A7R6 and diffraction
p.3 #1A7R6 and diffraction
Jack Flesher wrote:
---------------------------------------------
"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"You guys are both right. My question was perhaps poorly worded, or not adequately worded. I am interested in finding the optimal balance point; where the negative effects of diffraction from stopping down begin to negate the resulting DoF resolution gains made from that same stopping down.
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.Jack, I don’t think there is a single, unified answer to this, as in “f/11 is that aperture.”
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.I hear you Dan, and I accept my above curve intersection thoughts coupled with a given lens’ optimal resolution aperture curve overlaying on that same graph, the situational image setup may allow for a broader or tighter aperture range inside the resulting trisectional overlap zone.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the...Show more →
The blessing and curse of high-resolution sensors
You might also want to look into deconvolution workflows to see how much acuity can be restored in post. I haven't played with that myself.
gdanmitchell wrote
Jack Flesher wrote
aCuria wrote
No, the thread is about sharpness maximization, stopping down some reduces aberrations and increases sharpness. Jack is asking exactly how much to stop down, its a reasonable question.snapsy wrote
Jack's first sentence in his OP:"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the...Show more →
The blessing and curse of high-resolution sensors
You might also want to look into deconvolution workflows to see how much acuity can be restored in post. I haven't played with that myself.Aug 20, 2026 at 08:31 AM
p.3 #2A7R6 and diffraction
snapsy wrote:
---------------------------------------------
"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"You guys are both right. My question was perhaps poorly worded, or not adequately worded. I am interested in finding the optimal balance point; where the negative effects of diffraction from stopping down begin to negate the resulting DoF resolution gains made from that same stopping down.
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.Jack, I don’t think there is a single, unified answer to this, as in “f/11 is that aperture.”
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.I hear you Dan, and I accept my above curve intersection thoughts coupled with a given lens’ optimal resolution aperture curve overlaying on that same graph, the situational image setup may allow for a broader or tighter aperture range inside the resulting trisectional overlap zone.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the deeper dive query.
Or perhaps good enough is, and I’m tilting at windmills…The blessing and curse of high-resolution sensors You might also want to look into deconvolution workflows to see how much acuity can be restored in post. I haven't played with that myself.
I’ve only lightly delved into that. My initial findings are that raw sharpening is no longer the savior it used to be, hence my comment above about sharpening adjustment tweaks being almost irrelevant. Even with ACR’s newly added AI “Raw Details” sharpening, it’s impact has been irrelevant or in many cases actually worsening the micro details.
In that same vein and perhaps ironically, the surprising revelation is that utilizing ACR’s AI “Super Resolution.” This action quadruples your image size and the resulting resolution and detail is frankly remarkable considering the 4x resolution gained. For me it seemingly renders pixel-shift irrelevant. The fact that it works so well adds to me believing the base files are pretty close to ideal after deconvolution.
PS: with the A7R6 and my sharpest lenses, my current ACR sharpening is radius 0.6, amount 50, details 25. At this setting, haloing at the highest frequency details are prevented. Bump amount or radius up and they start creeping in. Finally, adding in a bit of clarity and structure usually enhances the sharpening appearance a bit.
Edited on Aug 20, 2026 at 09:11 AM · View previous versions
Jack Flesher wrote
gdanmitchell wrote
Jack Flesher wrote
aCuria wrote
No, the thread is about sharpness maximization, stopping down some reduces aberrations and increases sharpness. Jack is asking exactly how much to stop down, its a reasonable question.snapsy wrote
Jack's first sentence in his OP:"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the deeper dive query.
Or perhaps good enough is, and I’m tilting at windmills…
You might also want to look into deconvolution workflows to see how much acuity can be restored in post. I haven't played with that myself.I’ve only lightly delved into that. My initial findings are that raw sharpening is no longer the savior it used to be, hence my comment above about sharpening adjustment tweaks being almost irrelevant. Even with ACR’s newly added AI “Raw Details” sharpening, it’s impact has been irrelevant or in many cases actually worsening the micro details.
In that same vein and perhaps ironically, the surprising revelation is that utilizing ACR’s AI “Super Resolution.” This action quadruples your image size and the resulting resolution and detail is frankly remarkable considering the 4x resolution gained. For me it seemingly renders pixel-shift irrelevant. The fact that it works so well adds to me believing the base files are pretty close to ideal after deconvolution.
PS: with the A7R6 and my sharpest lenses, my current ACR sharpening is radius 0.6, amount 50, details 25. At this setting, haloing at the highest frequency details are prevented. Bump amount or radius up and they start creeping in. Finally, adding in a bit of clarity and structure usually enhances the sharpening appearance a bit.
Edited on Aug 20, 2026 at 09:11 AM · View previous versions
Aug 20, 2026 at 09:05 AM
p.3 #3A7R6 and diffraction
Jack Flesher wrote:
---------------------------------------------
"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"You guys are both right. My question was perhaps poorly worded, or not adequately worded. I am interested in finding the optimal balance point; where the negative effects of diffraction from stopping down begin to negate the resulting DoF resolution gains made from that same stopping down.
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.Jack, I don’t think there is a single, unified answer to this, as in “f/11 is that aperture.”
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.I hear you Dan, and I accept my above curve intersection thoughts coupled with a given lens’ optimal resolution aperture curve overlaying on that same graph, the situational image setup may allow for a broader or tighter aperture range inside the resulting trisectional overlap zone.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the...Show more →
The good news — often misunderstood — is that there is no increase in diffraction blur with the higher res sensor. The amount of diffraction at a given aperture, expressed as a fraction of image width, if you will, is exactly the same whether you use a 8MP FF camera or a 66Mp FF camera. In other words, if you make two otherwise identical images (same lens, same aperture, etc.) on two such cameras and make two prints at the same size… they each have the exact same amount of diffraction blur.
It only seems like there’s “more diffraction blur” because when we look at, say, a 1000 x 1000 bit of an image from the higher resolution system we are simply looking at the same amount of blur but magnified more.
More good news: In some situations you can obtain some advantage from the higher resolution sensor and a slightlyl larger aperture and take advantage of lower diffraction at those apertures. Of course, gaining that extra little bit of potential sharpness has (as all things do) its own set of minuses. For example, you’ll get a smaller DOF. Unless you use really good lenses, it is possible (though not certain) that you could have some corner issues.
So it is a balancing act, isn’t it? If you need the extra DOF you can use he same apertures that you’d choose with a 30MP or 16MP FF camera and you won’t lose anything — you’ll still get an image that is at least as sharp as what you got with an older, lower res camera. If sharpness trumps that DOF increase you’ll choose the larger aperture and live with it or possibly resort of focus stacking or a TS lens instead.
gdanmitchell wrote
Jack Flesher wrote
aCuria wrote
No, the thread is about sharpness maximization, stopping down some reduces aberrations and increases sharpness. Jack is asking exactly how much to stop down, its a reasonable question.snapsy wrote
Jack's first sentence in his OP:"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the...Show more →
The good news — often misunderstood — is that there is no increase in diffraction blur with the higher res sensor. The amount of diffraction at a given aperture, expressed as a fraction of image width, if you will, is exactly the same whether you use a 8MP FF camera or a 66Mp FF camera. In other words, if you make two otherwise identical images (same lens, same aperture, etc.) on two such cameras and make two prints at the same size… they each have the exact same amount of diffraction blur.
It only seems like there’s “more diffraction blur” because when we look at, say, a 1000 x 1000 bit of an image from the higher resolution system we are simply looking at the same amount of blur but magnified more.
More good news: In some situations you can obtain some advantage from the higher resolution sensor and a slightlyl larger aperture and take advantage of lower diffraction at those apertures. Of course, gaining that extra little bit of potential sharpness has (as all things do) its own set of minuses. For example, you’ll get a smaller DOF. Unless you use really good lenses, it is possible (though not certain) that you could have some corner issues.
So it is a balancing act, isn’t it? If you need the extra DOF you can use he same apertures that you’d choose with a 30MP or 16MP FF camera and you won’t lose anything — you’ll still get an image that is at least as sharp as what you got with an older, lower res camera. If sharpness trumps that DOF increase you’ll choose the larger aperture and live with it or possibly resort of focus stacking or a TS lens instead.
Aug 20, 2026 at 09:09 AM
p.3 #4A7R6 and diffraction
I'd second the idea of looking at deconvolution sharpening. Diffraction is different from other things that soften an image in that it is exactly calculable based on the f number. Its not like an aberration, which varies from one lens to another. So sharpening algorithms can do more to correct diffraction than other things. If you have Lightroom that is controlled by the Detail slider. The higher it is the more deconvolution sharpening you are using.
But I'd also say that looking at all your images at 100% on the screen is maybe sending you down a rabbit hole that is not worthwhile. I think the advent of pixel peeping has made us all much more sensitive to pixel level image qualities rather than whole image qualities. But I think for a viewer things like contrast, which is a lower resolution sharpness, and the relative sharpness of various element in the scene is more important. That's why getting uniform image sharpness through the depth of an image may be more important than optimizing sharpness at 100%.
Sure, in some cases you really need the pixel level sharpness, and in that case you need to focus stack. But I will note that many landscape photographers whose work I admire frequently are creating images at f/16.
Finally, no matter whether you want pixel level sharpness or not, there really can't be an optimal f/number balancing DOF and diffraction because every scene has a different depth and a different set of subject distances. For a relatively flat scene, you surely want something like f/5.6, but for a near to far landscape that aperture won't work without focus stacking.
-Will
But I'd also say that looking at all your images at 100% on the screen is maybe sending you down a rabbit hole that is not worthwhile. I think the advent of pixel peeping has made us all much more sensitive to pixel level image qualities rather than whole image qualities. But I think for a viewer things like contrast, which is a lower resolution sharpness, and the relative sharpness of various element in the scene is more important. That's why getting uniform image sharpness through the depth of an image may be more important than optimizing sharpness at 100%.
Sure, in some cases you really need the pixel level sharpness, and in that case you need to focus stack. But I will note that many landscape photographers whose work I admire frequently are creating images at f/16.
Finally, no matter whether you want pixel level sharpness or not, there really can't be an optimal f/number balancing DOF and diffraction because every scene has a different depth and a different set of subject distances. For a relatively flat scene, you surely want something like f/5.6, but for a near to far landscape that aperture won't work without focus stacking.
-Will
Aug 20, 2026 at 09:14 AM
p.3 #5A7R6 and diffraction
gdanmitchell wrote:
---------------------------------------------
"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"You guys are both right. My question was perhaps poorly worded, or not adequately worded. I am interested in finding the optimal balance point; where the negative effects of diffraction from stopping down begin to negate the resulting DoF resolution gains made from that same stopping down.
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.Jack, I don’t think there is a single, unified answer to this, as in “f/11 is that aperture.”
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.I hear you Dan, and I accept my above curve intersection thoughts coupled with a given lens’ optimal resolution aperture curve overlaying on that same graph, the situational image setup may allow for a broader or tighter aperture range inside the resulting trisectional overlap zone.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the deeper dive query.
Or perhaps good enough is, and I’m tilting at windmills…The good news — often misunderstood — is that there is no increase in diffraction blur with the higher res sensor. The amount of diffraction at a given aperture, expressed as a fraction of image width, if you will, is exactly the same whether you use a 8MP FF camera or a 66Mp FF camera. In other words, if you make two otherwise identical images (same lens, same aperture, etc.) on two such cameras and make two prints at the same size… they each have the exact same amount of diffraction blur.
It only seems like there’s “more diffraction blur” because when...Show more →
Yes but. The fact remains it is more visible. You will understand my conundrum when you get these files in front of you. Add to this a few new workflow options AI is allowing. One example I’ve been experimenting with that may interest you, is a bastardized fractal print sharpening process utilizing ACR’s “Super Resolution” along with PS’s intelligent “sharper” down-sizing protocol — the resulting print file is compelling. A small gain in most cases, but compelling.
I realize I am veering OT, and apologies. But this is somewhat relevant to the discussion I think. Here is an image I captured hand-held with the Sony 20-70 at 20mm and f8. I think it sort of underscores the above. This lens at 20mm is not at it's best and f8 appears to work well, and I am reasonably confident the plane is in the acceptable DoF. I used the fractal sharpening mentioned to enhance the micro-detail on the plane -- it definitely showed a bit of diffraction degrading. These are both sized to 2048 px wide before the frame so view them appropriately.
First is the full image for reference. Next is the as-shot plane resolution, processed raw with as close to the ideal sharpening settings as I have found with the tools I have. Final is the Super Res>partial downsampled final, which I feel shows a slight increase in rendering. This final full size image was 13378 px wide which would render a 45" wide print at 300ppi while the native file would be 33" wide at 300ppi for reference.
My conclusion is I need to resort to further empirical testing. In this case I have confirmed f8 is fine to use and can probably get to f9 without much additional loss. I will experiment when next out using f11 at various focal lengths to see how they react, but I remain dubious
As shot, no upscale>reduction
After upscale>reduction
Jack Flesher wrote
gdanmitchell wrote
Jack Flesher wrote
aCuria wrote
No, the thread is about sharpness maximization, stopping down some reduces aberrations and increases sharpness. Jack is asking exactly how much to stop down, its a reasonable question.snapsy wrote
Jack's first sentence in his OP:"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the deeper dive query.
Or perhaps good enough is, and I’m tilting at windmills…
It only seems like there’s “more diffraction blur” because when...Show more →
Yes but. The fact remains it is more visible. You will understand my conundrum when you get these files in front of you. Add to this a few new workflow options AI is allowing. One example I’ve been experimenting with that may interest you, is a bastardized fractal print sharpening process utilizing ACR’s “Super Resolution” along with PS’s intelligent “sharper” down-sizing protocol — the resulting print file is compelling. A small gain in most cases, but compelling.
I realize I am veering OT, and apologies. But this is somewhat relevant to the discussion I think. Here is an image I captured hand-held with the Sony 20-70 at 20mm and f8. I think it sort of underscores the above. This lens at 20mm is not at it's best and f8 appears to work well, and I am reasonably confident the plane is in the acceptable DoF. I used the fractal sharpening mentioned to enhance the micro-detail on the plane -- it definitely showed a bit of diffraction degrading. These are both sized to 2048 px wide before the frame so view them appropriately.
First is the full image for reference. Next is the as-shot plane resolution, processed raw with as close to the ideal sharpening settings as I have found with the tools I have. Final is the Super Res>partial downsampled final, which I feel shows a slight increase in rendering. This final full size image was 13378 px wide which would render a 45" wide print at 300ppi while the native file would be 33" wide at 300ppi for reference.
My conclusion is I need to resort to further empirical testing. In this case I have confirmed f8 is fine to use and can probably get to f9 without much additional loss. I will experiment when next out using f11 at various focal lengths to see how they react, but I remain dubious
ILCE-7RM6 FE 20-70mm F4 G lens 20mm f/8.0 1/400s 100 ISO 0.0 EV
As shot, no upscale>reduction
After upscale>reduction
Aug 20, 2026 at 09:17 AM
p.3 #6A7R6 and diffraction
WillR wrote:
But I'd also say that looking at all your images at 100% on the screen is maybe sending you down a rabbit hole that is not worthwhile. I think the advent of pixel peeping has made us all much more sensitive to pixel level image qualities rather than whole image qualities. But I think for a viewer things like contrast, which is a lower resolution sharpness, and the relative sharpness of various element in the scene is more important. That's why getting uniform image sharpness through the depth of an image may be more important than optimizing sharpness at 100%....Show more →
Amen. You get it! :-)
But I'd also say that looking at all your images at 100% on the screen is maybe sending you down a rabbit hole that is not worthwhile. I think the advent of pixel peeping has made us all much more sensitive to pixel level image qualities rather than whole image qualities. But I think for a viewer things like contrast, which is a lower resolution sharpness, and the relative sharpness of various element in the scene is more important. That's why getting uniform image sharpness through the depth of an image may be more important than optimizing sharpness at 100%....Show more →
Amen. You get it! :-)
Aug 20, 2026 at 12:47 PM
p.3 #7A7R6 and diffraction
I also agree. As with a lot of dogmatic statements about this versus that in photography, most are not terribly relevant. Along with many others I am occasionally guilty of the "sharpness at all costs" approach. I focus stack way too much. As I've matured, I'm now officially "elderly," I've realized that the overall quality of the image is what matters, not so much the technical aspects.
Others have said more eloquently that the equipment used by many of the 20th century's most famous photographers (Adams, Weston, Cartier-Bresson and many others) would not even be considered by today's pixel-peeping fanatics.
I'm not saying sharpness is not important, it is, but focusing (pun intended) on that above all else is foolish. Unless one does side by side comparisons, which most people do not do, these differences pale in comparison to an evaluation of the image as a whole. Sadly, whether it be on a screen or a print, (the only way a photograph is "real" to me) the few seconds most people give to evaluating an image makes such concerns even less relevant.
Others have said more eloquently that the equipment used by many of the 20th century's most famous photographers (Adams, Weston, Cartier-Bresson and many others) would not even be considered by today's pixel-peeping fanatics.
I'm not saying sharpness is not important, it is, but focusing (pun intended) on that above all else is foolish. Unless one does side by side comparisons, which most people do not do, these differences pale in comparison to an evaluation of the image as a whole. Sadly, whether it be on a screen or a print, (the only way a photograph is "real" to me) the few seconds most people give to evaluating an image makes such concerns even less relevant.
Aug 20, 2026 at 01:16 PM
p.3 #8A7R6 and diffraction
doc4x5 wrote:
I also agree. As with a lot of dogmatic statements about this versus that in photography, most are not terribly relevant. Along with many others I am occasionally guilty of the "sharpness at all costs" approach. I focus stack way too much. As I've matured, I'm now officially "elderly," I've realized that the overall quality of the image is what matters, not so much the technical aspects.
Others have said more eloquently that the equipment used by many of the 20th century's most famous photographers (Adams, Weston, Cartier-Bresson and many others) would not even be considered by today's pixel-peeping fanatics....Show more →
On a few occasions I have had very strong emotional/esthetic reactions to particular photographs — almost always that I’ve viewed in the form of prints: two exhibits of the huge prints by Jeff Wall (who oddly seems mostly unknown to many photographers), another time to exhibits of some Avedon prints. Once it was a surprising reaction to an Adams image that I had seen many times as a print — it was an image that I viewed in the back of an airlines in-flight magazine where I was struck by the stark difference between that very “quiet” image and the situation I was currently experiencing.
In no case, these or others, have I ever been moved by the sharpness of a print.
I have been moved by many prints that were not sharp at the level we are postulating about here.
I also agree. As with a lot of dogmatic statements about this versus that in photography, most are not terribly relevant. Along with many others I am occasionally guilty of the "sharpness at all costs" approach. I focus stack way too much. As I've matured, I'm now officially "elderly," I've realized that the overall quality of the image is what matters, not so much the technical aspects.
Others have said more eloquently that the equipment used by many of the 20th century's most famous photographers (Adams, Weston, Cartier-Bresson and many others) would not even be considered by today's pixel-peeping fanatics....Show more →
On a few occasions I have had very strong emotional/esthetic reactions to particular photographs — almost always that I’ve viewed in the form of prints: two exhibits of the huge prints by Jeff Wall (who oddly seems mostly unknown to many photographers), another time to exhibits of some Avedon prints. Once it was a surprising reaction to an Adams image that I had seen many times as a print — it was an image that I viewed in the back of an airlines in-flight magazine where I was struck by the stark difference between that very “quiet” image and the situation I was currently experiencing.
In no case, these or others, have I ever been moved by the sharpness of a print.
I have been moved by many prints that were not sharp at the level we are postulating about here.
Aug 20, 2026 at 01:32 PM
p.3 #9A7R6 and diffraction
The 20-70/4 is not the sharpest tool in the shed and has mandatory computational correction for severe distortion at the wider focal lengths. You may indeed need f/8 to optimize results although suffering from some diffarction.
EBH
EBH
Aug 20, 2026 at 01:59 PM
p.3 #10A7R6 and diffraction
Jack Flesher wrote:
---------------------------------------------
"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"You guys are both right. My question was perhaps poorly worded, or not adequately worded. I am interested in finding the optimal balance point; where the negative effects of diffraction from stopping down begin to negate the resulting DoF resolution gains made from that same stopping down.
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others...Show more →
For an ideal lens the intersection is when the airy disk diameter = 2 pixels, but this varies with the wavelength (color of the subject).
aCuria wrote
No, the thread is about sharpness maximization, stopping down some reduces aberrations and increases sharpness. Jack is asking exactly how much to stop down, its a reasonable question.snapsy wrote
Jack's first sentence in his OP:"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others...Show more →
For an ideal lens the intersection is when the airy disk diameter = 2 pixels, but this varies with the wavelength (color of the subject).
Aug 20, 2026 at 06:09 PM
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p.3 #11A7R6 and diffraction
gdanmitchell wrote:
---------------------------------------------
"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"You guys are both right. My question was perhaps poorly worded, or not adequately worded. I am interested in finding the optimal balance point; where the negative effects of diffraction from stopping down begin to negate the resulting DoF resolution gains made from that same stopping down.
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.Jack, I don’t think there is a single, unified answer to this, as in “f/11 is that aperture.”
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.I hear you Dan, and I accept my above curve intersection thoughts coupled with a given lens’ optimal resolution aperture curve overlaying on that same graph, the situational image setup may allow for a broader or tighter aperture range inside the resulting trisectional overlap zone.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the deeper dive query.
Or perhaps good enough is, and I’m tilting at windmills…The good news — often misunderstood — is that there is no increase in diffraction blur with the higher res sensor. The amount of diffraction at a given aperture, expressed as a fraction of image width, if you will, is exactly the same whether you use a 8MP FF camera or a 66Mp FF camera. In other words, if you make two otherwise identical images (same lens, same aperture, etc.) on two such cameras and make two prints at the same size… they each have the exact same amount of diffraction blur.
It only seems like there’s “more diffraction blur” because when...Show more →
I agree with Dan. Not only "there is no increase in diffraction blur with the higher res sensor", also diffraction is part of the photographic equivalence (as I already mentioned above); thus, the diffraction-limited apertures scale with the crop factor between system that have sensors of different sizes.
I am also with Bill Claff who noted that "photosite size is not a factor in noise or diffraction as it applies to our photography" and "It does not matter whether the Airy disc is larger than an individual photosite. What matters is whether the Airy disc is larger than the group of photosites that comprise the COC" (COC = circle of confusion).
For details, see
https://www.photonstophotos.net/GeneralTopics/Sensors_&_Raw/Circle_of_Confusion.htm
https://www.photonstophotos.net/GeneralTopics/Sensors_&_Raw/Resolution_Doesn't_Matter.htm
The practical point here is that the smallest discernible by human eye element (point) of a printed image, or one that is presented on a display (at typical viewing distances and typical print/display sizes), is comprised of a group of pixels. These pixels are binned. Increasing the resolution by increasing the number of photo sites means that more of these are binned - there is no increased diffraction visible to the viewers. While viewing images at 100% is useful to verify whether an image is in focus and was not adversely affected my motion blur, this practice can be misleading when used to decide whether the image is acceptably sharp. An image is acceptably sharp when it looks sharp when viewed as a whole (e.g., as a print), from a reasonable and meaningful viewing distance. Thus, while the onset of diffraction is seen at f/8 on a full-frame system upon pixel-peeping, it is reasonable to expect that softening due to diffraction would not be seen when viewing the same image as a print or on a display even if the aperture had been further closed to f/11.
Jack Flesher wrote
gdanmitchell wrote
Jack Flesher wrote
aCuria wrote
No, the thread is about sharpness maximization, stopping down some reduces aberrations and increases sharpness. Jack is asking exactly how much to stop down, its a reasonable question.snapsy wrote
Jack's first sentence in his OP:"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the deeper dive query.
Or perhaps good enough is, and I’m tilting at windmills…
It only seems like there’s “more diffraction blur” because when...Show more →
I agree with Dan. Not only "there is no increase in diffraction blur with the higher res sensor", also diffraction is part of the photographic equivalence (as I already mentioned above); thus, the diffraction-limited apertures scale with the crop factor between system that have sensors of different sizes.
I am also with Bill Claff who noted that "photosite size is not a factor in noise or diffraction as it applies to our photography" and "It does not matter whether the Airy disc is larger than an individual photosite. What matters is whether the Airy disc is larger than the group of photosites that comprise the COC" (COC = circle of confusion).
For details, see
https://www.photonstophotos.net/GeneralTopics/Sensors_&_Raw/Circle_of_Confusion.htm
https://www.photonstophotos.net/GeneralTopics/Sensors_&_Raw/Resolution_Doesn't_Matter.htm
The practical point here is that the smallest discernible by human eye element (point) of a printed image, or one that is presented on a display (at typical viewing distances and typical print/display sizes), is comprised of a group of pixels. These pixels are binned. Increasing the resolution by increasing the number of photo sites means that more of these are binned - there is no increased diffraction visible to the viewers. While viewing images at 100% is useful to verify whether an image is in focus and was not adversely affected my motion blur, this practice can be misleading when used to decide whether the image is acceptably sharp. An image is acceptably sharp when it looks sharp when viewed as a whole (e.g., as a print), from a reasonable and meaningful viewing distance. Thus, while the onset of diffraction is seen at f/8 on a full-frame system upon pixel-peeping, it is reasonable to expect that softening due to diffraction would not be seen when viewing the same image as a print or on a display even if the aperture had been further closed to f/11.
Aug 20, 2026 at 07:38 PM
p.3 #12A7R6 and diffraction
ruthenium wrote:
The practical point here is that the smallest discernible by human eye element (point) of a printed image, or one that is presented on a display (at typical viewing distances and typical print/display sizes), is comprised of a group of pixels. These pixels are binned. Increasing the resolution by increasing the number of photo sites means that more of these are binned - there is no increased diffraction visible to the viewers. While viewing images at 100% is useful to verify whether an image is in focus and was not adversely affected my motion blur, this practice can be misleading...Show more →
With standards that low, why bother with a 67MP camera at all? 33MP would likely be just fine for them.
Am I the only one that looks at sharpness on the pixel level, not all the time but to establish lenses and settings?
For me an image printed on A4 should look good as much as A0, both viewed at 10-12" away.
EBH
The practical point here is that the smallest discernible by human eye element (point) of a printed image, or one that is presented on a display (at typical viewing distances and typical print/display sizes), is comprised of a group of pixels. These pixels are binned. Increasing the resolution by increasing the number of photo sites means that more of these are binned - there is no increased diffraction visible to the viewers. While viewing images at 100% is useful to verify whether an image is in focus and was not adversely affected my motion blur, this practice can be misleading...Show more →
With standards that low, why bother with a 67MP camera at all? 33MP would likely be just fine for them.
Am I the only one that looks at sharpness on the pixel level, not all the time but to establish lenses and settings?
For me an image printed on A4 should look good as much as A0, both viewed at 10-12" away.
EBH
Aug 20, 2026 at 11:12 PM
p.3 #13A7R6 and diffraction
I'm interested in the 'viewing distance to diagonal' ratio people use for 'enjoyment/assessment viewing' (not necessarily editing), acknowledging the many factors that apply. I much prefer 2x (even for editing) but it appears the 'standards' do not agree with my tastes:
"most industry standards and consumer habits point to a viewing distance to diagonal ratio of about 1.2 to 1.6, which creates a comfortable 30-degree field of view. Older standard-definition rules suggested a much further ratio of 2.5 to 3.0 times the diagonal."
I don't find this close distance 'comfortable' at all. At 1.2 (some suggest 1.05!) you have to keep your eyes busy to see the image in parts, as you cannot view the whole image in one go. Little wonder people mock those who value image dimensionality - they appear to be sitting too close to see the whole image with little eye movement required. The whole is greater than the sum of its parts. I wondered about the relationship between screen viewing distance and myopia. Wonder no more. -->
'Myopia, or nearsightedness, is *increasing rapidly* worldwide, particularly among children and adolescents. Studies indicate that global prevalence has surged over the past few decades, with projections estimating that nearly 50% of the world's population (about 5 billion people) will be myopic by 2050.' cheers.
"most industry standards and consumer habits point to a viewing distance to diagonal ratio of about 1.2 to 1.6, which creates a comfortable 30-degree field of view. Older standard-definition rules suggested a much further ratio of 2.5 to 3.0 times the diagonal."
I don't find this close distance 'comfortable' at all. At 1.2 (some suggest 1.05!) you have to keep your eyes busy to see the image in parts, as you cannot view the whole image in one go. Little wonder people mock those who value image dimensionality - they appear to be sitting too close to see the whole image with little eye movement required. The whole is greater than the sum of its parts. I wondered about the relationship between screen viewing distance and myopia. Wonder no more. -->
'Myopia, or nearsightedness, is *increasing rapidly* worldwide, particularly among children and adolescents. Studies indicate that global prevalence has surged over the past few decades, with projections estimating that nearly 50% of the world's population (about 5 billion people) will be myopic by 2050.' cheers.
Aug 21, 2026 at 12:44 AM
p.3 #14A7R6 and diffraction
EB-1 wrote:
With standards that low, why bother with a 67MP camera at all? 33MP would likely be just fine for them.
Am I the only one that looks at sharpness on the pixel level, not all the time but to establish lenses and settings?
For me an image printed on A4 should look good as much as A0, both viewed at 10-12" away.
EBH
I have pointed out before that when using a zoom, the practical difference between a 24MP and 50MP rather small. I suspect 24MP is mostly enough when using zooms.
93_77mm by acurian, on Flickr
24MP / 77mm + bilinear upsample.
93_85mm by acurian, on Flickr
24MP / 85mm + bilinear upsample.
A1 70mm by acurian, on Flickr
50MP + 70mm
Quite clearly the contrast on the text is better on the 85mm sample. This means the difference between 24MP and 50MP with a zoom lens is less than a 1.2x crop. Its closer to 1.1x extra crop to my eye.
This is also the center of the frame, if we look at the corner of the frame the difference will be even smaller.
ruthenium wrote
The practical point here is that the smallest discernible by human eye element (point) of a printed image, or one that is presented on a display (at typical viewing distances and typical print/display sizes), is comprised of a group of pixels. These pixels are binned. Increasing the resolution by increasing the number of photo sites means that more of these are binned - there is no increased diffraction visible to the viewers. While viewing images at 100% is useful to verify whether an image is in focus and was not adversely affected my motion blur, this practice can be misleading when used to decide whether the image is acceptably sharp. An image is acceptably sharp when it looks sharp when viewed as a whole (e.g., as a print), from a reasonable and meaningful viewing distance. Thus, while the onset of diffraction is seen at f/8 on a full-frame system upon pixel-peeping, it is reasonable to expect that softening due to diffraction would not be seen when viewing the same image as a print or on a display even if the aperture had been further closed to f/11.Am I the only one that looks at sharpness on the pixel level, not all the time but to establish lenses and settings?
For me an image printed on A4 should look good as much as A0, both viewed at 10-12" away.
EBH
I have pointed out before that when using a zoom, the practical difference between a 24MP and 50MP rather small. I suspect 24MP is mostly enough when using zooms.
93_77mm by acurian, on Flickr24MP / 77mm + bilinear upsample.
93_85mm by acurian, on Flickr24MP / 85mm + bilinear upsample.
A1 70mm by acurian, on Flickr50MP + 70mm
Quite clearly the contrast on the text is better on the 85mm sample. This means the difference between 24MP and 50MP with a zoom lens is less than a 1.2x crop. Its closer to 1.1x extra crop to my eye.
This is also the center of the frame, if we look at the corner of the frame the difference will be even smaller.
Aug 21, 2026 at 03:04 AM
p.3 #15A7R6 and diffraction
Jack Flesher wrote:
gdanmitchell wrote
Jack Flesher wrote
gdanmitchell wrote
Jack Flesher wrote
aCuria wrote
No, the thread is about sharpness maximization, stopping down some reduces aberrations and increases sharpness. Jack is asking exactly how much to stop down, its a reasonable question.snapsy wrote
Jack's first sentence in his OP:"My question is what is the optimal aperture for DoF vs diffraction on the A7R6?"
I’m hearing from some it’s image dependent, apparently going by their gut instinct depending on the image. Others tend to limit their maximum aperture and more carefully set focus point for the image at hand so most of the important details are captured within the DoF of their accepted minimum aperture. Others focus stack.
My brain says there should be a calculable “ideal” point where the diffraction curves resolution falling with increased aperture intersects the DoF’s rising resolution gains with increased aperture curve.
If these is an “ideal point,” it is not going to be the same in every situation. And finding yourself a bit to one side or the other of that ideal isn’t going to make much of a difference.
It really is situational, with a range of factors playing into the decision. If you will print extremely large and. expect people to inspect at nose-length distances, that might pus you in the direction of focus bracketing. (Though if you look at highly regarded large prints of great work in galleries and at exhibitions you’ll almost always find that it isn’t as perfectly sharp as people imagine.) If you will reproduce at relatively smaller sizes and/or for less-close viewing (or for screens in general), you can worry a lot less about diffraction blur at the borderline apertures. If your subject really depends on super detail, you might be a bit more conservative about how small of an aperture you’ll use, but if that’s not the case in a particular shot you can use even smaller apertures and the photo will still work well.
I think that the answers come largely from experience making photographs and prints — something you have — and then applying that experience and your judgment situationally.
Regardless, the concerning point is I am seeing more detectable diffraction loss in my images than I’ve ever noticed previously. Whether that’s due to the camera sensor or better lenses —and given the somewhat insignificant changes post-processing sharpening adjustments make, it’s probably a combination of both— I’m noticing diffraction softening more and hence the deeper dive query.
Or perhaps good enough is, and I’m tilting at windmills…
It only seems like there’s “more diffraction blur” because when we look at, say, a 1000 x 1000 bit of an image from the higher resolution system we are simply looking at the same amount of blur but magnified more.
More good news: In some situations you can obtain some advantage from the higher resolution sensor and a slightlyl larger aperture and take advantage of lower diffraction at those apertures. Of course, gaining that extra little bit of potential sharpness has (as all things do) its own set of minuses. For example, you’ll get a smaller DOF. Unless you use really good lenses, it is possible (though not certain) that you could have some corner issues.
So it is a balancing act, isn’t it? If you need the extra DOF you can use he same apertures that you’d choose with a 30MP or 16MP FF camera and you won’t lose anything — you’ll still get an image that is at least as sharp as what you got with an older, lower res camera. If sharpness trumps that DOF increase you’ll choose the larger aperture and live with it or possibly resort of focus stacking or a TS lens instead.
I realize I am veering OT, and apologies. But this is somewhat relevant to the discussion I think. Here is an image...Show more →
Jack, note what you are doing - you are cropping a 20mm f/8 image by a factor of (roughly) 6!
The crop, as posted (that is, to the same size as the uncropped image) is equivalent to (should look the same as) an image taken at 120mm with the lens closed to f/48 (8 x 6 = 48).
Unsurprisingly, the crops can be expected to display diffraction softening (in addition to possible atmospheric effects on sharpness).
Aug 21, 2026 at 06:02 AM
p.3 #16A7R6 and diffraction
EB-1 wrote:
ruthenium wrote
The practical point here is that the smallest discernible by human eye element (point) of a printed image, or one that is presented on a display (at typical viewing distances and typical print/display sizes), is comprised of a group of pixels. These pixels are binned. Increasing the resolution by increasing the number of photo sites means that more of these are binned - there is no increased diffraction visible to the viewers. While viewing images at 100% is useful to verify whether an image is in focus and was not adversely affected my motion blur, this practice can be misleading when used to decide whether the image is acceptably sharp. An image is acceptably sharp when it looks sharp when viewed as a whole (e.g., as a print), from a reasonable and meaningful viewing distance. Thus, while the onset of diffraction is seen at f/8 on a full-frame system upon pixel-peeping, it is reasonable to expect that softening due to diffraction would not be seen when viewing the same image as a print or on a display even if the aperture had been further closed to f/11.Am I the only one that looks at sharpness on the pixel level, not all the time but to establish lenses and settings?
For me an image printed on A4 should look good as much as A0, both viewed at 10-12" away.
EBH
The retorical question "why bother with a 67MP camera" is a good one. All these pixels are almost never used directly, except in really large prints that few photographers are printing. A 4K display has only about 8MP.
I can think of two advantages of 67MP (or 102MP, as in the camera I have been using for the last 9 months).
One is obviously cropping. For example, my GFX100S II with the GF500mm F5.6 lens is full-frame equivalent to 395mm F4.4. When cropped to full-frame, it is 500mm F5.6, and when further cropped by a factor of 1.4, it is 700mm F8 (and still has 33MP in the 700mm crop). Thus the prime lens is effectively a 395-700mm F4.4-8 zoom. I find this useful.
The other possible advantage is with regard to noise. I am not 100% sure, as I am not an expert in this area, but pixel binning can theoretically improve the signal-to-noise ratio by a factor of the square root of the number of binned pixels. E.g., when downsizing from 80 to 20MP, the signal-to-noise ratio should improve two-fold.
Aug 21, 2026 at 06:28 AM
p.3 #17A7R6 and diffraction
ruthenium wrote:
The other possible advantage is with regard to noise. I am not 100% sure, as I am not an expert in this area, but pixel binning can theoretically improve the signal-to-noise ratio by a factor of the square root of the number of binned pixels. E.g., when downsizing from 80 to 20MP, the signal-to-noise ratio should improve two-fold.
SNR increases only when considered per pixel. The overall SNR in your image remains about the same. The underlying reason is that you have the same total amount of light recorded for an area, you just vary how you spread the photons into separate pixels.
The other possible advantage is with regard to noise. I am not 100% sure, as I am not an expert in this area, but pixel binning can theoretically improve the signal-to-noise ratio by a factor of the square root of the number of binned pixels. E.g., when downsizing from 80 to 20MP, the signal-to-noise ratio should improve two-fold.
SNR increases only when considered per pixel. The overall SNR in your image remains about the same. The underlying reason is that you have the same total amount of light recorded for an area, you just vary how you spread the photons into separate pixels.
Aug 21, 2026 at 06:38 AM
p.3 #18A7R6 and diffraction
Daran wrote:
ruthenium wrote
The other possible advantage is with regard to noise. I am not 100% sure, as I am not an expert in this area, but pixel binning can theoretically improve the signal-to-noise ratio by a factor of the square root of the number of binned pixels. E.g., when downsizing from 80 to 20MP, the signal-to-noise ratio should improve two-fold.This makes sense - thank you! Another thought: when there is much noise, can a larger number of pixels help denoising and reconstruction of a noisy image? For example, an image has 50% of the pixels displaying noise. Is there any advantage of a 100MP sensor vs. 24MP in this case? With 100MP, we shall have image information in 50MP out of 100MP against 12MP out of the 24MP. Shall the larger number of "good" pixels help denoising?
Aug 21, 2026 at 07:18 AM
p.3 #19A7R6 and diffraction
philip_pj wrote:
I'm interested in the 'viewing distance to diagonal' ratio people use for 'enjoyment/assessment viewing' (not necessarily editing), acknowledging the many factors that apply. I much prefer 2x (even for editing) but it appears the 'standards' do not agree with my tastes:
"most industry standards and consumer habits point to a viewing distance to diagonal ratio of about 1.2 to 1.6, which creates a comfortable 30-degree field of view. Older standard-definition rules suggested a much further ratio of 2.5 to 3.0 times the diagonal."
I don't find this close distance 'comfortable' at all. At 1.2 (some suggest 1.05!) you have to keep your...Show more →
Many prints have a picture within a picture which can better be seen and enjoyed when viewing up close. Yes viewing the entire print from distance gives you the co text the photographer is trying to get across, but the fine details in the print can only really be viewed when you come in close.
I'm interested in the 'viewing distance to diagonal' ratio people use for 'enjoyment/assessment viewing' (not necessarily editing), acknowledging the many factors that apply. I much prefer 2x (even for editing) but it appears the 'standards' do not agree with my tastes:
"most industry standards and consumer habits point to a viewing distance to diagonal ratio of about 1.2 to 1.6, which creates a comfortable 30-degree field of view. Older standard-definition rules suggested a much further ratio of 2.5 to 3.0 times the diagonal."
I don't find this close distance 'comfortable' at all. At 1.2 (some suggest 1.05!) you have to keep your...Show more →
Many prints have a picture within a picture which can better be seen and enjoyed when viewing up close. Yes viewing the entire print from distance gives you the co text the photographer is trying to get across, but the fine details in the print can only really be viewed when you come in close.
Aug 21, 2026 at 08:13 AM
p.3 #20A7R6 and diffraction
aCuria wrote:
With standards that low, why bother with a 67MP camera at all? 33MP would likely be just fine for them.
Am I the only one that looks at sharpness on the pixel level, not all the time but to establish lenses and settings?
For me an image printed on A4 should look good as much as A0, both viewed at 10-12" away.
EBHI have pointed out before that when using a zoom, the practical difference between a 24MP and 50MP rather small. I suspect 24MP is mostly enough when using zooms.
https://live.staticflickr.com/65535/54707281712_387bb330e1_b.jpg93_77mm by acurian, on Flickr
24MP / 77mm + bilinear upsample.
https://live.staticflickr.com/65535/54708337834_d65474b4b6_b.jpg93_85mm by acurian, on Flickr
24MP / 85mm + bilinear upsample.
https://live.staticflickr.com/65535/54707281812_1c926a1dfc_b.jpgA1 70mm by acurian, on Flickr
50MP + 70mm
Quite clearly the contrast on the text is better on the 85mm sample. This means the difference between 24MP and 50MP with a zoom lens is less than a 1.2x crop. Its closer to 1.1x extra crop to my eye.
This is also the center of...Show more →
About the idea that, say, “24MP is enough” — it is complicated:
1. It may be more than enough for many purposes. Few people print or otherwise view their photographs at sizes where 24MP would be insufficient. (Someone I know once “tricked” a group of very talented — and in two cases well-known and highly-regarded — photographers with a 12” x 18” print sourced from an iPhone!)
2. Many of us recall when 24MP was out beyond the far fringe of what we thought was possible. My first FF body had “only” 12MP… and it seemed amazing! I could make some pretty big prints that looked great with those images. In fact, I still can, and they look good now, too.
3. For some photographers, at least, there are still potential benefits from higher resolutions sensors. Potentially greater detail even at large reproduction sizes is one of them, but there are others, too. Areas of low contrast and subtle transitions may be smoother. the “grain size” of any noise will be smaller and potentially less visible. Greater cropping may be possible. Moire may be less likely to appear.
4. The subject matters, too. The extra detail may be useful in a highly detail shot, say of certain kinds of landscape or architecture, for example. This may be less the case in other types of photographs — perhaps in certain kinds of portraits or in some photographs of active subjects such as sports and some wildlife.
5. The manner of shooting makes a difference. There’s an argument that when you shoot handheld you are limiting the potential level of detail you’ll record since the camera will never be perfectly vibration/movement free, so you are less likely to take advantage of the higher potential detail resolution at the sensor compared to shooting with a perfectly stable tripod-based camera.
Finally, something else has changed. Back when I had the 12MP FF camera, I had to give up other kinds of performance to get it. That camera’s dynamic range was limited, it produced significant noise if I raised the ISO much at all, frame rates were quite low, and so forth. We are now at a point where we don’t give up all that much to get the higher resolution. For example, the new Sony A7r6, from all reports, while not quite equalling the lower resolution cameras optimized for speed, comes quite close… and a camera like the A1ii which is optimized for speed gives us resolution that less than a decade ago was available in only one FF camera.
YMMV.
- - -
chez wrote:
Many prints have a picture within a picture which can better be seen and enjoyed when viewing up close. Yes viewing the entire print from distance gives you the co text the photographer is trying to get across, but the fine details in the print can only really be viewed when you come in close.
The way I’ve put it is that part of the pleasure of enjoying a large print can be that it lets you take in the “all of it” from a distance and also find interesting additional detail when you get closer. (That’s not unique to photography. The same thing happens in other creative forms, including painting.)
EB-1 wrote
ruthenium wrote
The practical point here is that the smallest discernible by human eye element (point) of a printed image, or one that is presented on a display (at typical viewing distances and typical print/display sizes), is comprised of a group of pixels. These pixels are binned. Increasing the resolution by increasing the number of photo sites means that more of these are binned - there is no increased diffraction visible to the viewers. While viewing images at 100% is useful to verify whether an image is in focus and was not adversely affected my motion blur, this practice can be misleading when used to decide whether the image is acceptably sharp. An image is acceptably sharp when it looks sharp when viewed as a whole (e.g., as a print), from a reasonable and meaningful viewing distance. Thus, while the onset of diffraction is seen at f/8 on a full-frame system upon pixel-peeping, it is reasonable to expect that softening due to diffraction would not be seen when viewing the same image as a print or on a display even if the aperture had been further closed to f/11.Am I the only one that looks at sharpness on the pixel level, not all the time but to establish lenses and settings?
For me an image printed on A4 should look good as much as A0, both viewed at 10-12" away.
EBH
https://live.staticflickr.com/65535/54707281712_387bb330e1_b.jpg93_77mm by acurian, on Flickr
24MP / 77mm + bilinear upsample.
https://live.staticflickr.com/65535/54708337834_d65474b4b6_b.jpg93_85mm by acurian, on Flickr
24MP / 85mm + bilinear upsample.
https://live.staticflickr.com/65535/54707281812_1c926a1dfc_b.jpgA1 70mm by acurian, on Flickr
50MP + 70mm
Quite clearly the contrast on the text is better on the 85mm sample. This means the difference between 24MP and 50MP with a zoom lens is less than a 1.2x crop. Its closer to 1.1x extra crop to my eye.
This is also the center of...Show more →
About the idea that, say, “24MP is enough” — it is complicated:
1. It may be more than enough for many purposes. Few people print or otherwise view their photographs at sizes where 24MP would be insufficient. (Someone I know once “tricked” a group of very talented — and in two cases well-known and highly-regarded — photographers with a 12” x 18” print sourced from an iPhone!)
2. Many of us recall when 24MP was out beyond the far fringe of what we thought was possible. My first FF body had “only” 12MP… and it seemed amazing! I could make some pretty big prints that looked great with those images. In fact, I still can, and they look good now, too.
3. For some photographers, at least, there are still potential benefits from higher resolutions sensors. Potentially greater detail even at large reproduction sizes is one of them, but there are others, too. Areas of low contrast and subtle transitions may be smoother. the “grain size” of any noise will be smaller and potentially less visible. Greater cropping may be possible. Moire may be less likely to appear.
4. The subject matters, too. The extra detail may be useful in a highly detail shot, say of certain kinds of landscape or architecture, for example. This may be less the case in other types of photographs — perhaps in certain kinds of portraits or in some photographs of active subjects such as sports and some wildlife.
5. The manner of shooting makes a difference. There’s an argument that when you shoot handheld you are limiting the potential level of detail you’ll record since the camera will never be perfectly vibration/movement free, so you are less likely to take advantage of the higher potential detail resolution at the sensor compared to shooting with a perfectly stable tripod-based camera.
Finally, something else has changed. Back when I had the 12MP FF camera, I had to give up other kinds of performance to get it. That camera’s dynamic range was limited, it produced significant noise if I raised the ISO much at all, frame rates were quite low, and so forth. We are now at a point where we don’t give up all that much to get the higher resolution. For example, the new Sony A7r6, from all reports, while not quite equalling the lower resolution cameras optimized for speed, comes quite close… and a camera like the A1ii which is optimized for speed gives us resolution that less than a decade ago was available in only one FF camera.
YMMV.
- - -
chez wrote:
Many prints have a picture within a picture which can better be seen and enjoyed when viewing up close. Yes viewing the entire print from distance gives you the co text the photographer is trying to get across, but the fine details in the print can only really be viewed when you come in close.
The way I’ve put it is that part of the pleasure of enjoying a large print can be that it lets you take in the “all of it” from a distance and also find interesting additional detail when you get closer. (That’s not unique to photography. The same thing happens in other creative forms, including painting.)
Aug 21, 2026 at 09:05 AM