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Professionals shooting MFT
#11
First, Wim, it was not my intention to attack you. Sorry for the "apparently tonemapping is something you know only by rumors?" and for not regarding what you wrote in that post, I just remembered you saying in another thread 5...6 f-stops are enough dynamic range for you. Obviously I got that wrong, if so - my bad.

 

Btw. film had more than 10 f-stops DR, depending on development and exposure. You don't need to believe me, it's just what I read at Bruce Barnbaum's "The Art of pohotgraphy - An Approach to personal expression". I like his work a lot. He talks about 18 zones, not only 10, but on the other hand he doesn't use a densitometer - so, one can ask how big his logD really was. No matter what, his results are convincing. And even if we're limited today with paper, screens or beamers: Not long ago a screen with full Adobe RGB was nearly impossible to make. Now we're already talking about 8k screens with lots of color depth. I learnt that sometimes the best moments to look at a picture happen a while later.

#12
Most film has DR much lower than 10 stops.

Slide film, loved for its colours and punchy nature, has very unforgiving, low DR, 5 to 6 stops.

Colour negative film ranges from more punchy and contrasty types (the types most used) 7 stops to lower contrast maybe past 10 stops.

Black and white negative film ranges from high contrast to very low contrast, upto 12 stops. Most photographers never used the very low contrast types, they were for specialized jobs.

 

Some confuse the DR one can achieve with the forgiving nature of some film which allows one to under expose (by accident) and still develop the images and get the same 5-6 stops of DR.

 

High DR is either very low contrast, or not visible to us (our eyes at any one time see about 6.5 stops DR), or tone mapped to something unrealistic. One can print very low contrast, and one can print tone mapped unrealistic stuff. 

 

A high DR of 12 stops means saying what we see as white is a grey and white is further up the range, and saying what we see as black is a grey and black is further down the range. That is why high DR is low contrast.

 

Screens have been getting more and more contrasty, not really getting a higher DR for our eyes.

#13
Quote:First, Wim, it was not my intention to attack you. Sorry for the "apparently tonemapping is something you know only by rumors?" and for not regarding what you wrote in that post, I just remembered you saying in another thread 5...6 f-stops are enough dynamic range for you. Obviously I got that wrong, if so - my bad.

 

Btw. film had more than 10 f-stops DR, depending on development and exposure. You don't need to believe me, it's just what I read at Bruce Barnbaum's "The Art of pohotgraphy - An Approach to personal expression". I like his work a lot. He talks about 18 zones, not only 10, but on the other hand he doesn't use a densitometer - so, one can ask how big his logD really was. No matter what, his results are convincing. And even if we're limited today with paper, screens or beamers: Not long ago a screen with full Adobe RGB was nearly impossible to make. Now we're already talking about 8k screens with lots of color depth. I learnt that sometimes the best moments to look at a picture happen a while later.
 

Thank you, JoJu, for the clarification and for saying sorry.

 

FYI, there is a difference in the number of zones, and actual DR. What we do with tone mapping, and teh Zone System, is effectively mapping the DR of one medium to a DR on teh other,which genrally are different. This means changing the gamma, either in a linear way, which in teh Zone System is done mostly by exposure and development of tfilm, and with tone mapping by using an automated option, or partially, like with dodging and burning, or manually tone mapping.

 

As to the 18 zones Barnbaum is talking about, I think that what he meant is that he had 18 zones avaialble with which he could play in thsi regard. 18 stops is about the range of a very brightly lit landscape, from the brightest spots to the darkest shadows. Lookign at what you cna do with film, I guess 18 zones is about right from a tone mapping POV, but you'd have to compress these zones by gamma adjustment before processing the negatives already. This likely means overexposing by approximately 3 f-stops for B&W film and underdeveloping quite a bit. I wouldn't think the results would be extremely pretty, rather low in contrast, based on my own experience, but it can be done I guess.

 

I still have the printed Kodak film profiles and grey wedges somewhere back from the days when I did this type of stuff with film, but I haven't looked at it in years now - no more need Smile.

 

The 5-6 stops of DR I was talking about, is the DR of prints on paper. This is why printers have profiles, in order to make photographs look better, generally speaking. Effectively they also do tone mapping, based on the DR it receives, in combination with the colours it actually can print. From that POV life has become a lot easier Smile. Of course, goor photoprinters allow you to upload printer profiles, but then, most decent image processing software allows you to create printer and paper profiles as well.

 

Technology does advance indeed. I find it a lot easier to make my prints look like they did back in my darkroom days, although I find that because of all the additional fine tuning one can more easily do, I spend about as much time processing my own photographs as i used to do back then Smile.

 

Kind regards, Wim
Gear: Canon EOS R with 3 primes and 1 zoom, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, extension tubes, an accessory plague, and an Olympus OM-D 1 Mk II and Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ...
#14
Quote:Most film has DR much lower than 10 stops.

Slide film, loved for its colours and punchy nature, has very unforgiving, low DR, 5 to 6 stops.

Colour negative film ranges from more punchy and contrasty types (the types most used) 7 stops to lower contrast maybe past 10 stops.

Black and white negative film ranges from high contrast to very low contrast, upto 12 stops. Most photographers never used the very low contrast types, they were for specialized jobs.

 

Some confuse the DR one can achieve with the forgiving nature of some film which allows one to under expose (by accident) and still develop the images and get the same 5-6 stops of DR.

 

High DR is either very low contrast, or not visible to us (our eyes at any one time see about 6.5 stops DR), or tone mapped to something unrealistic. One can print very low contrast, and one can print tone mapped unrealistic stuff. 

 

A high DR of 12 stops means saying what we see as white is a grey and white is further up the range, and saying what we see as black is a grey and black is further down the range. That is why high DR is low contrast.

 

Screens have been getting more and more contrasty, not really getting a higher DR for our eyes.
 

Often teh upper and lower few stops were very limited with B&W film, because they resided on the curves of the gamma curve. Effectively you normally had a maximum of 10 stops, based on my own experience. Low contrast is relative; I used Kodak Panatomic-X most of the time, I think rated at 50 ASA, and exposed it dependign on what I wanted to achieve, between 20 and 125 ASA, and developed accordingly. This most people would see as a relatively high contrast film, but worked perfectly for me Smile.

 

I assume that with the 6.5 stops the human eye can see, you mean what the human eye can see in a single instant. Because the human eye (and brain) can adopt very quickly, what we can perceive in a scene is about 17 stops, as far as I am aware based on teh literature I read over the years. This is because the eye and brain can adapt quickly enough that we don't notice the transitions.

 

Kind regards, Wim
Gear: Canon EOS R with 3 primes and 1 zoom, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, extension tubes, an accessory plague, and an Olympus OM-D 1 Mk II and Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ...
#15
We can adapt the brightness coming on with the size of the pupil, which is pretty fast. But bigger changes are done chemically, and can take upto 30 minutes to adjust. We know this adjustment from going from light to dark, where we need a couple of minutes to adjust, or the other way around (coming from for instance a dark cinema into the sunlight).

 

Looking at images on screens or print will always be viewed at the 6.5 stops at one time DR our eyes have.

 

That you could develop the high contrast under exposed film or over exposed film does not mean the film gave high DR results. 

#16
Quote:We can adapt the brightness coming on with the size of the pupil, which is pretty fast. But bigger changes are done chemically, and can take upto 30 minutes to adjust. We know this adjustment from going from light to dark, where we need a couple of minutes to adjust, or the other way around (coming from for instance a dark cinema into the sunlight).

 

Looking at images on screens or print will always be viewed at the 6.5 stops at one time DR our eyes have.

 

That you could develop the high contrast under exposed film or over exposed film does not mean the film gave high DR results. 
 

Thanks for the expansion on chemical adjustment.

 

I didn;t say film gave high DR results; you mentioned 12 stops, I mentioned 10. Whether that si high or low is debatable, it just depends on where you draw the limit.

 

However, what I meant, and maybe didn't say so clearly, is that you could adjust the gamma and therefore DR range of a film by exposing and developing it in a certain way. In a way, that is tone mapping to a degree, plus burning and dodging, in the digital age, although personally I like to do this manually to have absolute control, and get the image to look the way I want it to look, as I pre-visualized it, and remember it.

 

Very much back to analog for me, but then in digital Smile. I have never been a person to develop and/or print exactly as things were recorded, to me there is no fun in that or even use for that, and once I started to work in my own darkroom, and develop and print everything myself, 40+ years ago, I never did anymore, with the exception of a few snaps, which I would not print myself.

 

Kind regards, Wim
Gear: Canon EOS R with 3 primes and 1 zoom, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, extension tubes, an accessory plague, and an Olympus OM-D 1 Mk II and Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ...
#17
Btw, I suggest this book to everyone, Post Exposure: Advanced Techniques for the Photographer by Ctein. Originally published in 1997, it still contains a ton of very useful information that you can benefit from in digital photography applications and online discussions. He has the entire book online at his website but it says NOT to redistribute the file, so I'm not going to.

 

 

To have some quotes from the first chapter:

 

 

Quote: 

I’ll spare you the math, which is beyond the scope of this book (it involves Fourier transforms, if you want to work it out for yourself ). The difference between a sharp edge and a fuzzy one (a square wave and a sine wave) corresponds to a difference in spatial detail three times finer than the line spacing. In other words, the resolution difference between 10 lp/mm of sharp edges and fuzzy ones is way down around 30 lp/mm. When we notice a difference between those blurry and sharp 10 lp/mm lines, we are responding to detail at 30 lp/mm, even though we can’t directly see it. That’s why materials such as dye transfer and Ektaflex, which display about 20 lp/mm, look fuzzier than chromogenic prints with over 60 lp/ mm. In a side-by-side comparison, you won’t see any more fine detail in a chromogenic print, but you will perceive the detail you can see as sharper
 

Quote: 

Our eyes distinguish a surprisingly small number of tonal steps—fewer than many films and digital sensors can. We don’t notice this because our perceptual systems work to produce an illusion of continuity. We aren’t aware of the steps in our gray response any more than we notice the “blind spot” in our retinas under normal circumstances.
 

Quote: 

“Perfect” tonality for the average viewer requires only about 650 gray steps. You can always put more squares into the tonal scale. For example, you can put that 1.01 lambert square back between the 1.00 and 1.02 squares, but you won’t be able to see it as a distinct square; it will blend perfectly into the squares on either side. No matter what you do to the gray scale, the average human will never see more than 650 squares. Visual artists frequently have better eyes than the average person, but the number of steps is still well under 1000.
#18
Thank you, obican!

 

Here is the link to Ctein's page, you're allowed to link to that one as well:

 

http://ctein.com/booksmpl.htm

 

Kind regards, WIm

Gear: Canon EOS R with 3 primes and 1 zoom, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, extension tubes, an accessory plague, and an Olympus OM-D 1 Mk II and Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ...
#19
Quote:Thanks for the expansion on chemical adjustment.

 

I didn;t say film gave high DR results; you mentioned 12 stops, I mentioned 10. Whether that si high or low is debatable, it just depends on where you draw the limit.

 

However, what I meant, and maybe didn't say so clearly, is that you could adjust the gamma and therefore DR range of a film by exposing and developing it in a certain way. In a way, that is tone mapping to a degree, plus burning and dodging, in the digital age, although personally I like to do this manually to have absolute control, and get the image to look the way I want it to look, as I pre-visualized it, and remember it.

 

Very much back to analog for me, but then in digital Smile. I have never been a person to develop and/or print exactly as things were recorded, to me there is no fun in that or even use for that, and once I started to work in my own darkroom, and develop and print everything myself, 40+ years ago, I never did anymore, with the exception of a few snaps, which I would not print myself.

 

Kind regards, Wim
It more like just adjusting EV in the RAW processor, ending up with a normal DR (lets say 7 stops, normal contrast, or 5 stops, high contrast) in the end product.

So yes, the film itself has a "high DR" for exposure, but the developed film does not. It is like a window of limited DR gets moved along the wider DR latitude of the undeveloped film, and where that window stops depends on the development time of the film.

#20
Quote:It more like just adjusting EV in the RAW processor, ending up with a normal DR (lets say 7 stops, normal contrast, or 5 stops, high contrast) in the end product.

So yes, the film itself has a "high DR" for exposure, but the developed film does not. It is like a window of limited DR gets moved along the wider DR latitude of the undeveloped film, and where that window stops depends on the development time of the film.
 

I'd have to check. From what I remember it is really up to 10 stops or even slightly more, but I'll need to find the stuff I have on this at home, which currently is difficult to find due to the basement flooding we experienced last year - everything is stacked in a way making it unaccessible, and I expect that I will only have access to thsi stuff again by the end of March or thereabouts. I have some Kodak pro documentation on this stuff somewhere.

 

The last few stops, at the end and at the top, really only have a shortened height on gamma curves, but they are there. If you are talking about the straight part of the gamma curve, you are correct, that is about 7 stops, maybe 8, but even Ansel Adams worked with a DR of around 10 stops (Zones 0 to 9).

 

Kind regards, Wim
Gear: Canon EOS R with 3 primes and 1 zoom, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, extension tubes, an accessory plague, and an Olympus OM-D 1 Mk II and Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ...
  


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