Can we Collectively "know it" when only We Ourselves "see it" ? Locked

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Detail Man
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Can we Collectively "know it" when only We Ourselves "see it" ?
11 months ago

LTZ470 wrote:

markintosh13 wrote:

So far in _my_ scorekeeping, GB is making a more consistent, well defined and logical case ...

The photos I posted of the FZ200 disproves the diffraction theory easily, they are sharp not soft...and they are also sharper than MANY MANY of the bird shots posted here m43 or FF...

Hello, my good friend. I guess I missed the prior (not referenced herein) disscusion ? Link(s) ?

"A picture is worth a thousand words"

We are talking about in-camera JPGs with a bit of PP sometimes, right ? Remember that sharpening processes do (to some extent) improve the net composite (as viewed following in-camera and/or post processing) spatial frequency (MTF) response. Remember as well, that that perceptual metaphor "sharpness" has a myriad of objectively characterizable system behaviors surround "it" And there does exist any "Unified Sharpness Theory". Have a look at:

http://www.falklumo.com/lumolabs/articles/sharpness/

... or the much more nicely formatted PDF version (of the same paper) here:

http://www.falklumo.com/lumolabs/articles/sharpness/ImageSharpness.pdf

All talk and no photos to back it up...doesn't prove anything to me and many others...the proof is in the photos guys, you can do ALL the calculations ... you want...

Remember that individual human "contrast sensitivy function" is part of the (subjective) prisms that we each "gaze through". That function changes with overall visual acuity, as well as absoulte light-level of the image and the viewing enviromnent, and is also different for different specific color-contrasts (and none of this gets better around, and past, our tender ages ...

No I do not believe the FZ200 suffers from diffraction until f/4, maybe just under f/4 at say f/3.7-3/8...

How do we define the point at which our visualization as viewers "suffers" ? I don't know how a particular piece of music sounds to your aesthetic mind - and the same (if not more so) is true where it comes to vision (which I have read consumes something resembling 70% of our cerebral grey-matter in order to process (in still highly mysterious ways probably never comprehensively "knowable".

Note that perceived "sharpness" seems (to some researchers) to surround the overall shape (as well as the extension into upper spatial frequencies) of the spatial frequency function of a viewed image itself. "Resolution" is not the same thing as perceived "sharpness". It is clearly deeper than that, and seemingly yet not well characterized by specific objective measures.

Truly, the "bottom line" (all we have for "spectacles") is how the image "looks" (to our own eyes) - and not a concrete objective "fact" to be found through well established numerical analysis.

NOW prove me wrong with photos ... The burden of proof is upon you to prove with actually photos...

We can't step into each others' heads. We all (for all that we "know") see a different perspective of (rhetorical) "elephants". It (may) only look much like an "elephant in" (your own) "living room".

GB is (one of) the (sharpest) posters on these forums. I have stated, however that the sum total effects of lens-system Diffraction as combined with other important factors are quite complicated (and result from a number of individual contributing system elements). Here is a thread where I investigate and display some spatial frequency response (MTF) models for how those effects can manifest themselves. Check it out. Plenty of various complex factors involved:

http://www.dpreview.com/forums/thread/3475094

ALL the photos I have posted from FZ200 prove your Diffraction theory wrong in that the photos will be soft making it an irrelevant mute point ... that's why I specifically used those FZ200 shots ...

Don't know your interlocutor's "diffraction theory". Try my own "diffraction modelling" on for size.

Remember that what are own individual eyes see are influenced by unique and subjective factors:

http://www.dpreview.com/forums/post/51218344

... such that measured numbers may not always bear out our personal visual perceptions. In the above case, when R,G, and B channels were combined, those images had virtually identical "greyscale" values. The relative balance between the colors caused your (and perhaps other) eyes to surmise otherwise. My own right eye's color vision is rather compromised. We may as a result see the world differently. There seems to be no objectively agreeable "true" and "false" in these things. They are inherently subjective (and mysterious even to ourselves) value-judgments.

"Sharpness" is a term like "brightness' or the phrase "image quality". These terms do not correspond to presently "determinable objective facts". There exists no "baseline anchoring".

And in that case, there was a numerical metric that could be measured. Here their exists no such simple objective definition for the subjective perceptual value-judment of adequate "sharpness".

DM ...

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