Critique Air-Fried Spring Rolls --- Prefer Focus-stacked or Not?

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Mike's new Z6 has diffraction compensation
I don't have the camera yet, but that information is new to me and well worth taking the time to completely understand. Thanks!

A decent Micro lens is designed to be used at smaller apertures therefore diffraction is less of a problem.
That would perhaps explain why I remember that f/18 on my macro lens is pretty darn sharp. Even so, I will examine those details to be sure that there isn't a better aperture to use when focus stacking.
 
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I also prefer the first image. To me it's more natural to have an out of focus area.
The front of the exposed roll in Photo 1 is not as sharp as that in the second picture which would make it pop more.
Interesting to see your progression with this facet of photography.

One question I have is how do you not end up with an HDR look when images are stacked?
 
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The front of the exposed roll in Photo 1 is not as sharp as that in the second picture which would make it pop more.
Your eyes might be better than mine. When viewing that area of the two images side-by-side at 100% on my monitor, I don't notice any difference in sharpness. The two photos were post-processed independently (using different settings) out of necessity, so it's possible that perception of sharpness is being influenced by different amounts of mid-tone contrast and texture being applied. Even so, both images look about as close to the same in that area as I can get them.

If you're not using a profiled and calibrated monitor, that could explain an appearance that seems different for you.

how do you not end up with an HDR look when images are stacked?
I assume you believe the stacked image doesn't have the appearance of HDR. Considering that HDR is a completely separate process from focus stacking and that I used no HDR processing on any of the focus-bracketed images, I don't really know how to answer that question. Perhaps run that by me again.
 
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Your eyes might be better than mine. When viewing that area of the two images side-by-side at 100% on my monitor, I don't notice any difference in sharpness. The two photos were post-processed independently (using different settings) out of necessity, so it's possible that perception of sharpness is being influenced by different amounts of mid-tone contrast and texture being applied. Even so, both images look about as close to the same in that area as I can get them.

If you're not using a profiled and calibrated monitor, that could explain an appearance that seems different for you.



I assume you believe the stacked image doesn't have the appearance of HDR. Considering that HDR is a completely separate process from focus stacking and that I used no HDR processing on any of the focus-bracketed images, I don't really know how to answer that question. Perhaps run that by me again.
I have the advantage of a recent trip to the ophthalmologist so I know my eyesight is verified as 20/20, anyway it wasn't a criticism just an observation on my part.

My reference to HDR is that that process involves combining multiple images albeit at difference exposure settings. Apparently an overcooked HDR image can look "grungy"/over processed so I was curious how combining multiple images from different focus distance settings doesn't result in the same look, if that makes sense now.
Thanks.
 
I have the advantage of a recent trip to the ophthalmologist so I know my eyesight is verified as 20/20
I went to two eye doctors in adjacent buildings about two hours apart. One said my eyes are 20/20 and one said my eyes are 20/25. They're probably both wrong.

it wasn't a criticism just an observation on my part.
Though I took it as you intended, I'm always thrilled to take reasoned criticism.

My reference to HDR is that that process involves combining multiple images albeit at difference exposure settings. Apparently an overcooked HDR image can look "grungy"/over processed so I was curious how combining multiple images from different focus distance settings doesn't result in the same look, if that makes sense now.
Yes, I think I understand you now.

Keep in mind that my total life experience with focus stacking is that I've made only two stacked photos using my own focus-bracketed images; I probably don't know enough about this stuff to give you an adequate answer and maybe others can help.

In the case of Photoshop CC, which I used to make this stacked photo, there is only one algorithm that I have found, so there are no settings about that the user can mess up. Also, upon examining all parts of the image at 100%, I was lucky that everything was fine; there was no need to tweak any of the layers included in the stack. If I had found problems and tried to correct them, I might have accidentally made them no better or even worse.

I used Helicon Focus to make the stacked image in a different thread. It (like Zerene Stacker) has two algorithms that can be used at the same time at varying degrees. (Example: one at 30% and the other at 70% if I remember correctly.) I used only the default setting and when viewing the results at 100%, I again saw no problems. If I hadn't used the default settings and if they hadn't worked so well, perhaps the issues you mention might have occurred.
 
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I have the advantage of a recent trip to the ophthalmologist so I know my eyesight is verified as 20/20, anyway it wasn't a criticism just an observation on my part.

My reference to HDR is that that process involves combining multiple images albeit at difference exposure settings. Apparently an overcooked HDR image can look "grungy"/over processed so I was curious how combining multiple images from different focus distance settings doesn't result in the same look, if that makes sense now.
Thanks.
all exposures are the same - only the focus changes.
 
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all exposures are the same - only the focus changes.
I know that but I'm curious to know as to why when they're stacked the photo doesn't have that overprocessed HDR look or does that look only happen from too many different exposed images combined and combining images with the same exposure wouldn't produce that
 
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The vote about preference for the first or second image is currently tied. Though the data is such a small sampling, this speaks volumes to me that both looks are so acceptable, especially because all of the reasons given make so much sense.

When tallying the vote, I excluded my own vote. That's because I think I'm influenced by knowing the appearance, taste and texture of the spring rolls and am the only person voting who has that information.
 
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I should probably check the lens again, but I seem to remember from quite awhile ago that f/18 seemed to be as sharp as when using larger aperture settings.
I checked the lens again, not using any kind of scientific method, instead putting the lens through the real-world pace of photographing a printed surface, which is typical for me because of the number of wine labels I photograph up close.

The largest aperture on the lens is f/2.8 when the focus ring fully contracts the lens. The smallest aperture is f/64 when the focus ring fully extends the lens. Depending on the focal distance, it's possible that only one of those extremes is possible. It's also possible that neither of those extremes is possible.

To my eye (which is most important because I'm the only person who gets to look at my images at 100% :D ), the range of f/8 to f/22 are equally sharp and all apertures at least one stop beyond that range are not quite as sharp.

Conclusion: When focus stacking, I'll plan to use f/16. That's because the Sunny 16 Rule makes it easy to remember and because f/16 is always available regardless of the focal distance.
 
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I checked the lens again, not using any kind of scientific method, instead putting the lens through the real-world pace of photographing a printed surface, which is typical for me because of the number of wine labels I photograph up close.

The largest aperture on the lens is f/2.8 when the focus ring fully contracts the lens. The smallest aperture is f/64 when the focus ring fully extends the lens. Depending on the focal distance, it's possible that only one of those extremes is possible. It's also possible that neither of those extremes is possible.

To my eye (which is most important because I'm the only person who gets to look at my images at 100% :D ), the range of f/8 to f/22 are equally sharp and all apertures at least one stop beyond that range are not quite as sharp.

Conclusion: When focus stacking, I'll plan to use f/16 (easy to remember because I've known about the Sunny 16 rule for decades and because f/16 is always available regardless of how little or far the lens is extended).
Mike,

Depending on which version of the lens you have got, test results (mtf charts) tend to suggest that it is at its best at around f4/5.6. That is not to say that it is unsharp at f16, but that it is sharper at f5.6.
 
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Mike,

Depending on which version of the lens you have got, test results (mtf charts) tend to suggest that it is at its best at around f4/5.6. That is not to say that it is unsharp at f16, but that it is sharper at f5.6.
To my eye, the lens is not quite as sharp at f/5.6 as at f/16. When my eye and mtf charts disagree, I can't imagine any reason to make a photo in accordance with the charts. That's because nobody spends remotely as much time viewing my images as I do.
 
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Hi Mike. Normally I would prefer some part of an image to be OOF in food photography. But for this particular image, I prefer #2. It looks so good and inviting.
 
the range of f/8 to f/22 are equally sharp and all apertures at least one stop beyond that range are not quite as sharp.
test results (mtf charts) tend to suggest that it is at its best at around f4/5.6.
When I examined the details of sharpness of my Nikon 35mm f/2 prime lens, I used a different subject that reveals greater detail in the material the stuff is printed on. So, I also mounted the Tamron 90mm macro again. Based on that testing, f/8 was ever so slightly better to my eye for both lenses. That's what I'll go with.
 
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