Math is an abstract idealization, when you attempt to use it to prove anything in the real messy world you are are forced to make assumptions and approximations. When your math proves something that is wrong, it only means that your assumptions of the problem were wrong, not that the math was wrong.
Exactly! Notice I did not say: "We can use mathematics to prove that math is untrue". rather I said: "We can use mathematics to "prove" all kinds of things which aren't [actually] true."
mh2000 wrote:
True, but instead of "sharpness" I'd say that resolution is probably more important... IE. large prints from a larger format camera with higher resolution will be much more important than small changes in lens sharpness on a smaller camera. A mediocre lens on a LF body will produce better large prints than a top lens mounted on a FF DSLR.
Any image sufficiently in focus will look sharp if you decrease it to a small enough resolution. To go back to the original post, is was observed that some of Ansel Adams' prints appeared soft. Had they been printed smaller, they would likely have appeared much sharper.
But we're mostly playing in the realm of semantics at this stage anyway. Whether we want to talk about "sharpness" or "resolution" or "resolving power" or "MTF" or any other closely related terms...the main point I want to make is that while you don't need expensive gear to make good photographs, you do need a certain level of gear if you are interested in making a certain types of photographs.
In a broad sense good photography doesn't need to rely on sharpness, any more than good sharpness is responsible for creating a good photo. But photography which emphasizes a high level of detail does indeed rely on sharpness.
mh2000 wrote:
Math is an abstract idealization, when you attempt to use it to prove anything in the real messy world you are are forced to make assumptions and approximations. When your math proves something that is wrong, it only means that your assumptions of the problem were wrong, not that the math was wrong.
when you use math to prove anything other than an abstract idealization it ceases to be math, it becomes engineering, physics, or (god forbid) economics. anything you can prove with math IS true (and probably not relevant to the real world).
Sure, that's what I meant, all you can prove with math is math.
I think the most retarted example of "proving" something that is wrong is that by some simple theory, a bumble bee cannot fly...
sebboh wrote:
when you use math to prove anything other than an abstract idealization it ceases to be math, it becomes engineering, physics, or (god forbid) economics. anything you can prove with math IS true (and probably not relevant to the real world).
I was responding to the "If your artistic vision is to have large prints with exquisitely fine details" portion and this takes resolution to support the detail. No matter how sharp an image, when printed to 72dpi on a print, you will not have a sharp looking image when viewed at a close distance.
You need a minimum resolution to print to a certain size. You need sharpness and resolution to produce fine detail.
artd wrote:
Any image sufficiently in focus will look sharp if you decrease it to a small enough resolution. To go back to the original post, is was observed that some of Ansel Adams' prints appeared soft. Had they been printed smaller, they would likely have appeared much sharper.
But we're mostly playing in the realm of semantics at this stage anyway. Whether we want to talk about "sharpness" or "resolution" or "resolving power" or "MTF" or any other closely related terms...the main point I want to make is that while you don't need expensive gear to make good photographs, you do need a certain level of gear if you are interested in making a certain types of photographs.
In a broad sense good photography doesn't need to rely on sharpness, any more than good sharpness is responsible for creating a good photo. But photography which emphasizes a high level of detail does indeed rely on sharpness.
mathematics |maθ(ə )ˈmatiks|
plural noun [usu. treated as sing. ]
the abstract science of number, quantity, and space. Mathematics may be studied in its own right ( pure mathematics), or as it is applied to other disciplines such as physics and engineering ( applied mathematics).
• [often treated as pl. ] the mathematical aspects of something : the mathematics of general relativity.
It can't be much clearer than that.
And of course:
mathematician |ˌmaθ(ə )məˈti sh ən|
noun
an expert in or student of mathematics.
All things are not equal, but all things matter to some extent.
LoneShadow wrote:
The quality of photos seen in 7d/5d compared to 50d for the same lens is much better. Would this be just extra resolution from the sensor?
And to apply math to anything real you have to make assumptions, this is where the errors lie. Some assumptions are better than other, some give useful predictions, others garbage.
Bifurcator wrote:
It can't be much clearer than that.
Bifurcator wrote:
I thought we already established that they basically are the same thing and that "sharpness" doesn't actually exist as a quantifiable attribute? In the Bifurcator Photographic Dictionary anyway, resolution and "sharpness" are two hairs of the same horse.
The physical units of resolution and contrast are different, these quantities are thus not the same. Both are quantifiable, unlike sharpness, which is a subjective perception.
Whenever resolution or contrast is being quantified, the used definition/criterion should be mentioned.
If there exists a formal definition of microcontrast, someone did a good job hiding it. I doubt the Bifurcator Photographic Dictionary offers a definition, but it doesn't really matter since it lacks authority.
I consider "sharpness" to be the combined effect of resolution and contrast. I think resolution is the most basic property for sharpness, with contrast modifying the apparent resolution, or sharpness. YMMV.
mh2000 wrote:
I was responding to the "If your artistic vision is to have large prints with exquisitely fine details" portion and this takes resolution to support the detail. No matter how sharp an image, when printed to 72dpi on a print, you will not have a sharp looking image when viewed at a close distance.
I'm not disagreeing. You need the resolution on the back end (sensor or film). You also need the resolving power on the front end (lens).
Bifurcator wrote:
I thought we already established that they basically are the same thing and that "sharpness" doesn't actually exist as a quantifiable attribute? In the Bifurcator Photographic Dictionary anyway, resolution and "sharpness" are two hairs of the same horse.
Toothwalker wrote:
The physical units of resolution and contrast are different, these quantities are thus not the same. Both are quantifiable, unlike sharpness, which is a subjective perception.
Whenever resolution or contrast is being quantified, the used definition/criterion should be mentioned.
If there exists a formal definition of microcontrast, someone did a good job hiding it. I doubt the Bifurcator Photographic Dictionary offers a definition, but it doesn't really matter since it lacks authority.
You question the authority of the BPD? What are you a Learian devotee from the 60's
