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Smaller sensors = shallower DOF? No way, right?

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MrBrightSide

MrBrightSide

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A frequently repeated fact on these forums and the foundation of the whole DPReview approach to reviewing is that larger sensors = shallower depth of field and vice versa.

Go to 1:57 on the tape where this editor from Petapixel is calling "BS" and says that "technically speaking smaller sensors have a shallower depth of field because they have a higher pixel density." He then goes on to demonstrate a bunch of stuff we already know.

It is this comment on smaller sensors that has me irked. What he is saying invalidates much of the accumulated wisdom here in just the same way Martin Luther discredited the Catholic view of salvation in 1517.

So who do we believe? The long legacy of statements about depth of field vs. sensor size and the related charts of equivalent f/stop? Or this outsider from a competing website who seems Hell bent on undoing years of hard work.
 
Last edited:
J A C S said:
MrBrightSide said:
And yet the greatest scientific breakthroughs in the Middle Ages were made by Arab and Persian scholars. Who knows, without the many Islamic innovations in math we might still be painting on cave walls with ox blood instead of taking photos through exquisite optics.
Click to expand...
I do not think that Newton was a Muslim.
Click to expand...
Presumably he also mastered time travel, so that he could do his work in the Middle Ages?
 
bobn2 said:
D Cox said:
Different historical period. I'm talking about modern theologians.
Click to expand...
Not sure why you picked on 'Muslim'. There are plenty of fundamentalist theologians from other religions who would also deny those.
Click to expand...
Islam is influenced by contemporary thought as much as any other mainstream religion. We can see the same influences in Christianity, Buddhism, and Judaism, as well as many other religious/philosophical movements.

In Christianity, similar lines of thinking led to the Reformation. William of Occam, for example, was highly influential in the late Medieval period in Europe, and his "new theology" was particularly valued by Luther and Henry VIII. William wanted to simplify theology, thinking that the complexities of Catholicism wasn't helpful. In particular he wanted to strip away the influence of Greek philosophy: Pythagoras, Plato, Aristotle, and others were pagans, and so what right did they have to influence Christianity? As an earlier theologian wrote, "What does Athens have to do with Jerusalem?" Doubts about Greek thought occured at the same time in Islam.

But anyway, William proved influential in a number of things: his 'solas' (faith alone, scripture alone, grace alone, etc.); the philosophies that eventually became known as nominalism, conceptualism, and relativism; the supremacy of the State over the Church; and his general simplifying principle known as Occam's Razor. His theories also led to notions of radical individualism, and consequently, totalitarianism, as well as both fundamentalism and liberalism.

But it's the de-hellenization part which is of particular interest, the stripping away of the influence of Greek philosophy. But what was lost? The general physical notions of the Pythagorean and Socratic schools are that the cosmos is an objective reality, is well-ordered, it operates according to its own immanent laws, and that it is also intrinsically knowable - although this knowledge is difficult - and that mathematics is the true model of the material world. But these principles, they argue, also apply to the inner world of humans: we are a microcosm, or 'little cosmos'. But Modern de-hellenized thought will often reject one or another of these: either affirming the radical freedom of humans or the radical freedom of God, or both. If reason contradicts faith, then reason can be rejected; likewise, if reason contradicts human liberty, then reason can be rejected as well. This attitude is widespread throughout Western society, not just with fundamentalists but also amongst the smart set as well.
 
Mark Scott Abeln said:
If reason contradicts faith, then reason can be rejected; likewise, if reason contradicts human liberty, then reason can be rejected as well. This attitude is widespread throughout Western society, not just with fundamentalists but also amongst the smart set as well.
Click to expand...
My Philosophy 101 professor said that he couldn't pass a logic class so he couldn't get his degree in philosophy. So, he switched to a university that didn't require him to pass a logic class to get a philosophy degree. One of the other students remarked, "That was logical."

:-D
 
Great Bustard said:
My Philosophy 101 professor said that he couldn't pass a logic class so he couldn't get his degree in philosophy. So, he switched to a university that didn't require him to pass a logic class to get a philosophy degree. One of the other students remarked, "That was logical."

:-D
Click to expand...
Buhwahaha!
 
Mark Scott Abeln said:
bobn2 said:
D Cox said:
Different historical period. I'm talking about modern theologians.
Click to expand...
Not sure why you picked on 'Muslim'. There are plenty of fundamentalist theologians from other religions who would also deny those.
Click to expand...
Islam is influenced by contemporary thought as much as any other mainstream religion. We can see the same influences in Christianity, Buddhism, and Judaism, as well as many other religious/philosophical movements.

In Christianity, similar lines of thinking led to the Reformation. William of Occam, for example, was highly influential in the late Medieval period in Europe, and his "new theology" was particularly valued by Luther and Henry VIII. William wanted to simplify theology, thinking that the complexities of Catholicism wasn't helpful. In particular he wanted to strip away the influence of Greek philosophy: Pythagoras, Plato, Aristotle, and others were pagans, and so what right did they have to influence Christianity? As an earlier theologian wrote, "What does Athens have to do with Jerusalem?" Doubts about Greek thought occured at the same time in Islam.

But anyway, William proved influential in a number of things: his 'solas' (faith alone, scripture alone, grace alone, etc.); the philosophies that eventually became known as nominalism, conceptualism, and relativism; the supremacy of the State over the Church; and his general simplifying principle known as Occam's Razor. His theories also led to notions of radical individualism, and consequently, totalitarianism, as well as both fundamentalism and liberalism.

But it's the de-hellenization part which is of particular interest, the stripping away of the influence of Greek philosophy. But what was lost? The general physical notions of the Pythagorean and Socratic schools are that the cosmos is an objective reality, is well-ordered, it operates according to its own immanent laws, and that it is also intrinsically knowable - although this knowledge is difficult - and that mathematics is the true model of the material world. But these principles, they argue, also apply to the inner world of humans: we are a microcosm, or 'little cosmos'. But Modern de-hellenized thought will often reject one or another of these: either affirming the radical freedom of humans or the radical freedom of God, or both. If reason contradicts faith, then reason can be rejected; likewise, if reason contradicts human liberty, then reason can be rejected as well. This attitude is widespread throughout Western society, not just with fundamentalists but also amongst the smart set as well.
Click to expand...
I think that we need to get the timeline straight. al-Khwarizmi lived from 780-850AD. William of Ockham lived from 1287-1347AD. That's 500 years difference, another completely different period.
 
bobn2 said:
I think that we need to get the timeline straight. al-Khwarizmi lived from 780-850AD. William of Ockham lived from 1287-1347AD. That's 500 years difference, another completely different period.
Click to expand...
I thought the discussion was about fundamentalist theologians? William of Occam pretty much invented the field, along with his rejection of Greek Philosophy. Muslim scholars also had a high regard for the Greeks until about the same time as William.

Part of the decline of scholarship in that era is undoubtedly due to the Black Death, which may have killed off something like 90% of university faculties.
 
bobn2 said:
Mark Scott Abeln said:
bobn2 said:
D Cox said:
Different historical period. I'm talking about modern theologians.
Click to expand...
Not sure why you picked on 'Muslim'. There are plenty of fundamentalist theologians from other religions who would also deny those.
Click to expand...
Islam is influenced by contemporary thought as much as any other mainstream religion. We can see the same influences in Christianity, Buddhism, and Judaism, as well as many other religious/philosophical movements.

In Christianity, similar lines of thinking led to the Reformation. William of Occam, for example, was highly influential in the late Medieval period in Europe, and his "new theology" was particularly valued by Luther and Henry VIII. William wanted to simplify theology, thinking that the complexities of Catholicism wasn't helpful. In particular he wanted to strip away the influence of Greek philosophy: Pythagoras, Plato, Aristotle, and others were pagans, and so what right did they have to influence Christianity? As an earlier theologian wrote, "What does Athens have to do with Jerusalem?" Doubts about Greek thought occured at the same time in Islam.

But anyway, William proved influential in a number of things: his 'solas' (faith alone, scripture alone, grace alone, etc.); the philosophies that eventually became known as nominalism, conceptualism, and relativism; the supremacy of the State over the Church; and his general simplifying principle known as Occam's Razor. His theories also led to notions of radical individualism, and consequently, totalitarianism, as well as both fundamentalism and liberalism.

But it's the de-hellenization part which is of particular interest, the stripping away of the influence of Greek philosophy. But what was lost? The general physical notions of the Pythagorean and Socratic schools are that the cosmos is an objective reality, is well-ordered, it operates according to its own immanent laws, and that it is also intrinsically knowable - although this knowledge is difficult - and that mathematics is the true model of the material world. But these principles, they argue, also apply to the inner world of humans: we are a microcosm, or 'little cosmos'. But Modern de-hellenized thought will often reject one or another of these: either affirming the radical freedom of humans or the radical freedom of God, or both. If reason contradicts faith, then reason can be rejected; likewise, if reason contradicts human liberty, then reason can be rejected as well. This attitude is widespread throughout Western society, not just with fundamentalists but also amongst the smart set as well.
Click to expand...
I think that we need to get the timeline straight. al-Khwarizmi lived from 780-850AD. William of Ockham lived from 1287-1347AD. That's 500 years difference, another completely different period.
Click to expand...
RAMBAM, Moreh Nevukhim, a hundred years earlier than William of Ockham.
 
Mark Scott Abeln said:
bobn2 said:
I think that we need to get the timeline straight. al-Khwarizmi lived from 780-850AD. William of Ockham lived from 1287-1347AD. That's 500 years difference, another completely different period.
Click to expand...
I thought the discussion was about fundamentalist theologians? William of Occam pretty much invented the field, along with his rejection of Greek Philosophy. Muslim scholars also had a high regard for the Greeks until about the same time as William.

Part of the decline of scholarship in that era is undoubtedly due to the Black Death, which may have killed off something like 90% of university faculties.
Click to expand...
Don't forget Hulagu Khan. His warriors destroyed House of Wisdom in 1258. That had a profound effect, the library was lost, the loss is comparable, at minimum, to that from the destruction of the Library of Alexandria, though there is a difference: the destruction of the Library of Alexandria happened during the course of many years, not in one week.
 
Iliah Borg said:
RAMBAM, Moreh Nevukhim, a hundred years earlier than William of Ockham.
Click to expand...
Moses Maimonides was definitely pro-Greek philosophy. William of Occam rejected Greek thinking, and he pretty much marks the beginning of modern subjectivist thought.
 
Mark Scott Abeln said:
bobn2 said:
I think that we need to get the timeline straight. al-Khwarizmi lived from 780-850AD. William of Ockham lived from 1287-1347AD. That's 500 years difference, another completely different period.
Click to expand...
I thought the discussion was about fundamentalist theologians? William of Occam pretty much invented the field, along with his rejection of Greek Philosophy. Muslim scholars also had a high regard for the Greeks until about the same time as William.

Part of the decline of scholarship in that era is undoubtedly due to the Black Death, which may have killed off something like 90% of university faculties.
Click to expand...
OK, my misunderstanding as to what the discussion was about.
 
Iliah Borg said:
Mark Scott Abeln said:
Part of the decline of scholarship in that era is undoubtedly due to the Black Death, which may have killed off something like 90% of university faculties.
Click to expand...
Don't forget Hulagu Khan.
Click to expand...
Forget? I never knew about him in the first place.
Iliah Borg said:
His warriors destroyed House of Wisdom in 1258. That had a profound effect, the library was lost, the loss is comparable, at minimum, to that from the destruction of the Library of Alexandria, though there is a difference: the destruction of the Library of Alexandria happened during the course of many years, not in one week.
Click to expand...
That’s unfortunate.

I’m reminded of Boethius, after Rome had been taken over by barbarians, who translated as many Greek works as he could into Latin, since there literally was no one else that he knew of who could read Greek. He was executed before he could translate Aristotle.
 
Mark Scott Abeln said:
Iliah Borg said:
RAMBAM, Moreh Nevukhim, a hundred years earlier than William of Ockham.
Click to expand...
Moses Maimonides was definitely pro-Greek philosophy.
Click to expand...
"Truth does not become more true by virtue of the fact that the entire world agrees with it, nor less so even if the whole world disagrees with it." - Moreh Nevuchim 2:15

Not exactly pro-Greek, and not pro-philosophy per se - he accepted some parts of teachings of certain Greek philosophers, but there was a larger issue he attempted to address, reason and faith.

Imagine a person who studies religion and Aristotle, and the question is - what to believe? how to reconcile? That is especially a difficult question for those who are less educated in any of those.

Rambam actually starts with "method". The idea is that reasoned inquiry doesn't contradict religion and it is at the centre of any study.

If you wish, https://www.sefaria.org/Guide_for_the_Perplexed?lang=en
 
Mark Scott Abeln said:
Iliah Borg said:
Mark Scott Abeln said:
Part of the decline of scholarship in that era is undoubtedly due to the Black Death, which may have killed off something like 90% of university faculties.
Click to expand...
Don't forget Hulagu Khan.
Click to expand...
Forget? I never knew about him in the first place.
Click to expand...
"Recently, I’ve been buttonholing everybody I know and telling them about Hulagu." ;)

Loading…

www.newyorker.com

Books from House of Wisdom were used to make causeway to cross the Tigris River. Number of victims depends on whom are you listening to, 90,000 to 2,000,000.
 
bobn2 said:
J A C S said:
MrBrightSide said:
And yet the greatest scientific breakthroughs in the Middle Ages were made by Arab and Persian scholars. Who knows, without the many Islamic innovations in math we might still be painting on cave walls with ox blood instead of taking photos through exquisite optics.
Click to expand...
I do not think that Newton was a Muslim.
Click to expand...
Presumably he also mastered time travel, so that he could do his work in the Middle Ages?
Click to expand...
The time travel back to the Middle Ages was MrBrightSide's accomplishment - a kind of distraction. This would not prevent the esteemed forum members to write dozens of posts about the Middle Ages though.
 
Last edited:
AiryDiscus said:
Member said:
alanr0 wrote: See, for example, the analysis in Jeff Conrad's DoF in Depth...
Click to expand...
I am not ignoring this, but I do not have the time now to read a 45 page PDF on DoF. I skimmed, and have some general objections:
  • This appears to be dominated by geometry. This ignores the wave nature of light and oversimplifies things. He notes that the PSF for a circular aperture of uniform illumination with defocus can be analytically described by a converging series of bessel functions. This is true. Why, then, does he never define his measure of width of this function? 1/e or FWHM, anything conventional is fine, but undefined is not.
  • He shows an equation for the MTF from just defocus, absent of diffraction. This is unphysical and cannot possibly be correct. A quadratic phase error in the pupil does not lead to a special condition of the optical field in the image plane. That is to say the phase does not take on only special values of 0 or pi, and indeed has a continuum of values. This phase conditions stems from interference and cannot be neglected.
  • He has many plots where he shows MTF to be negative. This is by definition incorrect. The real part of the OTF can be negative, the MTF can never be, as it is the modulus of a transfer function.
Click to expand...
If one does not have the time to read a paper one should not waste his/her and everybody's time with flippant objections whose answers are in the paper that one did not read ;-)

PS Speaking of the OP, he seems to have disappeared in a puff of smoke once a figure for CoC came to light.
 
Last edited:
Jack Hogan said:
PS Speaking of the OP, he seems to have disappeared in a puff of smoke once a figure for CoC came to light.
Click to expand...
I'm still here. But you guys got me thinking about the false dichotomy between science and religion that has been created, fostered, and supported by an unholy alliance of money-grubbing ministers and their equally greedy counterparts in the science community.

The two sides find it very profitable to stage fierce but utterly fraudulent mock combats; they get free publicity and use their TV appearances to promote their books, videos, and lectures.

It's all very cynical and irks me no end because they have suckered the general public in a way that is detrimental to both religion and science.

Besides, the Bible is nothing if not a scientific document. It is full of injunctions against witchcraft, astrology, f-stop equivalence, spirit mediums, and all the other crooks, con artists, and crackpots who continue to plague us today.

Jesus himself, it can be argued, was a divine mathematician who took the messy base 10 arithmetic of the Old Testament and recalculated it using his own elegant binary moral calculus. Water into wine, raising the dead, those aren't miracles, they're empirical evidence.

And let us not forget He also invented the IF…THEN statement…

IF meek THEN inherit earth.

Martin Luther? He was the Trump of his day, just another schemer playing to his base; his genius was in contriving excuses that allowed his followers to ignore their obligation to live up to the very moderate standards of conduct that Jesus had laid out in his Powerpoint on the Mount.
 
Jack Hogan said:
AiryDiscus said:
Jack Hogan said:
alanr0 wrote: See, for example, the analysis in Jeff Conrad's DoF in Depth...
Click to expand...
I am not ignoring this, but I do not have the time now to read a 45 page PDF on DoF. I skimmed, and have some general objections:
  • This appears to be dominated by geometry. This ignores the wave nature of light and oversimplifies things. He notes that the PSF for a circular aperture of uniform illumination with defocus can be analytically described by a converging series of bessel functions. This is true. Why, then, does he never define his measure of width of this function? 1/e or FWHM, anything conventional is fine, but undefined is not.
  • He shows an equation for the MTF from just defocus, absent of diffraction. This is unphysical and cannot possibly be correct. A quadratic phase error in the pupil does not lead to a special condition of the optical field in the image plane. That is to say the phase does not take on only special values of 0 or pi, and indeed has a continuum of values. This phase conditions stems from interference and cannot be neglected.
  • He has many plots where he shows MTF to be negative. This is by definition incorrect. The real part of the OTF can be negative, the MTF can never be, as it is the modulus of a transfer function.
Click to expand...
If one does not have the time to read a paper one should not waste his/her and everybody's time with flippant objections whose answers are in the paper that one did not read ;-)

PS Speaking of the OP, he seems to have disappeared in a puff of smoke once a figure for CoC came to light.
Click to expand...
Well, the author is bluntly wrong (e.g. negative MTF). There really is no correct answer to justify this in the text, as no correct answer exists.
 
MrBrightSide said:
Jack Hogan said:
PS Speaking of the OP, he seems to have disappeared in a puff of smoke once a figure for CoC came to light.
Click to expand...
I'm still here. But you guys got me thinking about the false dichotomy between science and religion that has been created, fostered, and supported by an unholy alliance of money-grubbing ministers and their equally greedy counterparts in the science community.

The two sides find it very profitable to stage fierce but utterly fraudulent mock combats; they get free publicity and use their TV appearances to promote their books, videos, and lectures.

It's all very cynical and irks me no end because they have suckered the general public in a way that is detrimental to both religion and science.

Besides, the Bible is nothing if not a scientific document. It is full of injunctions against witchcraft, astrology, f-stop equivalence, spirit mediums, and all the other crooks, con artists, and crackpots who continue to plague us today.

Jesus himself, it can be argued, was a divine mathematician who took the messy base 10 arithmetic of the Old Testament and recalculated it using his own elegant binary moral calculus. Water into wine, raising the dead, those aren't miracles, they're empirical evidence.

And let us not forget He also invented the IF…THEN statement…

IF meek THEN inherit earth.

Martin Luther? He was the Trump of his day, just another schemer playing to his base; his genius was in contriving excuses that allowed his followers to ignore their obligation to live up to the very moderate standards of conduct that Jesus had laid out in his Powerpoint on the Mount.
Click to expand...
Are you OK?
 
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