I think those curves are normalised. It's hard to see any way the top layer can capture fewer long wavelength photons than the bottom layer.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
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Will sigma release a new camera this year?
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They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
Sorry.
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Ted
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rick decker
Forum Pro
do you have a link to his statement?
Thanks
Rick
Thanks
Rick
docmaas
Veteran Member
sort of.... SDQ batteries in a pentax K-1 do not allow the battery door to close and the chargers are not compatible as far as fitting the batteries. IIRC Pentax batteries fit the SDQ fine though.
Mike
"For me, photography is only an artistic language. The camera is my pencil. -- Charly Ho
"At every crossroads on the path that leads to the future, tradition has placed 10,000 men to guard the past."
Maurice Maeterlinck
Mike
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"For me, photography is only an artistic language. The camera is my pencil. -- Charly Ho
"At every crossroads on the path that leads to the future, tradition has placed 10,000 men to guard the past."
Maurice Maeterlinck
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On a similar basis, Mike, I've had batteries that would not allow the SD1M door to close fully but fit the SD14 perfectly well. A slot in the side of the battery needed a bit of "Dremeling" ...
If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
Lukacs85
Leading Member
I hope not. We have everything, old dp and sd series, Merrills with extraordinary micro contrast, compact and interchangeable lens quattros with exceptional low iso IQ. Only a 35mm sensor sd quattro missing from table, it would be wise for sigma's FF art lens lineup, also makes joke about sdq-h. MF would cost a fortune with proper lens lineup, there is no way that sigma invest such development.
However there is always a space for improvement, like better noise handling, faster AF. I don't expect higher resolution.
Sigma should take time developing a really advenced sensor, and make a small aps-c dp quattro like camera with high quality interchangeable, small lenses with f2.8 speed, and a sd quattro like FF body for art lenses.
However there is always a space for improvement, like better noise handling, faster AF. I don't expect higher resolution.
Sigma should take time developing a really advenced sensor, and make a small aps-c dp quattro like camera with high quality interchangeable, small lenses with f2.8 speed, and a sd quattro like FF body for art lenses.
docmaas
Veteran Member
Me too. I thought about doing it for the K-1 but it was too much trouble so I returned the camera. ;<)
Mike
Mike
I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
--
Ted
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Very interesting stuff Ted. Thanks!I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
--
Ted
--
Scott Barton Kennelly
I agree with what you've said here . . . except the DP Quattro with the interchangeable lenses doesn't make sense to me. If it's a DP it doesn't have interchangeable lenses. If it has interchangeable lenses it is an SD. I think maybe what you really want is a really small version of the SD and a set of f2.8 Art lenses? (presumably because this would make for a very carryable and versatile camera system) Are you suggesting a shorter flange distance camera, similar to a Sony A6000? . . . or are you talking about something even smaller, like a Sony A5000, which has no viewfinder?
Loading…
www.dpreview.com
If they made something like that, which they could ship with an adapter to mount all their current SA mount lenses, I would be behind the development of that. They could use the same sensor in future SD models, and the lenses could be made in a way that they could be used on the Sony mirrorless cameas, m4/3, and various other cameras. In fact, they already have a range of lenses like that in Sony E mount, so they could just make a mount and use those lenses to start with. Such a camera would help give them an excuse to develop a range of Art lenses for the Sony E mount, possibly the Fuji mirrorless APS-C cameras, Canon's new mirrorless cameras, and m4/3 cameras.
Lukacs85
Leading Member
In size of DP compacts a mirroless APS-C camera, and compatible with DN lens series: https://www.sigmaphoto.com/lenses/dn-for-mirrorless
Of course with converter you can use any other non-mirrorless lenses.
Of course with converter you can use any other non-mirrorless lenses.
I don‘t understand why you are so adamant about „capture“ or „merge“ being totally different from „absorb“.I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
LOLI don‘t understand why you are so adamant about „capture“ or „merge“ being totally different from „absorb“.I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
Ted is very pedantic sometimes.
--
Scott Barton Kennelly
Of course the text is correct, but it only says in more words that the electrons capture the photons.I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
After all, one could quibble about "the electrons become excited", but we have to use metaphors to talk about these things. One could quibble about "by thermal energy" -- what particles carry the "thermal energy" ?
One could quibble about "the electrons are free to conduct current" -- they don't conduct the current, they are the current.
+++++++++++++++
The real point of interest is why the longer wavelength photons penetrate deeper into the silicon than the short wavelength photons.
D Cox said:I don‘t understand why you are so adamant about „capture“ or „merge“ being totally different from „absorb“.I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
"It's hard to see any way the top layer can capture fewer long wavelength photons than the bottom layer."
Now, according to Frank, „capture“ or „merge“ or „absorb“ all mean about the same thing.
So, D Cox thinks that the top layer captures MORE long wavelength photons than the bottom layer. Anyone else here think that? That's how his sentence reads, whether he meant it or not, and it remains nonsense in my humble view.
--
Ted
Last edited:
Everyone and his dog knows why the longer wavelength photons penetrate deeper into the silicon than the short wavelength photons. You apparently did not - because your earlier sentence states exactly the opposite:Of course the text is correct, but it only says in more words that the electrons capture the photons.I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
After all, one could quibble about "the electrons become excited", but we have to use metaphors to talk about these things. One could quibble about "by thermal energy" -- what particles carry the "thermal energy" ?
One could quibble about "the electrons are free to conduct current" -- they don't conduct the current, they are the current.
+++++++++++++++
The real point of interest is why the longer wavelength photons penetrate deeper into the silicon than the short wavelength photons.
You said "It's hard to see any way the top layer can capture fewer long wavelength photons than the bottom layer". That means you think that the top layer must capture more long wavelength photons than the bottom layer; Is that what you really think?!!. There must be a typo; your English is plain enough.
--
Ted
Last edited:
snip...
1. The word capture is not mis-used but describes the effect quite good. It doesn't make non-sense out of his sentence.
2. In fact, it is even true in some sense. The absorbtion rate of photons of a given wavelength is the same regardless of the depth. Therefore, for identical thickness of the absorbtion area, the top layer absorbs more long wavelength photons than the bottom layer. In fact, it absorbs more photons of any wavelength (in the optical range) than any lower laying layers of identical thickness. The Foveon design makes up for that by increasing the thickness of the layers from top to bottom. The different color response of the layers comes from the fact that short wavelengths have a higher absorbtion rate. Therefore, the color balance shifts from more blue to more red from top to bottom.
3. My question was why you think that "capture", "merge" and "absorb" are that different. You turn it into: I said that they all mean the same thing.
4. And this is now pretty pedantic from my side. D Cox says that he doesn't understand why the top layer capture fewer long wavelength photons. He does not say that it capture more of them.
For a pedant, you treat logic a bit careless.
1. The word capture is not mis-used but describes the effect quite good. It doesn't make non-sense out of his sentence.
2. In fact, it is even true in some sense. The absorbtion rate of photons of a given wavelength is the same regardless of the depth. Therefore, for identical thickness of the absorbtion area, the top layer absorbs more long wavelength photons than the bottom layer. In fact, it absorbs more photons of any wavelength (in the optical range) than any lower laying layers of identical thickness. The Foveon design makes up for that by increasing the thickness of the layers from top to bottom. The different color response of the layers comes from the fact that short wavelengths have a higher absorbtion rate. Therefore, the color balance shifts from more blue to more red from top to bottom.
3. My question was why you think that "capture", "merge" and "absorb" are that different. You turn it into: I said that they all mean the same thing.
4. And this is now pretty pedantic from my side. D Cox says that he doesn't understand why the top layer capture fewer long wavelength photons. He does not say that it capture more of them.
Because the absorption rate of photons in silicon depends on the wavelength. The longer the wavelength, the lower the absorption rate. Therefore, in lower layers, you have more red photons which "survived" the passage through the upper layers than blue ones which have already been absorbed mostly by the upper layers.Of course the text is correct, but it only says in more words that the electrons capture the photons.I give up, Don. Your continued use of alternative terminology is not helping us at all. Photons do not "merge" with electrons. Here's what happens:If a photon merges with an electron, increasing its energy level, I would say that the electron has captured the photon. What word would you use ?They are not.I think those curves are normalised.Instead of words like "get" and "guess" here's a rather more precise view of a Foveon wavelength response:
Top graph is bare sensor without a UV/IR blocking filter
Pardon my pedantry ...
These are normalized:
See how the top layer peaks at 1.00 ... an impossible value for a photodiode.
The word "capture" has been mis-used, making nonsense of the entire sentence.
" Silicon is a semiconductor with a band gap energy of 1.12 eV at room temperature. This is the gap between the valence band and the conduction band. At absolute zero temperature the valence band is completely filled and the conduction band is vacant. As the temperature increases, the electrons become excited and escalate from the valence
band to the conduction band by thermal energy. The electrons can also be escalated to the conduction band by particles or photons with energies greater than 1.12eV, which corresponds to wavelengths shorter than 1100 nm. The resulting electrons in the conduction band are free to conduct current.
www.osioptoelectronics.com/application-notes/an-photodiode-parameters-characteristics.pdf
If we can agree on the quoted text, we're done.
After all, one could quibble about "the electrons become excited", but we have to use metaphors to talk about these things. One could quibble about "by thermal energy" -- what particles carry the "thermal energy" ?
One could quibble about "the electrons are free to conduct current" -- they don't conduct the current, they are the current.
+++++++++++++++
The real point of interest is why the longer wavelength photons penetrate deeper into the silicon than the short wavelength photons.
OUCH!
"The effect" being what, exactly?
Got a credible link for that?
This help?
Observe that the absorption per unit depth does appear to vary with depth, i.e. is not the same regardless of depth ...
Yes, later I edited it to "about the same thing".
A reasonable point.
--
Ted
Last edited:
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