You'd be surprised how many "experts" here and elsewhere claimed over the years
    jpg had enough detail to be used as a measure of detail-related size vis-a-vis
    tiff (or any non-lossy compression)...
    Bingo! What did I say? LOL!
    (narh, just joking: I'm aware you are doing a relative comparison between two
    jpgs of similar compression settings, not between a jpg and a tiff. That's
    fair. Just couldn't stop myself!).
     
    Noons, May 19, 2012
  20. "Pan" means "panchromatic", and all modern B&W films are panchromatic
    (tri-x, plus-x, panatomic-x, t-max).

    What Tech Pan is is an ultra-thin-emulsion film; not intended for
    pictorial photography at all, and not intended to produce a
    continuous-tone image in the first place. (Yes, with proper developers
    it clearly can produce useful continuous-tone images; haven't used it
    myself, but have seen plenty of examples.)
    Yep, two very-similar images, same dimensions, represented in the same
    compressed format. All those things being the same is critical to the
    size meaning anything at all (and even then it doesn't mean that much;
    if I prefer one by eye I ignore the sizes, it's just helpful to make up
    my mind when I can't find any other basis to prefer one photo).

    (The fact that I do this fairly frequently could be taken as a sign that
    I shoot too many copies of some of my photos!)
     
    David Dyer-Bennet, May 19, 2012
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