snapsy 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.
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snapsy wrote:
Jack's first sentence in his OP:
"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.
Aug 20, 2026 at 10:05 AM
Previous versions of Jack Flesher's message #17092130 « A7R6 and diffraction »
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.