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05-06-2015, 03:40 PM   #91
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What is a sensor? What is a pixel, from the point of view of his electronical functionality? How it works? What is thermal noise? Why high ISO is noisier?

05-06-2015, 04:27 PM   #92
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QuoteOriginally posted by FantasticMrFox Quote
Considering that recent Nikon and Sony sensors are virtually ISO-less there is not much of a difference between shooting at high ISOs and pushing shadows - both work on the same principle. The latter would just mean selectively increasing the ISO in the shadows instead of across the whole frame, naturally that won't give great results. There's just a limit to how much a camera can artificially increase a signal from an area that didn't yield a lot of information/light in the first place.
Hence the ETTR method. It is THE best way to get the least amount of noise out of a file.
05-07-2015, 02:19 AM   #93
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QuoteOriginally posted by Flugelbinder Quote
Flugelbinder's Avatar Join Date: Nov 2014 Location: Toronto - missing the ocean Posts: 430 | Likes: 27 QuoteOriginally posted by FantasticMrFox Quote Considering that recent Nikon and Sony sensors are virtually ISO-less there is not much of a difference between shooting at high ISOs and pushing shadows - both work on the same principle. The latter would just mean selectively increasing the ISO in the shadows instead of across the whole frame, naturally that won't give great results. There's just a limit to how much a camera can artificially increase a signal from an area that didn't yield a lot of information/light in the first place. Hence the ETTR method. It is THE best way to get the least amount of noise out of a file.
ETTR or ITTR or HAMMSTR, whatever we call it, is again only part of things to consider. Yes it has strong sides, so it have limitations of it's own.
Pretty good explanation - /little physics behind/ is here: https://luminous-landscape.com/optimizing-exposure/ would say, must read for anyone.

A bit of word rolling, to help understand some concepts from ETTR and its components better here: Are you Shooting HAMSTTR? - ETTR - Expose to the right -- Canon EOS Digital Cameras in photography-on-the.net forums

But again, Source light>(lens+setting -light>Sensor (sensor overall area, pixel size, type, material, micro-lens above it, sensitivity, sensor full, sensor EQ and other parameters )>analog signal- analog signal read, signal-noise ratio, analog signal amplification and it's parameters, analog digital conversion>filtering> all kinds of post-processing.
ETTR is not magic tool to get over differences and limitations in whole chain!
It's just technique to acquire certain types of images in some situations better.

Now, if some one wants truly to understand, why "size matter", when size matter, why all holes "do not feel same" when you put "things" into them, why DR is not only thing what even nowadays matters - what depends on ISO speed or how and when DR matters - i just point out some articles -easily found in internet.

First some "obscure" numbers here: Sensorgen - digital camera sensor data
A lot of numbers. After short while, one should be able to see some patterns in cameras of their taste or interest.
Look at cameras you know, look samples you have seen from ones or others, and THINK- do or how do numbers here relate to picture you see out from these cameras you are interested?

Just enormous work is done by Roger N. Clark, on next links from he's home page.
Some pages that one should read and understand for talking about sensors and camera performance. This is not easy reading, not for everyone understanding, needs and taste. Read only if you are interested.

Clarkvision: Digital Camera Review and Sensor Performance Summary
Not too latest data in some tables maybe, and many Sony's are not there, but limitations in the physics remain, and it's good to know them, before bashing more on sensors MP-s alone.
After reading this one, look back to sensorgen website data, how does this table look now? Do you see why 645Z is noisy? Do you see why old canon 5D and 6 D excels? Do you see, how average in those areas are pentax ones? Do you see how is that K3 sensor is not that good as K5 in some areas?
Also one can see quite obvious sensor parameter differences between consumer series in brand cameras. (price level separations).

If you still don't, and your brain is not over-saturated yet, please read this one:
Clarkvision: Digital Camera Review and Sensor Performance Summary with all links behind.

Very well presented data from one who really UNDERSTANDS what he is talking about!
Excellent article. Most of us can see, but here is it written in one place -why we see results out from cameras, what we see.

I have to repeat myself. Please look WHOLE PICTURE, when you make statements - what really matters in one or other camera and do that according your needs. (most people do not need anything from what is provided). But do not focus on limited set of factors!

And last i like to quote Clark's statement:
QuoteQuote:
Image quality is subjective and the bottom line is lighting, composition and subject are more important than the inherent image quality that a camera delivers. I have been studying sensor performance for two reasons: intellectual curiosity and a better camera for astrophotography. In comparing results on this page, do not get too carried away with over-interpreting the results. You would probably do better spending your time out photographing and refining your knowledge on lighting, composition, and subject.
I tend to share that kind of intellectual curiosity too and try to understand what makes cameras really different.
05-07-2015, 02:34 AM   #94
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QuoteOriginally posted by Vihmameister Quote
ETTR or ITTR or HAMMSTR, whatever we call it, is again only part of things to consider. Yes it has strong sides, so it have limitations of it's own.
Pretty good explanation - /little physics behind/ is here: https://luminous-landscape.com/optimizing-exposure/ would say, must read for anyone.

A bit of word rolling, to help understand some concepts from ETTR and its components better here: Are you Shooting HAMSTTR? - ETTR - Expose to the right -- Canon EOS Digital Cameras in photography-on-the.net forums

But again, Source light>(lens+setting -light>Sensor (sensor overall area, pixel size, type, material, micro-lens above it, sensitivity, sensor full, sensor EQ and other parameters )>analog signal- analog signal read, signal-noise ratio, analog signal amplification and it's parameters, analog digital conversion>filtering> all kinds of post-processing.
ETTR is not magic tool to get over differences and limitations in whole chain!
It's just technique to acquire certain types of images in some situations better.

Now, if some one wants truly to understand, why "size matter", when size matter, why all holes "do not feel same" when you put "things" into them, why DR is not only thing what even nowadays matters - what depends on ISO speed or how and when DR matters - i just point out some articles -easily found in internet.

First some "obscure" numbers here: Sensorgen - digital camera sensor data
A lot of numbers. After short while, one should be able to see some patterns in cameras of their taste or interest.
Look at cameras you know, look samples you have seen from ones or others, and THINK- do or how do numbers here relate to picture you see out from these cameras you are interested?

Just enormous work is done by Roger N. Clark, on next links from he's home page.
Some pages that one should read and understand for talking about sensors and camera performance. This is not easy reading, not for everyone understanding, needs and taste. Read only if you are interested.

Clarkvision: Digital Camera Review and Sensor Performance Summary
Not too latest data in some tables maybe, and many Sony's are not there, but limitations in the physics remain, and it's good to know them, before bashing more on sensors MP-s alone.
After reading this one, look back to sensorgen website data, how does this table look now? Do you see why 645Z is noisy? Do you see why old canon 5D and 6 D excels? Do you see, how average in those areas are pentax ones? Do you see how is that K3 sensor is not that good as K5 in some areas?
Also one can see quite obvious sensor parameter differences between consumer series in brand cameras. (price level separations).

If you still don't, and your brain is not over-saturated yet, please read this one:
Clarkvision: Digital Camera Review and Sensor Performance Summary with all links behind.

Very well presented data from one who really UNDERSTANDS what he is talking about!
Excellent article. Most of us can see, but here is it written in one place -why we see results out from cameras, what we see.

I have to repeat myself. Please look WHOLE PICTURE, when you make statements - what really matters in one or other camera and do that according your needs. (most people do not need anything from what is provided). But do not focus on limited set of factors!

And last i like to quote Clark's statement:
I tend to share that kind of intellectual curiosity too and try to understand what makes cameras really different.
I am not sure that I follow your question why the 645z is noisy. It is less noisy than about any other camera I've seen. It doesn't have the best auto focus system, but its high iso ability is significantly better than the other cameras you listed. Newer tech does make a difference and the 5D does not match up well against current APS-C sensors, either.

05-07-2015, 04:39 AM   #95
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QuoteOriginally posted by Rondec Quote
I am not sure that I follow your question why the 645z is noisy. It is less noisy than about any other camera I've seen. It doesn't have the best auto focus system, but its high iso ability is significantly better than the other cameras you listed. Newer tech does make a difference and the 5D does not match up well against current APS-C sensors, either.
Not only that, but the Nikon keeps getting omitted. A quick look at DPreview's Studio Comparison and it's obvious what's the best/cleanest sensor at high ISO...
05-08-2015, 12:07 AM   #96
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QuoteOriginally posted by Rondec Quote
I am not sure that I follow your question why the 645z is noisy. It is less noisy than about any other camera I've seen. It doesn't have the best auto focus system, but its high iso ability is significantly better than the other cameras you listed. Newer tech does make a difference and the 5D does not match up well against current APS-C sensors, either.
No you didn't, but no problem. About 645z -it depends on what iso you look at and what camera you compare with. Same count.s about Canon. On some areas it does not catch up, but overall performance is still very good.

QuoteOriginally posted by Flugelbinder Quote
Not only that, but the Nikon keeps getting omitted. A quick look at DPreview's Studio Comparison and it's obvious what's the best/cleanest sensor at high ISO...
Omited in table of theoretical measures, some of what made 2008-2009? Interesting that D750 isn't there.
But just some 2 pages back i told what are best sensors on current lineup from major brands, and i named 3 Nikons (D810, D610, D750) Then we had to discuss sony A7s. And resume was - canon's answer to nikon lag's some 1,5-2 years usually. So if you like Nikon now, go for it, you make no mistake. Some people just wait for pentax FF and myself for Canon 6D v2 pricerange and functionality wise.
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