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07-13-2015, 11:29 AM   #46
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QuoteOriginally posted by normhead Quote
SO when does this theoretical noise difference kick in?
Is it not implied (understood) that the FF noise advantage is actually High ISO noise advantage?

07-13-2015, 11:35 AM   #47
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QuoteOriginally posted by dtmateojr Quote
Equivalence has this crazy assumption that you could just bump the ISO indefinitely.
wrong.

there is no equivalence rule that makes that claim.

QuoteOriginally posted by dtmateojr Quote
Compare the same m43 and FF sensors. If the sensor has a native ISO limit of 6400
"One can find on the internet discussions about the "Native ISO" for a camera. There is really no such thing."
Clarkvision: Digital Camera Review and Sensor Performance Summary

QuoteOriginally posted by dtmateojr Quote
Equivalence is wrong, plain and simple.
the only thing wrong here is the same rubbish claims that you keep posting in these equivalence threads
07-13-2015, 12:22 PM - 1 Like   #48
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I have watched this thread evolve over 4 pages of posts now, and have exercised considerable restraint to wait this long to post, but I have decided that it is time to throw a stone into the pond and watch the ripples that radiate outward.

So here goes.


Who really gives a $#!+ about equivalence any way.

Many of the shooters here only shoot one format, APS-C.

So :
-focal length is focal length, I.e. The distance of a simple lens from the focus plain at which parallel light rays entering the lens converge in a point.
-F stop is f stop, the mathematical ratio of aperture to focal length
-DOF is an illusion because it ultimately is the range of distances from subject to lens where a point of light is, by the time it is enlarged to final print, less than 0.01 inch in diameter, but every one prints a differen size so there is no such thing as equivalent DOF


So let's break clean. There is no such thing as equivalent to 35mm focal length, just like there is no equivalent 645 , 6x7, 4x5 or 8x10 focal length for any criteria

There is only focal length and aperture and how they work on a given format. Learn to use the gear available and forget trying to copy what someone else is doing in a different format.

Copying someone else's techniques without thought on your own will get you no where. Understanding hot to get a unique shot with what you own is what makes a photographer stand out. If shallow DOF was the be all and end all of photographic licence, fast MF lenses and MF cameras would own the pro market. Since they do not, obviously in the global scheme of things, it is just not as important as people make it out to be. It is mor a reason of why not APS-C than what you can do with APS-C. As always, it is much easier to give reasons of objection, than give the thought as to how to overcome the perceived limitaitons
07-13-2015, 12:51 PM   #49
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QuoteQuote:
FF has lower noise than smaller sensors, when viewing at equal resolution, or when printing to the same size.
You said it, not me. You quoted a stat that doesn't equalize for DoF. When viewing at the same size and resolution and DOF, FF has no noise advantage, because it has to give up it's one stop of noise advantage, to shoot with a one stop higher ISO and one stop smaller aperture, to equalize DoF IN that case the smaller sensor, is utilizing twice the light on half the sensor size, the light, total light utilized in creating the image is the same, noise should be the same. Look at the examples above, there is no noise advantage to the larger sensor. Did you even look at the examples? How can you keep saying that, in the presence of real world evidence to the contrary?

QuoteQuote:
So let's break clean. There is no such thing as equivalent to 35mm focal length, just like there is no equivalent 645 , 6x7, 4x5 or 8x10 focal length for any criteria
Exactly, stop proclaiming "this format is better than that format," for what ever reason, and go shoot some pictures. If you can't prove your point with a few images, you don't have a point. Quit spouting the photo-blog rhetoric. It's sickening.

If someone wanted to post a couple images, one with FF and one with APS_c and discuss their expeience with those images, that would be totally fascinating. This endless parade of people regurgitating web losers whacked out theories has got to stop. Half these dudes are out of their freakin minds. I don't raed them because it hurts me to have to experience such ignorance. Having people post their hogwash on here just sucks. If you think they're so great, go post on their web site. Leave us alone.


Last edited by normhead; 07-13-2015 at 01:05 PM.
07-13-2015, 12:56 PM   #50
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It is useful to understand equivalence when trying to reproduce someone else's work, or mimic a style. I remember reading Understanding Exposure and wondering why my little p&s at f2.8 didn't give me the shallow DOF shown in his images. His advice to use f16 for a particular landscape image did not translate well to a p&s either, nor does it with APS-C. When I recommend this excellent book, I've tried to warn the person about equivalence. If one is shooting m4/3, increase his aperture settings by two stops, or one stop for APS-C, etc.

The other very common scenario is when someone is evaluating what system to buy into. How does a Sony RX-10 with 8.8-73.3mm f2.8 lens compare to a DSLR with kit lenses? Equivalence can give you a reasonable answer.

---------- Post added 2015-07-13 at 16:34 ----------

QuoteOriginally posted by normhead Quote
APS_c------------------- FF

IS0 100...................ISO 200 - DR and noise are equivalent
1/100s....................1/100s - shutter speed is equivalent
ƒ2.8........................ƒ4 - total light used by the sensor to create the image and DoF are equivalent.

These images are roughly equivalent (ignoring the 1/3 stop) . There is simply no FF advantage. What you gain in DR and noise, you lose to maintain depth of field, should you choose to go that route.
I agree with everything above. You stated equivalent conditions properly (assuming similar levels of sensor technology). Your complaint seems to be that equivalence theory requires that everyone agree FF is superior, which is not part of equivalence theory. IMO, APS-C is the best format for me.
07-13-2015, 01:39 PM   #51
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QuoteOriginally posted by audiobomber Quote
It is useful to understand equivalence when trying to reproduce someone else's work, or mimic a style.

Therefore equivalence must be rejected when trying to avoid reproducing other people's work or mimicking other people's styles.
07-13-2015, 01:45 PM - 1 Like   #52
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Simply put.. take an old piece of 35mm film.
Take a photo.
Take an equivalent piece of film and put black tape around the edges to make the exposed portion of the slide to match a crop sensor size.
Take the same photo.
(Same can be done with your FF DSLR, but the tape might ruin your sensor)


With all other aspects of the camera settings, position, lighting and subject being equal (just as they would between a FF v.s crop body)
Does the resulting DOF change?
Does the resulting ISO change
Does the resulting exposure change?


The change in file size (i.e. sensor size) does not change the physical properties of the light coming through the lens.

07-13-2015, 01:57 PM   #53
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QuoteOriginally posted by kh1234567890 Quote
I love these equivalence threads ...
Lots of one sided conversation...half the people in this thread were boriscleto'd™ long ago.
07-13-2015, 01:59 PM   #54
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Did they have 'equivalence wars' when film users abandoned their 'full frame' cameras for APSc or, like me, did most of us just carry on snapping and adapted to the new format without worrying about equivalence ?
07-13-2015, 02:00 PM   #55
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QuoteOriginally posted by amoringello Quote
With all other aspects of the camera settings, position, lighting and subject being equal (just as they would between a FF v.s crop body)
Does the resulting DOF change?
Does the resulting ISO change
Does the resulting exposure change?
That's because the equivalence magic only happens when you view the picture ...
07-13-2015, 02:09 PM   #56
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QuoteOriginally posted by kh1234567890 Quote
That's because the equivalence magic only happens when you view the picture ...
Exactly But that goes beyond the original question and is not a complete picture. You also need more information on how it is viewed.
Sensor size does not affect how the lens behaves.
07-13-2015, 02:17 PM   #57
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All you need to know about equivalence is, if you can take the picture you want on one camera, you can probably take it one format larger or one format smaller, the odds are 95% in your favour. But honestly, most of us know what to do with the camera we have to get the picture we want. Not because we understand equivalence, but because we've spent a lot of time learning our camera. Does the theory of equivalence mean you don't have to learn your bigger format camera? You can just think APS-c and use equivalence? Not at all, you still have to learn your new camera system.

Equivalence is like a coffee table book. GO through it, read a bit of the text look at the pictures... ( no pictures? Toss it.) Pass it on to your cousin. You don't need to read it twice. Understanding equivalence is less that .005% of photography, but thread after thread on the forum.
07-13-2015, 02:21 PM   #58
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QuoteOriginally posted by normhead Quote
All you need to know about equivalence is, if you can take the picture you want on one camera, you can probably take it one format larger or one format smaller, the odds are 95% in your favour. But honestly, most of us know what to do with the camera we have to get the picture we want. Not because we understand equivalence, but because we've spent a lot of time learning our camera. Does the theory of equivalence mean you don't have to learn your bigger format camera? You can just think APS-c and use equivalence? Not at all, you still have to learn your new camera system.

Equivalence is like a coffee table book. GO through it, read a bit of the text look at the pictures... ( no pictures? Toss it.) Pass it on to your cousin. You don't need to read it twice. Understanding equivalence is less that .005% of photography, but thread after thread on the forum.
Sounds like a wise conclusion.
07-13-2015, 02:26 PM   #59
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QuoteOriginally posted by starbase218 Quote
Why not? The only difference between bumping ISO in the native range and bumping it further is where the bumping takes place: in the former case the analog signal gets amplified before conversion to digital. In the latter case, the digital signal gets "amplified" (technically, the signal is not amplified, because it's a series of ones and zeroes, but the digital signal is changed so that the outcoming ones and zeroes represent a bumped signal). So why does it matter where the bumping takes place?

Bumping outside of the native range does introduce a little more noise I think, because the D/A conversion itself will also introduce a bit of extra noise, which otherwise would not get amplified.

Anyway, we are dealing with a very specific corner case here, in which one system does not get bumped into non-native ISO and the other does. Surely you must see that.



So you are saying that, in some cases, you cannot bump the ISO on a fullframe sensor? Really?



Speak for yourself. If anything, I'm arriving at the conclusion that this is not plain and simple at all.

I'm also a little puzzled how it is possible that the D7000 and D800 use the same sensor, yet the one in the D800 is 2.25 times as big.



---------- Post added 07-13-2015 at 07:30 PM ----------



What's also interesting to see is that the difference is about 4dB. 3dB means a signal twice as strong. The sensor area is 2.25 times as big on fullframe, so if it were equivalent, we'd expect a difference of about 3.5dB. Reality is not far off, at least in this case.

In film photography you can't even bump the ISO. The "equivalent" method is called push processing. It means that if you shot a 135 film and then severely underexpose a 8x10 sheet to get an equivalent image there is no way you can push that 8x10 film to your target. Ever tried pushing transparency film by 5 stops?! That is practically the entire usable DR of Velvia!!!

If it doesn't work with film, the theory is wrong. Plain and simple.

---------- Post added 07-14-15 at 07:45 ----------

Here's another example. If a m43 sensor has captured enough number of photons to go 4 times above the noise floor, an equivalent FF exposure would mean that the signal will only be as strong as the noise. Bump the ISO on the FF and what you'll get would just be noise.
07-13-2015, 03:50 PM   #60
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QuoteOriginally posted by dtmateojr Quote
In film photography you can't even bump the ISO. The "equivalent" method is called push processing. It means that if you shot a 135 film and then severely underexpose a 8x10 sheet to get an equivalent image there is no way you can push that 8x10 film to your target. Ever tried pushing transparency film by 5 stops?! That is practically the entire usable DR of Velvia!!!

If it doesn't work with film, the theory is wrong. Plain and simple.
You will forgive me for not subscribing to absolutes like that? The statement doesn't mean much to me anyway, since I never shot film.

QuoteOriginally posted by dtmateojr Quote
Here's another example. If a m43 sensor has captured enough number of photons to go 4 times above the noise floor, an equivalent FF exposure would mean that the signal will only be as strong as the noise. Bump the ISO on the FF and what you'll get would just be noise.
Not necessarily. If the FF has the same amount of pixels, each pixel would have less noise to begin with. So the noise floor on that sensor is lower as well. Maybe your theory holds true if the pixels are the same size. But even then the random nature of noise would make for a finer pattern.
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