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06-11-2019, 09:05 AM   #31
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QuoteOriginally posted by normhead Quote
You are completely ignoring the effect of the overlap of the circles of confusion.
I guess downsizing might work the same way and looking at a print from further away, so when the blur is close to pin sharp it's not visible, but it become visible as soon as the blur of defocus become significant relative to pixels, same with diffraction.

There is also the relative sharpness in the frame. If I use my Samyang 85 1.4 wide open focused on a portrait, the person's face look sharp relative the blurred background. But in the center the Samyang 85 1.4 is not even as sharp as a Pentax 18-55 kit lens wide open. The perception of sharpness is relative: if you missed focus on the bird's eye, but other parts of the image like feather are sharp, no matter how much you downsize the image the bird's eye will never look sharp because there is an area next to it that's sharper.

06-11-2019, 11:20 AM   #32
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With modern magic maybe some details can come back.

06-12-2019, 05:48 AM   #33
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It doesn't matter what you do it will never be this.


You tend to be OK with the top one unless you already have lots of images with the bottom one. I almost didn't post the top one, it was kind of a whim.
06-12-2019, 05:56 AM   #34
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QuoteOriginally posted by normhead Quote
It doesn't matter what you do it will never be this.


You tend to be OK with the top one unless you already have lots of images with the bottom one. I almost didn't post the top one, it was kind of a whim.
Did you notice that I recovered details on your image?

06-12-2019, 06:09 AM   #35
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QuoteOriginally posted by vonBaloney Quote
Did you notice that I recovered details on your image?
Ya, impressive. Don't make me smack you upside the head.
06-13-2019, 04:12 AM   #36
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QuoteOriginally posted by normhead Quote
It doesn't matter what you do it will never be this.
It rarely is a case for landscapes. You stop the lens down to f/64, and eventually get circles of confusion confused with airy disks at the center, everything would become equally soft.
06-13-2019, 05:49 AM   #37
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QuoteOriginally posted by biz-engineer Quote
It rarely is a case for landscapes. You stop the lens down to f/64, and eventually get circles of confusion confused with airy disks at the center, everything would become equally soft.
Where the diffraction point is depends in part of how big the lens is. ƒ64 is necessary only on very large format cameras. Long lenses that are big.

QuoteQuote:
Worth noting that angular resolution and DOF/defocus is related to absolute aperture size, not f-number, so you can also just plug in the values for "f" to compare.
The iPhone 6 has f=4.15mm, a lens with similar FOV on an 8x10 has f=200mm.
200mm / 64 = 3.1mm -> the size of an f/64 aperture on a 200mm lens.
4.15mm / 2.2 = 1.9mm -> the size of on f/2.2 aperture on the iPhone 6.
Although the 8x10 will often have less defocus due to movements (photographer control of focal plane).
Group f/64 | Hacker News

Diffraction is caused by the size of the hole for the aperture, not the ƒstop per se. The size of that hole gets larger as the focal length of the lens gets longer. And the lager the format, the longer the focal length of the "standard" lens.

Last edited by normhead; 06-13-2019 at 05:56 AM.
06-13-2019, 05:56 AM   #38
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QuoteOriginally posted by normhead Quote
Diffraction is caused by the size of the hoel for the aperture, not the ƒstop our se.
Yes. Good to remind that.

06-14-2019, 03:19 AM   #39
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QuoteOriginally posted by normhead Quote
It doesn't matter what you do it will never be this.
Of course not. No matter how practical you example can be, my landscapes don't look like a yellow bird .
As you know there is a theoretical practice and practical theory, they are two different kind of animals
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