A BSI APS-C EOS R camera is coming in the second half of 2022 [CR2]

privatebydesign

I post too Much on Here!!
CR Pro
Jan 29, 2011
10,517
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You did crop the picture.
You are not saying anything incorrect.
But you are refusing to acknowledge or consider my point.
When you crop, print and decide how far away to view the picture, the DoF for that picture was already set inside the camera.
You could say that the DoF is already set for all the various combinations you decide.


Was that necessary?
Your point is wrong! My only challenge is finding a way for you to accept that. Why should I ‘accept your point of view’ if it is incorrect or, rather, counter to the definition of the term?

No, the depth of field was not already set because I, as the photographer, have no control over what you find acceptable sharp!

Was it necessary? Well I don’t know how else to phrase it. There is a term with a definition, I fully understand that term and several people in this thread don’t. It isn’t my opinion, it is a fact as determined by the accepted definition of the phrase, I can try to help or just not bother, so far trying to help/educate/correct the wrong hasn’t done much for me personally...


If I have 10/20 vision and my wife has 40/20 vision what is sharp to her is not sharp to me, my very measure of acceptable sharpness is different from hers. Ergo my perception of depth of field is different to hers even looking at the same photo on the same wall from the same distance.

Blows your mind doesn’t it? The same picture from the same distance can have different depths of field, areas of acceptable sharpness (the very definition of depth of field), for two people standing next to each other.

So to ‘standardize’ things a bit we work to CoC’s. Acceptable focus used to be defined as a person with average eyesight viewing an 8”x10” print from 12” away, but that was too narrow a definition given the vast differences in viewing distance and reproduction size and the move away from 8“x10” cameras and contact images from them. So a more universal way of working things out needed to be thought up, fortunately there are a lot of smart people out there and they came up with a way of taking the various format sizes into account. The diagonal of the format divided by 1500. d/1500. This gave a good approximation of the traditional ‘average‘ persons eyesight viewing an 8”x10” contact print at 12” and worked across all formats larger and smaller. But it is still based on the angle of view the final picture represents, move that image further away and your coc gets smaller in your view so you get more dof, move it closer and the reverse happens, you get less dof.

So answer me this, if the dof/coc/area of acceptable focus is defined as viewing an 8”x10” picture from 12” for a person with average eyesight, what happens to that dof/coc/area of acceptable focus if you move the picture further away? The depth of field changes, it increases, by the very definition of the term depth of field/area of acceptable focus.
 

privatebydesign

I post too Much on Here!!
CR Pro
Jan 29, 2011
10,517
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Over the last few years you have corrected my statements, sometimes the correction had nothing to do with the statement being made or subject. On this forum it gets to the point there is a discussion I want to be involved in, spend a few minutes typing a post and just delete it because I know someone will correct think something in it isn't just right.

This is a correct statement.
I do the same. Look at my posting history I am in and out because half the time I just can’t be bothered, after all I am the one trying to correct a misstatement here yet I am the one accused of bullying and mansplaning, though I don’t know who the woman is I was supposed to be doing that to....

I know it is, I was interested in the facts so I tested it and backed it up with images and detailed methodology so people could repeat it if they liked.
 

puffo25

EOS R5 - Fine art landscape, travel,astro and pano
Jul 18, 2017
120
46
56
italy
Hi all, I am a bit confused about those newest camera bodies... I own a Canon R5.
I do mostly landscape, nature, documentary, travel, portrait, astro, panoramic images, including milky way, northen light, star trails images...
I am NOT interested on sport, wedding, wilderness, indoor/commercial/prop photography.
I am looking for the future as a second camera body but NOT sure if those 2 new cameras might meet my needs?
Do you think those might be a good second camera body or I should wait further for example for the possible R2 or R1?
Please note: I do not want the R3 as high speed and heavy camera body is NOT what I need. I do not want the R6 because compared to the R5 does not add much (yes, a bit more tolerance in low light, but that is all in essence)....
Any suggestion is welcome.
 

puffo25

EOS R5 - Fine art landscape, travel,astro and pano
Jul 18, 2017
120
46
56
italy
Not now. But maybe in 1 or 2 years, just as second body, in case I shoot a lot and do not always to switch btw lenses all the time...
 

Dalantech

Gatekeeper to the Small World
Feb 12, 2015
111
89
We can disagree, but only one of us is right. I suspect you don't understand the role of the circle of confusion (CoC) in determining the DoF. You may want to read up on that a bit. It's why, for example, an image viewed at a small size appears to have deeper DoF. Here's an example where the hair and flower appear in focus at small viewing size, but in reality only the flower is in focus. The reduction in size of the full image increased the DoF because it changed the perceived sharpness of the image. The same is true in reverse – enlarging an image results in a shallower DoF.

View attachment 200620
"...changed the perceived sharpness...", but the depth of field really did not change. It is like saying that a smaller sensor gives you more depth of field, when all it is doing is allowing you to fill the frame with the subject at smaller magnifications and the drop in mag is responsible for the change in depth. Or like the illusion of depth that I create when I twist my wrist to lay the area of acceptable focus over the subject's face. The depth of field chart for the lens that I use only takes into account magnification and Fstop cause those are really the only two factors that matter when shooting macro.
 

Dalantech

Gatekeeper to the Small World
Feb 12, 2015
111
89
IF. But that's not the case. As a very simple demonstration, @unfocused stated that this statement by @Dalantech is correct:


But, it is not correct. Depth of field is not fixed when the shutter button is pressed. To claim that a false statement is true is not giving accurate information. And he has declined to give any sort of definition. Those aren't semantics, unless claiming the earth is flat is just a semantic distinction from it being (roughly) spherical.
I like the example that @unfocused gave in another reply: Depth of field does not change when I take off my glasses and everything is equally out of focus...
 
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Dalantech

Gatekeeper to the Small World
Feb 12, 2015
111
89
My rationale really has more to do with trying to make this more of a welcoming place. There are idiots who join this forum simply to make ridiculous statements and they deserve all the venom that they get. But there are others who get bullied for posts that are essentially correct. Over the years, I've seen many well-meaning contributors (including some very high caliber photographers) driven away because a handful of participants scour the site looking for arguments.
Over at the DP Review forum, a site that is a lot more toxic than this one, there are threads where people are wondering why forum participation is down. Some of them think it is just because more people are shooting with cell phones and not the increase of idiots who will say things, while hiding behind a keyboard, that they would never say in public.

Like you I absolutely hate getting into some of theses discussions because people will believe whatever they want and it is easy to rig a "test' for what they want to prove. Plus I have seen a lot of shooters driven out of macro by a community that is so hyper focused on absolute image sharpness that they cannot see the picture because the pixels are in the way. I have actually decided not to focus stack just to prove the pixel obsessed wrong :D

Pollen Covered Mining Bee by John Kimbler, on Flickr
 
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Dalantech

Gatekeeper to the Small World
Feb 12, 2015
111
89
He was wrong. Assuming that skill at something automatically confers technical understanding is silly. Muscle energy is always in the mind of Olympic athletes because it is limiting to their performance. How many of those athletes can diagram the glycolytic pathway or understand the role of creatinine in muscle function? I’d guess not many. I cannot run 100 meters in 10 seconds, but I understand muscle physiology. The fact that @Dalantech takes astounding macro images doesn’t mean he automatically understands the technical aspects of DoF any more than Usain Bolt's astounding speed means he automatically understands the sliding filament mechanism.
I will concede that you can change how depth is perceived, but you really cannot change depth of field after the shutter is pressed. The manual for most macro lenses has a chart that lists the depth of field at certain apertures and magnifications, but those are the only two factors that are taken into account. Can an image seem like it has more depth because you made a small print? Sure. But that does not mean that the actual depth changed.

I do not focus stack (to be honest at this point I kinda refuse to) and yet if I did not tell you that I shoot single frames you would ask me "How many frames did you take for that stack?". The way that I create the illusion of depth is simple: I pick a spot where I want the depth to start, like this bee's mandibles, and then twist my wrist to lay the area of acceptable focus over the critter's head.

Pollen Covered Mining Bee by John Kimbler, on Flickr

The amount of depth that I get is no different than the depth that anyone else would get, shooting at the same magnification and Fstop. The only difference is that I can picture the depth in my head and I know where it needs to be to make the most of it. So I would argue that I do understand the technical aspects of DoF better than most of the macro community, especially since most of them have to resort to focus stacking. I even get more detail in my images than a lot of them, even though my shots are "diffraction limited", due to the quality of my light.
 
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takesome1

EOS 5D Mark IV
Aug 23, 2013
1,549
205
100
None your business Alaska
Your point is wrong! My only challenge is finding a way for you to accept that. Why should I ‘accept your point of view’ if it is incorrect or, rather, counter to the definition of the term?

No, the depth of field was not already set because I, as the photographer, have no control over what you find acceptable sharp!

Was it necessary? Well I don’t know how else to phrase it. There is a term with a definition, I fully understand that term and several people in this thread don’t. It isn’t my opinion, it is a fact as determined by the accepted definition of the phrase, I can try to help or just not bother, so far trying to help/educate/correct the wrong hasn’t done much for me personally...


If I have 10/20 vision and my wife has 40/20 vision what is sharp to her is not sharp to me, my very measure of acceptable sharpness is different from hers. Ergo my perception of depth of field is different to hers even looking at the same photo on the same wall from the same distance.

Blows your mind doesn’t it? The same picture from the same distance can have different depths of field, areas of acceptable sharpness (the very definition of depth of field), for two people standing next to each other.

So to ‘standardize’ things a bit we work to CoC’s. Acceptable focus used to be defined as a person with average eyesight viewing an 8”x10” print from 12” away, but that was too narrow a definition given the vast differences in viewing distance and reproduction size and the move away from 8“x10” cameras and contact images from them. So a more universal way of working things out needed to be thought up, fortunately there are a lot of smart people out there and they came up with a way of taking the various format sizes into account. The diagonal of the format divided by 1500. d/1500. This gave a good approximation of the traditional ‘average‘ persons eyesight viewing an 8”x10” contact print at 12” and worked across all formats larger and smaller. But it is still based on the angle of view the final picture represents, move that image further away and your coc gets smaller in your view so you get more dof, move it closer and the reverse happens, you get less dof.

So answer me this, if the dof/coc/area of acceptable focus is defined as viewing an 8”x10” picture from 12” for a person with average eyesight, what happens to that dof/coc/area of acceptable focus if you move the picture further away? The depth of field changes, it increases, by the very definition of the term depth of field/area of acceptable focus.
You do realize that I have not disagreed with you on any of the points or statements you have made other than the initial.

The one I initially pointed out was this:
If you are of the opinion that DoF is set when you take the image you are wrong,

Google pops up with this definition: the distance between the nearest and the furthest objects that give an image judged to be in focus in a camera.
Interesting because that one says "in a camera"

Wikipedia says this: "depth of field (DOF) is the distance between the nearest and the farthest objects that are in acceptably sharp focus in an image."

So I give you this example, if I take a picture with my R5 and then review it in the view finder and "judge" to be in focus, the DoF was set when I took the image and "judged" in the camera.

If my only intent is to print that image at a certain size and view it in a certain way then determine what is "acceptably sharp focus" the DoF was still set when I took the image.

In both instances I set the aperture in the camera to get the desired DoF, the image was captured and I merely confirmed the result when I reviewed.
 

neuroanatomist

I post too Much on Here!!
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Jul 21, 2010
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The depth of field chart for the lens that I use only takes into account magnification and Fstop cause those are really the only two factors that matter when shooting macro.
This incorrect statement perfectly sums up your mistaken belief (and I suspect is the basis for the ‘real DoF’ @unfocused believes in).

I’ll give one more try, in the hopes that you, @unfocused, @Distinctly Average, @takesome1 and anyone else who erroneously believes DoF is fixed at capture or that there’s a ‘real’ (perception-independent) definition of DoF actually reads the following with an open mind and an honest attempt to understand.

The mathematical formula used to calculate DoF for charts and calculators is:

78403372-2879-4B4C-B6E2-AD7A3432E605.jpeg


In that equation, u is subject distance, N is the f/number, f is the focal length, and c is circle of confusion. The values for u, N and f are set at the time of image capture. But those are not the only variables.

Math being math, it is impossible to calculate DoF without a value for c. The CoC variable is what defines ‘acceptable sharpness’ and it incorporates the parameters of output size, viewing distance and visual acuity. so obviously c is going to vary based on factors that are all determined when the image is displayed and viewed, are not and cannot be set at the time of image capture.

Understandably, many photographers want a way to determine DoF ahead of time, but in reality that is impossible because it cannot be calculated for any image before the image is displayed and viewed (and because visual acuity matters, the actual DoF of any image can differ from one viewer to another).

Of course, those facts are completely unhelpful, and even if the true DoF cannot be known at the time of image capture, an approximation of DoF can be very helpful as a guideline for choosing the values —subject distance, f/number, and focal length— that can be determined before pressing the shutter button. Since the value of c cannot be determined before the image is captured, an approach commonly used in science is applied – making a set of defined assumptions that allow an unknown variable to be treated as a constant.

The industry-standard assumptions are an output size of an 8x10” print, a fixed viewing distance of 12”, and a visual acuity equivalent to 20/60 on a Snellen chart. Those assumptions allow assignment of a value for c, which enables calculation of a value for DoF. The specific value calculated for a given subject distance, f/number, and focal length is only the absolutely correct value for those specific viewing conditions. But since DoF is directly proportional to c, those assumptions are useful because they allow the comparison of relative changes in DoF resulting from the photographer’s choices of subject distance, f/number, and focal length, i.e. the things that a photographer can control directly at the time of image capture.

Those set assumptions for output size, viewing distance and visual acuity are the basis for the DoF values in charts, calculators, and are also what lens manufacturers use in the tables they include in the lens documentation and for the DoF markings on lenses with a manual aperture control ring. If it’s a chart you downloaded somewhere it probably doesn’t have those assumptions printed on the chart, but if you read the supporting information for any good online DoF calculator, they are stated. (Well, the print size and viewing distance are stated, usually along with a reference to visual acuity which is almost never quantified but can be back-calculated from the CoC values used and some knowledge about the basis of the modern version of Snellen’s eye chart.)

Because the output size is arbitrarily set to an 8x10” print, DoF calculators incorporate the input (sensor) size and thus the magnitude of enlargement into the assumptions for c. That’s why DoF calculators have you select your sensor size (and back in the day there were different printed charts for 35mm, medium and large format film). It's also why cropping an image in post but viewing the output at the same size as the uncropped image (e.g. filling the screen of your display) will change the DoF of the image.

To sum up, 'real depth of field' can only be determined if the output size, viewing distance and viewer's visual acuity are known. A DoF chart/calculator provides a useful approximation of DoF values based on a set of assumptions regarding output size, viewing distance, and visual acuity.

Because I don't expect you to simply take my word for it, I'll provide some quotes from identified sources that confirm what I posted above.

"It's important to note that DOF isn't a lens characteristic like focal length or aperture. It takes into account some subjective factors like print size and viewing distance." "DOF is at best a "fuzzy" concept, depending on subjective judgement of what appears to be sharp."

Bob Atkins DoF Calculator

(Worth noting that as Bob points out, commonly used DoF calculators ignore the effects of diffraction on DoF, but it should be obvious given that the definition of DoF includes a term such as 'acceptable sharpness' and anyone who's tried to get more DoF by shooting macro at f/32 knows that diffraction affects sharpness.)

"In order to calculate the depth of field, one needs to first decide on what will be considered acceptably sharp. More specifically, this is called the maximum circle of confusion (CoC), and is based on the camera sensor size (camera type), viewing distance and print size."
(The CIC calculator has a 'show advanced' feature that allows one to select the output size, viewing distance, and visual acuity, such that if you know ahead of time you want to make a large print you can adjust the calculated DoF values to reflect that pre-capture decision.)

"Most depth of field calculators you find online give DoF values based on an accepted Circle of Confusion (CoC). This CoC results from the combination of the selected camera sensor and the following viewing hypothesis: Print size of 8''×10'' (20cm×25cm); Viewing distance of 10" (25cm); Manufacturers standard visual acuity (the viewer can perceive details which size is roughly 0.01”). Remember that the Circle of Confusion establishes the frontier between what is considered to be in focus and out of focus in an image. The Circle of Confusion Calculatorwill help you learn more about it. Well, these assumptions work pretty well in most cases. But when you want to change the viewing conditions, you need to adjust the Circle of Confusion accordingly to get the adjusted depth of field values."

After reading the post above and the similar statements in just three of the many reputable sources on the subject, if you still believe that DoF values are determined only by factors set at the time of image capture I'd advise you to avoid any long ocean voyages because you may fall off the edge of the world.
 

takesome1

EOS 5D Mark IV
Aug 23, 2013
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None your business Alaska
Understandably, many photographers want a way to determine DoF ahead of time, but in reality that is impossible because it cannot be calculated for any image before the image is displayed and viewed (and because visual acuity matters, the actual DoF of any image can differ from one viewer to another).


After reading the post above and the similar statements in just three of the many reputable sources on the subject, if you still believe that DoF values are determined only by factors set at the time of image capture I'd advise you to avoid any long ocean voyages because you may fall off the edge of the world.
Nowhere did I say "only by factors set at the image capture.."
I could make a false claim and twist a few words as well and say that claiming that what you are saying when you take an image it has no impact on DoF.
The reality is that it is a package deal from the shot you take till you finally view it.
PBD comment "If you are of the opinion that DoF is set when you take the image you are wrong," is an absolute, while his thinking may be carry merit the statement is not always correct.

So according to your statement, lets say I shoot an object 20' away with nothing in the foreground with my 24mm lens on a FF body at f/8. The DoF calculator gives 6.8' to Infinity. You are saying I would be wrong to expect the picture to have an acceptable focus throughout. You may be right, if the DoF is determined by someone wearing reading glasses 20' away.

Truthfully the entire discussion is semantics, especially when trying to apply facts and absolutes about "DOF is at best a "fuzzy" concept".

While the earth is not flat, you would be incorrect in claiming it is round according to Scientific American:
 

neuroanatomist

I post too Much on Here!!
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Jul 21, 2010
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Nowhere did I say "only by factors set at the image capture.."
You did not, but that's exactly what @Dalantech and @unfocused claimed, and it's patently false.

While the earth is not flat, you would be incorrect in claiming it is round according to Scientific American:
I would be incorrect, if I had claimed that...but, I didn't.

Those aren't semantics, unless claiming the earth is flat is just a semantic distinction from it being (roughly) spherical.
 
Sep 30, 2021
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Yes, and I shouldn't allow myself to be drawn into this meaningless discussion. Same old flawed arguments and mansplaining from the same people. Same links to pseudo-science. Now, depth of field has become all about perception. I only need to take off my glasses and suddenly depth of field increases because everything looks to be of equal sharpness.

Not worth my time explaining. @Distinctly Average and @Dalantech you are still correct and don't be intimidated by the bullies on this forum who say otherwise.
Don’t worry, I fully understand that some people will argue black is white just before they get squished on the next zebra crossing.
 
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neuroanatomist

I post too Much on Here!!
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Jul 21, 2010
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Don’t worry, I fully understand that some people will argue black is white just before they get squished on the next zebra crossing.
Indeed, and some people will continue to argue that established facts are false or 'pseudo-science' while demonstrating a complete inability to provide actual evidence to support their erroneous views. That attitude has become even more popular with the rise of "fake news" that we've seen lately.
 

unfocused

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Jul 20, 2010
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@privatebydesign, I wanted to give some time for the dust to settle before responding.

You asked why I referred to the discussion as "mansplaining." I was using it in a generic sense to describe the practice (mostly of men) of "explaining" some fact or concept to someone who doesn't need or want the explanation. I felt, and still feel, that is an appropriate description of much of this discussion. Every participant in this discussion understands the topic and doesn't really need anyone else to explain it to them. There are disagreements over some aspects, but it really is splitting hairs. (That is my perspective and may not be shared by others).

I certainly know that I have a tendency toward mansplaining as much as anyone and I have two ex-wives who would happily attest to that. I apologize for any offense to you. I appreciate that you are well-intentioned and generally do not engage in the kind of attacks that others on this forum so readily engage in.

This topic, like certain other topics (equivalence comes to mind) have been so thoroughly debated that there really is no point in further discussion. No one is going to win over anyone else and no one is going to benefit from further debate. There is enough truth to everyone's position to allow all participants to feel they are right and others are wrong. I'm going to do my best just to walk away from it and accept that no one ever "wins" an argument on the internet.
 

neuroanatomist

I post too Much on Here!!
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Jul 21, 2010
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…no one ever "wins" an argument on the internet.
While that’s probably true, when on one side you have fact backed up with information from multiple, reputable sources and on the other side you have statements made with no attempt to provide external supporting information and an ‘I’m going to take my marbles and leave because I don’t want to hear an explanation’ attitude, it’s quite evident who “won” even if those making incorrect and unsupported claims never actually capitulate.
 
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