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10-06-2014, 07:48 AM   #1
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Very informative.

Glad I'm not with those "other" companies.



10-06-2014, 09:36 AM - 1 Like   #2
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Very interesting.... well explained. But doesn't address the issue in terms of photographers that usually want more DoF, not less. He takes the approach taken by all those who advance this type of argument, that less DoF is the standard, and implies we should all want that in all our images, to the point he acts as iff that should be the defining factor in all our images.

What he doesn't address, is the relative lack of difference between 100 ISO APS-c and 200 ISO FF. Or 100 ISO APS-c and 100 ISO because there just isn't that much difference at that end of the curve in terms of noise ratios. The question isn't whether FF is better, it always will gather more light, it will always be technically better, the question is will it e visually better. He makes that point by suing for his APS-c examples my absolute top end ISO for my APS_c gear. While I tend to use 10-200 and 400 max. So what's missing is that you mitigate the damage done by having a smaller sensor by using 100-400 ISO.

In that sense he's just as bad as those he criticizes. If he were honest, he would have included MF, he produces this whole video as if MF doesn't exist, showing that FF does not collect more light than every other sensor, he implies by omission that it does, that FF is one of the many stops on a continuum, and that there are good reasons for many of the compromises smaller formats accept. And he lies about the reasons people buy smaller cameras.

If he was here, I'd use the comparison of my buddy Dave. Dave knows if he sits where I sit, in my blind and shoots with his canon 1:800 zoom, he won't get the IQ I get with my APS-c and DA*60-250. He knows that dude. He isn't being fooled, despite your assertion that he is being He's a birder looking for maximum IQ. But he's looking for maximum IQ in a lightweight package. And he's decided the Canon point and shoot is the maximum he'll carry. He hasn't been conned, he hasn't bought the manufacturer cool aid. He's bought exactly what he wants. And he was able to do that without the rigamarole you've posted in this video, which would have been unnecessarily long, boring and pointless, because it doesn't use the parameters he uses when he selects a camera.

As for ISO being irrelevant? Irrelevant to who. Irrelevant to narrow DoF freaks, of which he is apparently one. All I want to do is figure what my exposure is with the camera I'm using, I could care less what the DoF is, I can see that through my viewfinder. I don't need to calculate that. And again if he were here, I would ask him, "what is the value of calculating something you can see? Why not just see it and adjust? " There simply is no good answer for that. All I can say about this guy is, he's selling his book. He's taking advantage of photographic newbies and getting into areas that are less essential than about any other aspect of photography. Like many posters on the forum. he's a navel gazer. He wants to discuss ad infinitum with mathematical formulas, simple things that can be understood looking at your prints.

The same basic rules apply...
If your images are too noisy for you liking, go to a larger format.
If you like wide DoF images, you'll probably be happier with a smaller lighter format.
You can say that without mention of FF or APS-c, but he chose not to.

FF and narrow DoF is not some arbitrary standard that everything should be measured against, even though he does his absolute manipulative best to make it so in his video. His logic is insane. There was way more difference between the DoF, noise etc. in film days than there is in digital. You had film formats from 8x10 to microfiche. And ISO was not designed nor ever meant to take DoF into account. On that point he is simply dead wrong, and completely lying. it wasn't that it didn't exist back then, it existed more than it does now, it was that the standard was never meant to include DoF, only the sensitivity of the emulsion used. He's just another one of the idiots trying to make ISO into something it was not designed to be.

Looking at my buddy Dave and myself... for most people, the portability of the camera is the biggest factor considered. Not "that creamy bokeh most professional photographers admire." And that where he completely misleads his audience. That creamy bokeh that "professional photographers admire" is not universally sought after, and can be achieved in different ways when it is desired. And like most dissertations of this type, because the original premise is flawed, the conclusions are flawed. Creamy out of focus areas are not the defining factor in photography. So his whole argument is biased. And the defining factor in noise is, where is the cutoff in ISO for the noise you'd accept. If like me your defining ISO is about 400, and you can work with that, then APS-c is just fine. That there is something that might be in some ways better makes no difference if you can work with what you've got. And the failure of his logic would be, he provides no information to explain why you shouldn't be happy with the tiniest of sensors, if you are. 95% of all camera buyers are going to look at this video and go "pffft I still like my camera." Some dude sitting in his little room expelling to people why their gear isn't good, that's just rude. What's good is not your decision dude. Whether of not people should want creamy bokeh or lower noise is not your decision. even though your sole video seems to be based on your assumption that you have something to say about it.

I get really tired of these guys. it's not that they are wrong. They aren't within their narrowly defined area of focus. it's that they focus on tiny bits of reality that it just doesn't make any sense to focus on. DoF is not the defining factor in why most peoples images are useful or not. Correct exposure is. Thats what ISO is for. This poor dude at the same time he criticizes it admits he can't work without it as it is. Too funny.
10-06-2014, 10:01 AM   #3
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Great video, even though I knew about the facts it's really nicely explained.
10-06-2014, 10:16 AM - 2 Likes   #4
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Sorry, I could not watch the whole thing, Way too much misinformation.

First of all, ISO does mean something, International Standards Organization.
International Organization for Standardization. This organization sets the standards for Light capacity of film and digital cameras. The standard is necessary to ensure the uniform like capacity of all photographic medium. It gives us reasonable transition between film and digital media. Without it, we would be thrown back into the 1700s, when there was no standard for any photographic medium.

Next, It is not the sensor size that determines the Light capacity and noise. It is the pixel size and amplifier. You can have the same noise emitted from a full frame sensor as you can a crop sensor given the same size pixel and Amplifier system.

However he was using the correct math. He just applied it in the wrong place.

It's videos like this that confuse people. People who claim to know what they are doing, and for the most part they do, but apply the knowledge in the wrong way.

I may not be an expert photographer, but I've been dealing with electronics and photography long enough to know that at least some of the information In this video is not correct.

10-06-2014, 10:27 AM   #5
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Had a good time watching this video.
10-06-2014, 11:44 AM   #6
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QuoteOriginally posted by tabl10s Quote
Glad I'm not with those "other" companies.
Pentax does it just like all APS-C manufacturers. He just doesn't mention Pentax because Pentax is such a small player.

Go to B&H Photo and look at the DA* 55mm F/1.4 lens. The last line in the overview reads:

Essentially equivalent to an 82.5mm f/1.4 lens upon 35mm SLR cameras

An 82.5mm F/1.4 lens would have an aperture area of 2727.3 mm^2
The 55mm F/1.4 lens has an aperture area of 1211.81 mm^2.

The aperture on a 55mm lens would need to be F/1.0 in order for it to equal the 82.5mm F/1.4 in terms of quantity of light projected on the sensor.

The area of aperture on an 82.5mm F/1.4 lens would be 2.25x larger than the 55mm F/1.4. At F/1.4 the 55mm does not project as much light onto the sensor as the 82.5mm lens. Pentax compensates for this by applying more digital amplification so that all settings being equal they produce images of the same level of brightness.
10-06-2014, 01:00 PM - 1 Like   #7
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QuoteOriginally posted by Winder Quote
Pentax does it just like all APS-C manufacturers. He just doesn't mention Pentax because Pentax is such a small player.

Go to B&H Photo and look at the DA* 55mm F/1.4 lens. The last line in the overview reads:

Essentially equivalent to an 82.5mm f/1.4 lens upon 35mm SLR cameras

An 82.5mm F/1.4 lens would have an aperture area of 2727.3 mm^2
The 55mm F/1.4 lens has an aperture area of 1211.81 mm^2.

The aperture on a 55mm lens would need to be F/1.0 in order for it to equal the 82.5mm F/1.4 in terms of quantity of light projected on the sensor.s.
An 1.4 lens is equal to an 1.4 lens regardless of format. Aperture is not defined by DOF but by exposure. DOF is mentioned nowhere in the definition of a lens aperture.
Different formats are not supposed to collect the same amount of light. Insisting on "equivalence" is missing the point entirely.

Haven't seen the video but all these zealots (who should read up upon exposure theory) do the same mistakes:
1) Insisting that different formats should have the same output and/or collect the same amount of light. This is wrong according to the theory of exposure. If it was correct a Pentax 645 should be compared to a cell phone.
2) Using one format as benchmark; usually FF. This is cheating. By this method only the properties of the reference format is used as properties smaller formats has to comply with. Not the other way around.This is only a one-sided biased opinion. Obviously for two lenses to be DOF equivalent they both have to do the same. Ie an equivalent FF lens must be able to do what the smaller format lens does as well DOF wise to be "equal".
3) Pretending that DOF is only depending on aperture and equivalent focal lenghts. It isn't. It is dependent on aperture, focal lenght, focusing distances, and subject magnification. Ie lenses claimed to be DOF equivalent are patently not. Not even wide open.
Some may be surprised if they put "equivalent" lenses into a DOF calculator. For comperable lenses (eg prime vs prime, zoom vs zoom) you'll find that the smaller format lens usually has thinner minimum DOF than the larger. This is because it has larger maximum magnification.

Last edited by Pål Jensen; 10-06-2014 at 01:44 PM.
10-06-2014, 02:04 PM   #8
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QuoteQuote:
Published on May 16, 2014
Am I in a time-warp?

This video has been posted in these forums about 10 times already, starting 5 months ago, in 3 or 4 different sections of the forum. And we've already had exhaustive discussions about equivalence and everything else here triggered by it.

Pls make it stop.

10-06-2014, 02:20 PM - 1 Like   #9
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QuoteOriginally posted by Pål Jensen Quote
An 1.4 lens is equal to an 1.4 lens regardless of format. Aperture is not defined by DOF but by exposure. DOF is mentioned nowhere in the definition of a lens aperture.
Of course it is. I said nothing to the contrary, but since F-stop is a function of focal lengtht you can't directly compare different focal lengths.....and I never mentioned DoF. Are you quoting the right post?

QuoteOriginally posted by Pål Jensen Quote
3) Pretending that DOF is only depending on aperture and equivalent focal lenghts. It isn't. It is dependent on aperture, focal lenght, focusing distances, and subject magnification. Ie lenses claimed to be DOF equivalent are patently not. Not even wide open.
Some may be surprised if they put "equivalent" lenses into a DOF calculator. For comperable lenses (eg prime vs prime, zoom vs zoom) you'll find that the smaller format lens usually has thinner minimum DOF than the larger. This is because it has larger maximum magnification.
Did I even type "DoF" in any of the post you quoted? DoF is irrelevant to the conversation. Why the tangent?

---------- Post added 10-06-14 at 04:26 PM ----------

QuoteOriginally posted by rawr Quote
Am I in a time-warp?

This video has been posted in these forums about 10 times already, starting 5 months ago, in 3 or 4 different sections of the forum. And we've already had exhaustive discussions about equivalence and everything else here triggered by it.

Pls make it stop.
This is Pentax Forums..... Everyday is Groundhog Day...

Last edited by Winder; 10-06-2014 at 02:27 PM.
10-06-2014, 02:44 PM   #10
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This video has been discussed (more like argued) extensively in this thread:

https://www.pentaxforums.com/forums/169-pentax-full-frame/262253-pretty-good-...uivalence.html
10-06-2014, 03:08 PM   #11
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37 minutes! No, my attention span is too short. Can someone condense it to 3.7 minutes? :-)
10-06-2014, 05:58 PM   #12
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QuoteOriginally posted by tabl10s Quote

ROFL! Waste of time! I stopped when he mentioned that different formats have different ISO calibrations!!! ROFL!!! What an idiot!

The same film emulsion is available in different formats. End of story.
10-06-2014, 06:33 PM   #13
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QuoteOriginally posted by MarkJerling Quote
37 minutes! No, my attention span is too short. Can someone condense it to 3.7 minutes? :-)
Another Full Frame promoting idiot, who also promos his own book, makes a fool of himself trying to redefine the universe to conform to his Full Frame ideology, and while doing so rewriting the ISO film standard to support his ideology. Unfortunately he neglected to inform the International Standards Organization he was doing so. He also believes Aperture is defined in part by DoF even though he has the formula on the board in front of him that actually explains what Aperture is, disproving his point. I think he hoped we wouldn't notice. He actually ignores the formula he uses while making a case for Aperture being defined by DoF. Amazingly, normhead doesn't pop out of the shadows to slap him upside the head for being such a tool, (I was on vacation that day) which is pretty much what he deserves for this 37 minute piece of trash.

It is not a total waste, what he explains he explains well. Unfortunately, when he's doing a snow job he also does that well, so what are you going to do? It's like showing kids an adult movie. You have to have someone sitting there saying "this part is really good", "this part is really bad." If I were him, I'd be ashamed of myself. He clearly has no shame about such blatant, manipulation. Does that make him a psychopath? Or a sociopath? I'm sure it makes him some kind of ____path.Someone with knowledge of the dark sciences give me a heads-up here.

---------- Post added 10-06-14 at 09:50 PM ----------

QuoteOriginally posted by normhead Quote
The current International Standard for measuring the speed of color negative film is ISO 5800:2001[17] (first published in 1979, revised in November 1987) from the International Organization for Standardization (ISO). Related standards ISO 6:1993[15] (first published in 1974) and ISO 2240:2003[16] (first published in July 1982, revised in September 1994, and corrected in October 2003) define scales for speeds of black-and-white negative film and color reversal film, respectively.

The determination of ISO speeds with digital still-cameras is described in ISO 12232:2006 (first published in August 1998, revised in April 2006, and corrected in October 2006).
No where us he total amount of light collected mentioned in the ISO standard. That is simply not in the definition of ISO. Nor should it be. Doing so would defeat the original a current purpose of ISO.

QuoteQuote:
Aperture area[edit]
The amount of light captured by a lens is proportional to the area of the aperture, equal to:

\mathrm{Area} = \pi \left({D \over 2}\right)^2 = \pi \left({f \over 2N}\right)^2
Where the two equivalent forms are related via the f-number N = f / D, with focal length f and aperture diameter D.

The focal length value is not required when comparing two lenses of the same focal length; a value of 1 can be used instead, and the other factors can be dropped as well, leaving area proportion to the reciprocal square of the f-number N.

If two cameras of different format sizes and focal lengths have the same angle of view, and the same aperture area, they gather the same amount of light from the scene. In that case, the relative focal-plane illuminance, however, would depend only on the f-number N, so it is less in the camera with the larger format, longer focal length, and higher f-number. This assumes both lenses have identical transmissivity.


There is no mention of DoF in the definition of Aperture.... the man is delusional.

Last edited by normhead; 10-07-2014 at 05:03 AM.
10-07-2014, 03:08 AM   #14
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It's all information we all know, or at least, information we all should know. The only thing missing from this being a full-scale FF promo video is the wide angle advantage.
10-07-2014, 12:29 PM   #15
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QuoteOriginally posted by normhead Quote
Another Full Frame promoting idiot, who also promos his own book, makes a fool of himself trying to redefine the universe to conform to his Full Frame ideology, and while doing so rewriting the ISO film standard to support his ideology. Unfortunately he neglected to inform the International Standards Organization he was doing so. He also believes Aperture is defined in part by DoF even though he has the formula on the board in front of him that actually explains what Aperture is, disproving his point. I think he hoped we wouldn't notice. He actually ignores the formula he uses while making a case for Aperture being defined by DoF. Amazingly, normhead doesn't pop out of the shadows to slap him upside the head for being such a tool, (I was on vacation that day) which is pretty much what he deserves for this 37 minute piece of trash.

It is not a total waste, what he explains he explains well. Unfortunately, when he's doing a snow job he also does that well, so what are you going to do? It's like showing kids an adult movie. You have to have someone sitting there saying "this part is really good", "this part is really bad." If I were him, I'd be ashamed of myself. He clearly has no shame about such blatant, manipulation. Does that make him a psychopath? Or a sociopath? I'm sure it makes him some kind of ____path.Someone with knowledge of the dark sciences give me a heads-up here.

---------- Post added 10-06-14 at 09:50 PM ----------



No where us he total amount of light collected mentioned in the ISO standard. That is simply not in the definition of ISO. Nor should it be. Doing so would defeat the original a current purpose of ISO.



There is no mention of DoF in the definition of Aperture.... the man is delusional.
Thanks Norm!
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