1.5X Sensors VS. Full Frame and other questions...

Discussion in 'Digital Photography' started by Progressiveabsolution, Apr 27, 2006.

  1. SNIP
    Isn't that exactly the same, only on the opposite side of the lens and
    thus scaled by the magnification factor?

    Bart
     
    Bart van der Wolf, May 4, 2006
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  2. No, I didn't. I simply commented on a particular portion of interest. Live
    whatever pipe dream you like, it doesn't matter to me. But the original
    picture is NOT sharp in the spire ... period.
    Not it doesn't. I showed the image at the specifications stored in its
    metadata. The entire image fit on a 1280x1024 monitor. Are you indicating
    that the image has fewer pixels than what is on a 1280x1024 monitor? I dare
    say I didn't even get to 100%!
     
    Thomas T. Veldhouse, May 4, 2006
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  3. You are starting to sound like an irrational fan boy! He didn't say he shot
    at high ISO, he said large apeture. The paranthesis above indicate that he
    might use an alternative of raising the ISO. If you have read this thread, it
    is clearly in the context that he has suggested doing this in the past. What
    Mark offered was simply an analysis and was not a "bogus claim".
     
    Thomas T. Veldhouse, May 4, 2006
  4. BTW .. nice gallery. You do seem to have taken some nice images judging by
    the content of your gallery.
     
    Thomas T. Veldhouse, May 4, 2006
  5. You say "No.", and then describe it as *exactly* what I said it
    was.
    Yes, the "900x600 image display" is cited above. (Note too that
    it makes *no* difference whether this is a "browser" or an
    "editor", or something else.)
    So the fact that you have a 900x600 window, looking at a section
    of an image that might be anything from 900x600 on up to
    9000x6000 or larger makes no difference, you say? It *does*.
    Obviously I did hit it almost dead on. From what you say, you have
    a slightly higher resolution screen and used as physically smaller
    window than my example. The relationship is exactly the same...
    It makes no difference if that is a web browser, an image
    viewer, an image editor, or a paper print. The resolution and
    physical size of the display device have the same relationship
    to the number of pixels in the image.
    You are claiming is that a "pixel-for-pixel" view that looks
    identically "sharp" for image A and image B means they are in
    fact equally sharp.

    (But of course if image A is a "100% crop" from an original that
    is 1280x900 and image B is from an image that is 9000x6000 then
    despite the fact that your display looks identical, if we print
    them at 6"x4" they both look fine and if we print them a 6'x4'
    one is still sharp and the other looks hidious.)
     
    Floyd L. Davidson, May 4, 2006
  6. Except that it is.
    The entire 2592x3888 image fit on your 1280x1024 monitor. Okay... ;-)

    Regardless, it is obvious why both you and Mark believe the image is
    not sharp. You are looking at a 40"x60" enlargement and evaluating
    it as if it were an 8"x10".
     
    Floyd L. Davidson, May 4, 2006
  7. Progressiveabsolution

    Alfred Molon Guest

    My shot was 1/50s at 120mm.

    It is possible to go down to 2/f (in my case 2.4/f) and get sharp shots,
    if you are careful. Perhaps you also have to use a camera with no
    swinging mirror (i.e. no DLSR).
     
    Alfred Molon, May 4, 2006
  8. Progressiveabsolution

    Alfred Molon Guest

    Looks good. What was the exposure time and focal length ?
     
    Alfred Molon, May 4, 2006
  9. Progressiveabsolution

    Alfred Molon Guest

    Here are some more shots I just took:

    http://www.molon.de/P5041152.JPG
    1/30s, F4.8, 120mm equiv., handheld
    Here we are at 4/f - can't believe the shot came out sharp.


    http://www.molon.de/P5041160.JPG
    1/5s, F14, 120mm equiv., tripod
    This one is a little bit sharper but not by much.

    My guess is that the unsharpness at the edges of the first image is
    caused by the shallow DOF, because the corner of the yellow-white roof
    in bottom right corner is sharp. So the lens is probably ok at the tele
    end wide open, there is just a lack of DOF.

    BTW, in both shots the sky is much less noisy.
     
    Alfred Molon, May 4, 2006
  10. Progressiveabsolution

    wsb Guest


    Compare the antennas in the upper right corner.

    Wes
     
    wsb, May 4, 2006
  11. Progressiveabsolution

    Mark² Guest

    8x10? Who said anything about 8x10???
    I printed the following shot at 17"x25" (and it is THIS shot Alfred first
    went on his "no tripod" rant about):
    http://www.pbase.com/markuson/image/58828940/original
    That's plenty big...to need the sharpness I am describing.
    If you don't think his spire troubles would show up in a 17x25, you're
    beyond help.
    -M²
     
    Mark², May 5, 2006
  12. Progressiveabsolution

    ASAAR Guest

    So it's Alfred that's ranting, is it? From what I've seen, he's
    gone out of his way to be polite and in several cases has agreed
    with those pointing out minor flaws in his image. If the same image
    was submitted by someone else, with "Canon" substituted in the EXIF
    data, you probably would have been quite complimentary.

    No, it's you, once again resorting to personal attacks when people
    don't roll over and agree with your distorted assertions.
     
    ASAAR, May 5, 2006
  13. Progressiveabsolution

    Mark² Guest

    You have proven my point beautifully.

    I submit one very simple indicator of the kind of detail you throw away by
    hand-holding...which forced you to use a large aperture.
    1. Look at the mountain bike's tires on the right in the first f4 shot at
    full resolution. What do you see?
    Answer: Nearly-smooth, blurry tires.
    http://www.pbase.com/markuson/image/59680814/original
    Now...look at the same tires in the f14 shot.
    http://www.pbase.com/markuson/image/59680818/original
    Wow!
    There are clear and distinct KNOBS on those tires!
    They aren't street tires after all!
    They now appear as they really are...KNOBBY TIRES...All because you took the
    time to use a tripod...which, in turn, allowed you to use an aperture that
    could render fine detail!

    I rest my case... :)
    -But gaining that critical DOF is a (if not THE) primary reason for using a
    tripod. Its not JUST motion blur in general (which would imply that simply
    opening the aperture up solves everything...which it does't)...it is the
    *slow shutter* that tripods allow, due to the stability for handling the
    accompanying slow shutter...that handholding simply cannot provide under
    similar circumstances. This is the ability to use the slow shutter that
    enables the small aperture. Stopping down is your best bet for utilizing
    the full sharpness potential of that (or nearly any other) lens, and you
    have demonstrated this point here.
    True...though the sky in this shot is nearly colorless, meaning its less
    prone to visible noise.
     
    Mark², May 5, 2006
  14. Progressiveabsolution

    Mark² Guest

    LOL, ASAAR!
    I set up my laptop for NG access a few minutes ago...so I have no kill-file
    residents on this machine yet...and so here you are...making the sort of
    goofy hyper-sensitive comments about "personal attacks" that landed you in
    the klink file to begin with.

    I'll give you one chance to quote what you consider a personal attack...
    What? The "beyond help" thing?? If so... Oh brother.
    It was clear enough... If he can't concede that these things become clear
    and noticeable at 17x25, then there's little left to say that could ever
    bring him around. Save'??
    Simple, yet your dander is already up.
    Toughen up, for crying (literally) out loud!
     
    Mark², May 5, 2006
  15. Progressiveabsolution

    Mark² Guest

    Who ever claimed that this was only about camera shake?
    Tripods allow the use of tiny apertures that would render very shaky images
    if hand-held. Part of this whole concept is the fact that by using a
    tripod, one can shoot at apertures (which take advantage of nearly all
    lenses best performance re: sharpness) that require long shutter
    peeds. -Long shutter speeds mean hand-holding is a problem. The two are
    forever linked, meaning its rather silly to assume that hand-shake and
    aperture/shutter considerations are somehow entirely separate from each
    other. One leads to the other. Fast shutters lead to large aperture, and
    tehreverse is also true. As it relates to hands vs. tripod, there is simply
    no logical or factual dispute that a tripod offers this advantage FAR beyond
    hand-held limitations allow. The shot that started this was my half-done
    shot. It was shot at f20, and 1/13th of a second. While one could
    hand-hold the shot at that (or any) aperture, the trade-off in sharpness (or
    ISO cranking) is beyond dispute by any reasonable photog. Attempting to
    limit this conversation to motion blur...but at completely different
    apertures...and therefore better/worse sharpness characteristics...is just
    silly. The two are forever linked.

    -Mark
     
    Mark², May 5, 2006
  16. Progressiveabsolution

    Mark² Guest

    Sharp? You can make that statement ONLY as it relates to movement. But
    there are other contributing factors in the creation of critically sharp
    images. Much of the whole tripod advantage lies in the fact that you are
    freed to use apertures that maximize sharpness. You cannot reduce apertures
    during handholding to anything close to what you can with a tripod. The
    result of this hand-held limitation means you're stuck either shooting big
    apertures (leading to less sharpness, and other significant optical
    side-effects) or higher ISO (leading to noise and loss of detail). If this
    was ONLY about motion blur, rather than what I've termed, "critical
    sharpness" from the very beginning...you're missing most of the point. The
    entire combination of capabilities lead to a mixture of factors that do
    indeed produce sharper results.
    Here again, you demonstrate that you're missing key factors.
    Had he used a tripod, he could have utilized smaller apertures that enable
    sharpness that he can't/didn't obtain.
     
    Mark², May 5, 2006
  17. : This is wholly incorrect. There is no such relationship between object
    : detail size and sensor resolution. Your assertion completely overlooks
    : the magnification provided by the lens. Photomicrographs can show
    : details down to around 250 nanometres - about 1/32 of the typical pixel
    : pitch of a DSLR - and this limit only exists because of the diffractive
    : nature of light, not because of sensor limitations. (With appropriate
    : optics, the 250 nm resolution image could even be projected on, and
    : resolved by, your extreme hypothetical sensor.)

    But I am speaking about the relationship between the maximin detail in
    relation to the size of the image. So in your example, if the entire image
    is of an area 1/4 inch square, and there are 1 million pixel to the image
    the smallest detail that can be resolved is one that is 1 millionth of
    that 1/4 inch square. You are correct that the lens will determine the
    size of the image, but the sensor will determine the detail resolvable
    within that image. A one million pixel sensor will not be able to
    accurately resolve details that are smaller than a single sensor within
    the image.

    You are correct that the lens will determin what that single sensor
    equates to in the real world. Using a wide angle lens at a long distance
    that single sensor may equate to a 2' square. On the other end, a
    telephoto lens at short distance may mean that the sensor is resolving a
    square 1/100th inch. And using a macro or a microscopic lens this single
    sensor would be resolving an area that is in angstroms. But the smaller
    the detail resolvable will also effect the total size of the image in
    proportion. No CSI type silliness that resolves a clear license plate off
    a wide angle lens from a mile away from a single pixel on the image. :)

    Randy

    ==========
    Randy Berbaum
    Champaign, IL
     
    Randy Berbaum, May 5, 2006
  18. Progressiveabsolution

    Alfred Molon Guest

    You could have increased the ISO to 400 and obtained a sharp handheld
    shot at 1/50s (and with noise low enough since your camera has still low
    noise levels at ISO 400).

    1/50s is fast enough for a sharp handheld shot at 38mm equiv. focal
    length, which I have proven with the handheld shots I've posted.
     
    Alfred Molon, May 5, 2006
  19. Progressiveabsolution

    ASAAR Guest

    That's your problem, not mine, Colonel Klink. Whether you filter
    or not, I still reply to your messages as appropriate, as you've
    noticed several times already. Sometimes you're praised, sometimes
    you're panned, but most of the time I read them and move on to the
    others, even those that are liberally adorned with the snide
    comments you so favor.

    One point for you. If you couldn't figure it out, or pretended
    that you didn't know what I was referring to, it would be you that
    was "beyond help".

    What I understand, kemo sabe, is that when you get in these
    extended discussions, and when you're saddled with a losing
    position, you often resort to snide comments and insults, such as
    the one above. That may be your way of trying to provoke
    retaliation, allowing you to (ungracefully) end the discussion, and
    proudly proclaim yet another addition to your klink file.

    Let's see now. You insult someone. You're called on it. You
    then cry about it. Who needs to toughen up? Not I, Mook²y poo. I
    don't need no steenking klink file. :)
     
    ASAAR, May 5, 2006
  20. Progressiveabsolution

    Alfred Molon Guest

    Well... you wrote that at 1/f it is not possible to obtain a handheld
    shot with no camera shake. This is clearly not the case. I've obtained
    handheld shots with no visible camera shake even at 4/f !
     
    Alfred Molon, May 5, 2006
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