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04-21-2016, 02:21 PM   #166
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QuoteOriginally posted by osv Quote
what shutter speeds did i use to take the sharp pics that i've posted?

do you really think that all shutter speeds need "a monumentally solid tripod" and remote control over the camera?
Wouldn't the slightest movement of the camera after you have obtained 'perfect focus' mean you would have to focus again and again and again.. or would you rely on DoF to cover any slight imperfections?

04-21-2016, 02:25 PM   #167
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QuoteOriginally posted by emalvick Quote
Perfect focus does not equal acceptable focus...
that makes no sense at all.

QuoteOriginally posted by emalvick Quote
What I see when you say DOF = Perfect focus is that you have a loose definition of perfect.
those comments indicate a lack of understanding of what focus really is.

what we perceive as a region of perfect focus is nothing more than small and varying amounts of dof blur, even with the best 100% viewing capability.

that should be obvious by the depth of the area in focus.

---------- Post added 04-21-16 at 02:49 PM ----------

QuoteOriginally posted by mohb Quote
Wouldn't the slightest movement of the camera after you have obtained 'perfect focus' mean you would have to focus again and again and again.. or would you rely on DoF to cover any slight imperfections?
that makes sense to me, depending on the shutter speed... there is no magic place where sharpness always ends and dof starts.

with a dslr you are fighting both mirror slap and shutter vibration.

higher shutter speeds can freeze camera movements like that: Sony a7R, a7RII shutter shock: Sony Alpha Full Frame E-mount Talk Forum: Digital Photography Review

---------- Post added 04-21-16 at 02:59 PM ----------

QuoteOriginally posted by emalvick Quote
All I see that makes you different is that you don't find what has been called acceptable as acceptable for you, which is fine. You essentially define depth of field as an area that you consider as "perfect" focus, which in terms of real physics is just your limit on what is acceptable.
dragging physics and false geometrical constructs into this discussion has ruined it.

"But some like to use DOF to “correct” focus issues, because they are concerned that either the point they had chosen to focus upon, or the technique they were using, would otherwise produce a fuzzy image. There is nothing, nothing in camera or post that will fix a focus problem! You want the subject sharp, so it has to be sharp from your camera and focusing technique!"
Just What is Sharp? Moose Peterson | explora

Last edited by osv; 04-21-2016 at 02:50 PM.
04-22-2016, 05:49 AM   #168
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QuoteOriginally posted by osv Quote
that makes no sense at all.



those comments indicate a lack of understanding of what focus really is.

what we perceive as a region of perfect focus is nothing more than small and varying amounts of dof blur, even with the best 100% viewing capability.

that should be obvious by the depth of the area in focus.

---------- Post added 04-21-16 at 02:49 PM ----------



that makes sense to me, depending on the shutter speed... there is no magic place where sharpness always ends and dof starts.

with a dslr you are fighting both mirror slap and shutter vibration.

higher shutter speeds can freeze camera movements like that: Sony a7R, a7RII shutter shock: Sony Alpha Full Frame E-mount Talk Forum: Digital Photography Review

---------- Post added 04-21-16 at 02:59 PM ----------



dragging physics and false geometrical constructs into this discussion has ruined it.

"But some like to use DOF to “correct” focus issues, because they are concerned that either the point they had chosen to focus upon, or the technique they were using, would otherwise produce a fuzzy image. There is nothing, nothing in camera or post that will fix a focus problem! You want the subject sharp, so it has to be sharp from your camera and focusing technique!"
Just What is Sharp? Moose Peterson | explora
one should be careful regarding a source named "Moose" as definitive.
04-22-2016, 01:52 PM   #169
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QuoteOriginally posted by osv Quote
dragging physics and false geometrical constructs into this discussion has ruined it.
Ruined it because it's correct. You're the one that talks in absolutes. Well, I'm sorry but physics is what is absolute. Whether you like it or not, you can't break the laws of physics or math. They are what they are. There is nothing false about them.

What I said of course makes no sense, because I restated what you stated, which often makes no sense.

But you are the one that is the all great being and photographer. You are the one who's theories trump physics and are the absolute right. And we should all bow out in disgrace, as I'll do now. I'll take my physics and misconception of DOF and shoot a landscape with an infinite DOF and be happy with the misfocused mountains because I don't understand what perfect focus means.

04-22-2016, 03:34 PM   #170
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QuoteOriginally posted by emalvick Quote
Ruined it because it's correct.
it wasn't correct, you yourself claimed that the two-dimensional depthless plane construct that john poirier posted was wrong, because lenses don't project a perfectly flat plane of focus... his failed post was a perfect example of how physics and geometrical constructs ruined the thread.

you are unable to explain the "Perfect focus does not equal acceptable focus" gibberish that you posted, and you've convinced reh that there are two planes in a dof field so no, i don't see anyone really using the laws of physics or math correctly in this discussion, all it's done is create endless arguments.
04-22-2016, 05:45 PM   #171
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QuoteOriginally posted by osv Quote
dragging physics and false geometrical constructs into this discussion has ruined it.
Thank you for making this post, because it explains what has been happening around here. I had been about to post a response to your posts #34 & #43 on page 3; I finally understood what you thought you were seeing, and how your use of words hid the truth from both you and us, but then this post came along. Mathematics is a precise language, known to all practitioners of the physical sciences and engineering, and used by them to communicate precisely with each other. It is the second, if not the first, language of the engineers who design our fine optical equipment, and of those who write the articles you love to quote without actually understanding what they say. Now I understand how you can quote words from Canon without understanding that those words exactly oppose the theory you're advocated for. Trying to talk about optics and related subjects without understanding math is like trying to discuss paintings with a blind person. Understanding how you feel left me free to give up on my explanation and spend my free time today on our deck on the more likely to succeed task of watching for a flying pig, as well as enjoying the birds and squirrels.

---------- Post added 04-22-16 at 08:47 PM ----------

QuoteOriginally posted by emalvick Quote
Ruined it because it's correct. You're the one that talks in absolutes. Well, I'm sorry but physics is what is absolute. Whether you like it or not, you can't break the laws of physics or math. They are what they are. There is nothing false about them.

What I said of course makes no sense, because I restated what you stated, which often makes no sense.

But you are the one that is the all great being and photographer. You are the one who's theories trump physics and are the absolute right. And we should all bow out in disgrace, as I'll do now. I'll take my physics and misconception of DOF and shoot a landscape with an infinite DOF and be happy with the misfocused mountains because I don't understand what perfect focus means.
Thank you for your effort. You made every chance to bring light here and turn down the heat. Your exit probably makes more real sense than your entrance did, and I plan to do the same thing in just a few minutes.

---------- Post added 04-22-16 at 08:54 PM ----------

QuoteOriginally posted by osv Quote
you are unable to explain the "Perfect focus does not equal acceptable focus" gibberish that you posted, and you've convinced reh that there are two planes in a dof field so no, i don't see anyone really using the laws of physics or math correctly in this discussion, all it's done is create endless arguments.
You seem to forget that you cheered for and embraced emalvick's two plane explanation in #156 before I explained it to you in #159 {I also explained it in #157 but you quibbled over another issue in #158, so your understanding and upset response were briefly delayed}

And now you may blather on without fear of response from me. {Today on our deck was so much more fun than this}

Last edited by reh321; 04-22-2016 at 05:57 PM. Reason: post script
04-22-2016, 06:37 PM   #172
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QuoteOriginally posted by reh321 Quote
Understanding how you feel left me free to give up on my explanation and spend my free time today on our deck on the more likely to succeed task of watching for a flying pig
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