Bokeh at different focus distances 85L vs 35L

OK it seems that to a number of folks, the definitions in Photo Techniques in 1997 were apparently written by some jerk-offs who didn't know what they were talking about. So to quote a paper by Zeiss in 2010...

"Bokeh – properties of blurriness
"This image attribute is indeed more of an aesthetic and therefore subjective nature and cannot be described as simply with figures as it is the case with a well focused, sharp image. Thus its subtleties in lens tests play no important part sometimes. This is quite different in Japan: as well as figures for contrast, resolution etc., every test always includes examples of images with blurred flowers, leaves and other items which often act as the background to photographs. It is therefore perfectly right that the Japanese word “bokeh“ is used around the world as a collective term for all attributes of blurring.

"The Nature of Blurriness
"There is a particularly interesting point further to the left in the graphic above, about 0.4 mm in front of the focal point of the paraxial rays: there, the marginal rays seem to overtake those travelling more on the inside. The light cone is no longer ideally arranged, and we could say that the rays of light are 'confused.'
This is the original meaning of the Japanese word 'bokeh.'
There are so many rays that overlap in this zone of intersection that a ring with increased brightness results. This means that the circle of confusion is not a disk with homogenous brightness."

It is the intersection of these confused rays which combine into circles which look like other things we know, like onion rings, like donuts, etc. and due to the number of aperture blades in the diaphtam, these might appear as pentagonal, or hexagonal, or round shapes. All of these things create various observable manifestations of the bokeh seen in blurry backgrounds.

lens pirate;16443394]Dude..​.stop.

Seeing red and evaluating it are two different things. We ABSOLUTELY know what red is, we know how far the shade is from other shades, we can measure red, recreate it, and define it. What you actually percieve is subjective, but now what we can measure and red.

How you experience pain is subjective, the existence of pain is not. We know what things physically can be done to cause nearves to feel pain. Pain is electrical stimulation in a harsh way of real nerves and such. We can explain why it happens and cause it to happen. How you FEEL about it is your own subjective nature.

We can measure real things in the real world. Like i said, I would be happy to hear the other side admit that bokeh to them is only subjective and isn't real outside the mind. Then we could come up with a word for blur caused by shallow depth of field and it can be artsy too, but at least then we can all agree that it is real and all folks will have to do is decide if they value it or not, no need for gibberish.

It's the concept that bokeh only exist in the mind that makes it pointless. If it is only subjective you are really saying it doesn't exist. So it is they who are dealing with the meaningless.

uh, what?

That's right, and the artwork is a REAL things. You can describe it, and the only thing subjective about it is whether you like it, not it's actual existence.

You mean whether you like it is the subjective part. If I don't like it, that doesn't make it poof out of existence.

That's right, or the other way i would say it is, "it has bokeh, but I don't care for it subjectively"

Why go through all that. Simply tell me what constitutes bokeh, if it's only in the mind, then it doesn't really mean anything, so lets come up with a word for blur caused by dof, and there would be no need to discus subjective stuff only in the mind.

Love this and it explains it wonderfully. Bokeh is blurriness due to dof, ALWAYS, there is no bokeh which is NOT blurriness due to dof, EVER. It cannot exist apart from Blurriness due to dof, or in other words, blurriness due to depth of field and bokeh are equivalents, exactly the same thing. Your artistic response to it is subjective, having nothing to do with the existence of it. Anything you describe about it, like onion rings, is a QUALITY that this bokeh/blur has, a description OF the bokeh, it doesn't bring bokeh in to existence from nothing. Subjective stuff is meaningless, it's opinion. Remember the old saying about how everyone has an opinion, like you know what, and they all stink. Your subjective opinion is just that, it doesn't make blur in to bokeh.

Wilt wrote in post #16443420
OK it seems that to a number of folks, the definitions in Photo Techniques in 1997 were apparently written jerk-offs who didn't know what they were talking about. So to quote a paper by Zeiss in 2010...

"Bokeh – properties of blurriness
"This image attribute is indeed more of an aesthetic and therefore subjective nature and cannot be described as simply with figures as it is the case with a well focused, sharp image. Thus its subtleties in lens tests play no important part sometimes. This is quite different in Japan: as well as figures for contrast, resolution etc., every test always includes examples of images with blurred flowers, leaves and other items which often act as the background to photographs. It is therefore perfectly right that the Japanese word “bokeh“ is used around the world as a collective term for all attributes of blurring.

"The Nature of Blurriness
"There is a particularly interesting point further to the left in the graphic above, about 0.4 mm in front of the focal point of the paraxial rays: there, the marginal rays seem to overtake those travelling more on the inside. The light cone is no longer ideally arranged, and we could say that the rays of light are 'confused.'
This is the original meaning of the Japanese word 'bokeh.'
There are so many rays that overlap in this zone of intersection that a ring with increased brightness results. This means that the circle of confusion is not a disk with homogenous brightness."

It is the intersection of these confused rays which combine into circles which look like other things we know, like onion rings, like donuts, etc. and due to the number of aperture blades in the diaphtram, these might appear as pentagonal, or hexagonal, or round shapes. All of these things create various observable manifestations of the boken seen in blurry backgrounds.

guitarjeff wrote in post #16443472
Love this and it explains it wonderfully. Bokeh is blurriness due to dof, ALWAYS, there is no bokeh which is NOT blurriness due to dof, EVER. It cannot exist apart from Blurriness due to dof, or in other words, blurriness due to depth of field and bokeh are equivalents, exactly the same thing. Your artistic response to it is subjective, having nothing to do with the existence of it. Anything you describe about it, like onion rings, is a QUALITY that this bokeh/blur has, a description OF the bokeh, it doesn't bring bokeh in to existence from nothing. Subjective stuff is meaningless, it's opinion. Remember the old saying about how everyone has an opinion, like you know what, and they all stink. Your subjective opinion is just that, it doesn't make blur in to bokeh.

You continue to ignore what is explicitly written, and always reinterpet instead. You ignored the very first line which I quoted directly from the Zeiss paper:
"Bokeh – properties of blurriness
and you ignored the last line of that paragraph,
" It is therefore perfectly right that the Japanese word 'bokeh' is used around the world as a collective term for all attributes of blurring.

guitarjeff wrote in post #16443445
lens pirate;16443394]Dude..​.stop.

Seeing red and evaluating it are two different things. We ABSOLUTELY know what red is, we know how far the shade is from other shades, we can measure red, recreate it, and define it. What you actually percieve is subjective, but now what we can measure and red.



How you experience pain is subjective, the existence of pain is not. We know what things physically can be done to cause nearves to feel pain. Pain is electrical stimulation in a harsh way of real nerves and such. We can explain why it happens and cause it to happen. How you FEEL about it is your own subjective nature.

We can measure real things in the real world. Like i said, I would be happy to hear the other side admit that bokeh to them is only subjective and isn't real outside the mind. Then we could come up with a word for blur caused by shallow depth of field and it can be artsy too, but at least then we can all agree that it is real and all folks will have to do is decide if they value it or not, no need for gibberish.



It's the concept that bokeh only exist in the mind that makes it pointless. If it is only subjective you are really saying it doesn't exist. So it is they who are dealing with the meaningless.



uh, what?

That's right, and the artwork is a REAL things. You can describe it, and the only thing subjective about it is whether you like it, not it's actual existence.




You mean whether you like it is the subjective part. If I don't like it, that doesn't make it poof out of existence.

That's right, or the other way i would say it is, "it has bokeh, but I don't care for it subjectively"

Why go through all that. Simply tell me what constitutes bokeh, if it's only in the mind, then it doesn't really mean anything, so lets come up with a word for blur caused by dof, and there would be no need to discus subjective stuff only in the mind.

No we do not know what red is. That's the point. We assign the label "red" to a particular frequency of of EMR that falls near the lowest part of the EMR spectrum with in the limited range of the photo-receptors in our eyes. These receptors create electric signal that then gets interpreted by our brain. The brain creates a "image" of red with out any external reference or fact checking.

We have no idea what red looks like to each other. With out our minds there is NO SUCH THING AS COLOR. There is EMR...but color is a mental construct. So does it still exist?

You have been told what Bokeh means over and over. You just do not understand the answer.

I see that now. So then, what are the properties it requires in order for it to be called bokeh? Are those real or just made up in the mind by each individual?

at·trib·ute


something attributed as belonging to a person, thing, group, etc.; a quality, character, characteristic, or property: Sensitivity is one of his attributes.

Attributes of blurriness are real, describable, not subjective.

guitarjeff wrote in post #16443506
I see that now. So then, what are the properties it requires in order for it to be called bokeh? Are those real or just made up in the mind by each individual

I will state, for the second time, "It is the intersection of these confused rays which combine into circles which look like other things we know, like onion rings, like donuts, etc. and due to the number of aperture blades in the diaphram, these might appear as pentagonal, or hexagonal, or round shapes. All of these things create various observable manifestations of the bokeh seen in blurry backgrounds."

Donuts and onion rings solid disks and pentagons and hexagons and circles are all not subjective, they are both real and describable..

We know those parts of it that exist in the real world. Comparing it to other shades lets us label it RED regardless of how someone SUBJECTIVELY perceives it.

That doesn't mean the entirety of it resides only in the mind, or we would attempt to create something red and we would see a describable percentage of people that would see it as a green shade. Your own perception of red is subjective, that does not mean that there are no ways to measure red as opposed to different colors. Red is real in the outer world, beyond just exiting in the mind.

Wrong. We can take somethiung red and measure it's emr, or shade, find something else and predict we will see the same thing if the measurables are the same. So yes, it does. Your perception does not effect what is measurable between two people.

And I have explained over and over the definition is gibberish. How many times do I have to ask, DEFINE the quality it requires to be bokeh so that more than one person can always agree there is bokeh. If you can't, you are basically saying bokeh is only in the mond, or in other words, only imaginary, that it doesn't really exist beyond an opinion.

So are you saying that bokeh exist ONLY IN THE MIND and can be said to both exist and not exist depending on whether someone decides it has some subjective nature? Since you must be saying it is only in the mind since you cannot DESCRIBE the qualities which make it up, then it is nothing more than a fairytale, right?

Is it real or not, does it exist only in the mind OR NOT, please answer. In fact, many have already said it only exist in the mind in one way or another. So if that's true, it truly is meaningless.

Wilt wrote in post #16443519
I will state, for the second time, "It is the intersection of these confused rays which combine into circles which look like other things we know, like onion rings, like donuts, etc. and due to the number of aperture blades in the diaphram, these might appear as pentagonal, or hexagonal, or round shapes. All of these things create various observable manifestations of the bokeh seen in blurry backgrounds."

Donuts and onion rings solid disks and pentagons and hexagons and circles are all not subjective, they are both real and describable..

Then I AGREE So why are so many here saying it is subjective when you are clearly saying it is NOT subjective? Others said it's "THE QUALITY", but as you just said, that's not true. So I again say I am right and you agree, it is REAL and describable from one to another, measurable, and the only thing subjective is whether or not you actually like it, correct? I could care less if it's considered any blur due to dof, only that it is not all subjective and there is something definable from one to the other that everyone can agree on.

The silly staement I have heard over and over is that it is "The quality" as if this is something real for everyone. You now explain that bokeh IS REAL, outside the mind,and the mind only decides subjectively if they find it pleasing, correct?

guitarjeff wrote in post #16443546
We know those parts of it that exist in the real world. Comparing it to other shades lets us label it RED regardless of how someone SUBJECTIVELY perceives it.

That doesn't mean the entirety of it resides only in the mind, or we would attempt to create something red and we would see a describable percentage of people that would see it as a green shade. Your own perception of red is subjective, that does not mean that there are no ways to measure red as opposed to different colors. Red is real in the outer world, beyond just exiting in the mind.



Wrong. We can take somethiung red and measure it's emr, or shade, find something else and predict we will see the same thing if the measurables are the same. So yes, it does. Your perception does not effect what is measurable between two people.

And I have explained over and over the definition is gibberish. How many times do I have to ask, DEFINE the quality it requires to be bokeh so that more than one person can always agree there is bokeh. If you can't, you are basically saying bokeh is only in the mond, or in other words, only imaginary, that it doesn't really exist beyond an opinion.

So are you saying that bokeh exist ONLY IN THE MIND and can be said to both exist and not exist depending on whether someone decides it has some subjective nature? Since you must be saying it is only in the mind since you cannot DESCRIBE the qualities which make it up, then it is nothing more than a fairytale, right?

Is it real or not, does it exist only in the mind OR NOT, please answer. In fact, many have already said it only exist in the mind in one way or another. So if that's true, it truly is meaningless.

Lots of things only exist in the mind. Light with out triggering our photo-receptors and that signal being processed by our brains has no color. Without eyes to gather photons and brains to create images there is only darkness.

Temperature can also be said to not exist outside of the mind. Touch a ice cube or the ember of slow fire. The difference in the energy states between them has no intrinsic sensation. Its just the firing of nerve cells sending signals to the mind that then gets interpreted as temperature. Energy does exist. But the word "energy" fails terribly to describe how we experience its effects on us.

Try these two sentences.

That was container of relative to its surroundings high energy state organic matter.

Or

That was a great bowl of spicy hot chilli.

Are you going to stick to the absurd notion that those two sentences carry the same meaning? If so then you are so painted to into a rhetorical corner that your pride will never let you free.

Now that absurd false premise you left floating in the bowl that things that only exist on the mind are fairly tails and can be dismissed as meaningless is just such a huge disconnect with reality that it is hard to address.

have you not heard of
LOVE
Hatred
racism
jealousy
greed
pride

Where do those things exist but in the mind? Are they real?

The broad consensus in philosophy / neuroscience is that consciousness is a physical process. Whether experiences are knowledge or not is irrelevant, because knowledge of how two people experience "red" isn't required to know their experience is similar. All we need to know is if the physical structure of their eye & brain are similar. The photosensitive components of the eye are chemicals that react in a specific, measurable way to electromagnetic radiation every time. The processes in the brain that give rise to consciousness are the result of specific, measurable chemical and electrical interactions every time. So the argument that we can't know whether or not someone else experiences "red" in the same way is false. We can know and we do know that they do. This knowledge is distinct from knowledge of their experience of red, which we can't know. This latter bit is why people are so often confused by this subject. Further, saying there is no such thing as color "with our minds" isn't entirely accurate. Color "with our minds" is the chemical process from when the light enters our nervous system till when it is perceived by our brains. Suppose you were conversing with an alien life form that had completely different biology and thus their experience of "red" were different. It wouldn't be different because "red doesn't exist," it would be different because the chemical process from when the light entered their sensory apparatus till when it was perceived by their brains was different. Thus, they wouldn't be experiencing "red" at all, but something completely different.

So I believe Wilt has settled this and made bokeh UNDERSTANDABLE, measurable, definable.

I was wrong for saying it is only blur due to dof, and I have no problem with that as long as it is based on something real that is demonstrable. And those who were saying it is subjective and is "the quality" and such things as that were wrong too.

We have a breakthrough, bokeh is not simply an assessment or an opinion of value, it is a real phenomenon that exists outside the mind and can be described and shown from one person to another. Wow, another way of saying this is that it is a science, not a religion.

guitarjeff wrote in post #16443561
Then I AGREE So why are so many here saying it is subjective when you are clearly saying it is NOT subjective? Others said it's "THE QUALITY", but as you just said, that's not true. So I again say I am right and you agree, it is REAL and describable from one to another, measurable, and the only thing subjective is whether or not you actually like it, correct? I could care less if it's considered any blur due to dof, only that it is not all subjective and there is something definable from one to the other that everyone can agree on.

The silly staement I have heard over and over is that it is "The quality" as if this is something real for everyone. You now explain that bokeh IS REAL, outside the mind,and the mind only decides subjectively if they find it pleasing, correct?

Beautiful post, and reasonable.

LostArk wrote in post #16443609
The broad consensus in philosophy / neuroscience is that consciousness is a physical process. Whether experiences are knowledge or not is irrelevant, because knowledge of how two people experience "red" isn't required to know their experience is similar. All we need to know is if the physical structure of their eye & brain are similar. The photosensitive components of the eye are chemicals that react in a specific, measurable way to electromagnetic radiation every time. The processes in the brain that give rise to consciousness are the result of specific, measurable chemical and electrical interactions every time. So the argument that we can't know whether or not someone else experiences "red" in the same way is false. We can know and we do know that they do. This knowledge is distinct from knowledge of their experience of red, which we can't know. This latter bit is why people are so often confused by this subject. Further, saying there is no such thing as color "with our minds" isn't entirely accurate. Color "with our minds" is the chemical process from when the light enters our nervous system till when it is perceived by our brains. Suppose you were conversing with an alien life form that had completely different biology and thus their experience of "red" were different. It wouldn't be different because "red doesn't exist," it would be different because the chemical process from when the light entered their sensory apparatus till when it was perceived by their brains was different. Thus, they wouldn't be experiencing "red" at all, but something completely different.

LostArk wrote in post #16443609
The broad consensus in philosophy / neuroscience is that consciousness is a physical process. Whether experiences are knowledge or not is irrelevant, because knowledge of how two people experience "red" isn't required to know their experience is similar. All we need to know is if the physical structure of their eye & brain are similar. The photosensitive components of the eye are chemicals that react in a specific, measurable way to electromagnetic radiation every time. The processes in the brain that give rise to consciousness are the result of specific, measurable chemical and electrical interactions every time. So the argument that we can't know whether or not someone else experiences "red" in the same way is false. We can know and we do know that they do. This knowledge is distinct from knowledge of their experience of red, which we can't know. This latter bit is why people are so often confused by this subject. Further, saying there is no such thing as color "with our minds" isn't entirely accurate. Color "with our minds" is the chemical process from when the light enters our nervous system till when it is perceived by our brains. Suppose you were conversing with an alien life form that had completely different biology and thus their experience of "red" were different. It wouldn't be different because "red doesn't exist," it would be different because the chemical process from when the light entered their sensory apparatus till when it was perceived by their brains was different. Thus, they wouldn't be experiencing "red" at all, but something completely different.

Oh really? Then please describe what red looks like to me.

guitarjeff, I am relieved that you agree finally with what was posted.

I must point out that I am one of those fools who state "it is a quality, not a quantity" of blur. I use the word Quality to refer to an 'attribute' of blur or to a 'characteristic' of blur, whereas some folks use 'bokeh' as a synonym (which it is not) or to talk about 'how blurry' the background is (which it is not). I fully defend use of the word 'quality' in that context, which is Webster's Unabridged Dictionary's first definition of the word 'quality'!